Julian Chua

The iPad Cooling Case Is Now Live At Wombat Ware

Posted on September 6, 2021 by Julian Chua

This is a bit of a delayed update over here. For those of you who have been following us or following the development of the iPad Cooling Case, I am happy to announce that you can now jump over to Wombat Ware (www.getwombatware.com) to see the latest development and updates there.

What is available now?

I have first launched the iPad Cooling Case product for the iPad Mini 5 (or 5th gen). The reason for just releasing a Cooling Case for one model is simply because of limited resources (for now) and the reason I picked the iPad Mini 5 is that that’s the more popular model used by pilots and drone pilots. Or at least the majority of those that contacted me were using the iPad Mini 5.

Will there be Cooling Cases for other iPad models?

The short answer is ‘Yes’. I am now working on a case for one of the 9.7″ models (iPad Air, iPad 5/6) and if nothing goes too wrong, that should be available in the next few months. I will also keep working on other models based on the number of requests – i.e. if there is a huge request for a specific iPad model or tablet model, that will be next on the list.

I am also developing custom accessories that work with the iPad Cooling Case. One recent example is an adapter that allows the iPad Cooling Case to be mounted on a DJI MavMount Adapter. We are calling it the Wombat Ware MavMount Adapter or WWMM adapter.

Since the motivation for bringing the iPad Cooling Case to market is to provide a useful solution, making custom accessories that work with the iPad Cooling Case makes total sense. If you think you also need a custom attachment or accessory or even an alternate solution, please feel free to reach out to us here (ReEngineering Labs Contact Page Link) or here (Wombat Ware Contact Page Link).

Updates On The iPad Cooling Case Development

Posted on November 13, 2020 by Julian Chua

Here are some updates on the development of the iPad Cooling Case that I have been working on and off since 4-5 years back and have focused on more in 2020. There have been a few challenges (some related to Covid, some not) but there have also been some good conversations and work that have helped move this development forward. So I am now closer to finishing and launching.

User Testing & Feedback

When I did a reboot of the this project a couple of years back, the main targeted users were pilots. So this year, I have had some meaningful conversations with different users ranging from private to commercial pilots and military. A couple of them had the chance to use the beta test units. It was evident some changes were necessary.

More Design Changes

There are a few design related things that I have worked on and they are based on those conversations and feedback including:

The need for protection for the iPad, particularly on the corners
The on/off switch for the cooling/electronics can’t be too small
Battery life of the unit could be longer
Easier access of charging port
The need to work with existing mounting solutions

Thinking About Production

As I plan the next steps including going into production, I am looking into small batch production and having the option and ability to make slight modifications should the need arise. So I will be exploring additive manufacturing and potentially getting it done locally. Yes, the cost of manufacturing per unit will be higher but there will be more agility and potentially less wastage of resources at the start. There is another benefit of additive manufacturing: although my focus is currently on the iPad mini 4 & 5, additive manufacturing gives me the ability to customise solutions for different iPad models.

Accessories That Will Work With The Cooling Case

As mentioned above, one important feedback I have received is that pilots want the iPad Cooling Case to work with existing mounting solutions. The most common mounting options are either kneeboards or suction mounts. For suction mounts, there are 2 popular solutions and they are RAM mounts and MyGoFlight mounts. RAM mounts use the AMPS pattern which is a standard 4 hole pattern. MyGoFlight mounts also sell adapters that can work with the AMPS pattern mount. So the iPad Cooling Case will incorporate the AMPS pattern so that it could work with those solutions.

I have also tested the iPad Cooling Case with the RAMS X-Grip suction mount and I think that works well. The optional tether provides additional securing of the iPad with the Cooling Case.

In terms of kneeboard mounting, besides ones that will work with the AMPS pattern, there are also kneeboard solutions that have universal securing means. One example that I have tested is the MyClip Multi strap. From my initial testing using one of my beta units, it works pretty well and can be swapped between landscape or portrait mode.

Next Steps

I am also trying to find out what other accessories pilots need to have while using their iPad ( and Cooling Case). If you would like to share with me what accessories you use with your iPad, please leave a comment below or send me a message here – contact page. I would really appreciate that and it will help me make the solution even more usable for more people.

Lastly, if you would like to be informed when the product is launched (hopefully early 2021), please leave me a message (contact page) and I will be in touch. Thank you!

The iPad Cooling Case Reboot

Posted on October 1, 2018 by Julian Chua

How It All Started

The iPad overheating was first brought to my attention back in 2013 when a sports scientist approached me and needed a solution to cool down his iPad when he used it in the sun. I designed a proof of concept and a prototype and showed that an iPad case with fans and cooling channels was likely the simplest and most effective solution.

Read more about that design and testing here: Designing An iPad Cooling Case.

The original case with cooling channels

[If you are just interested in finding out how to get an iPad cooling case for beta testing or want to be notified when it is available, feel free to skip to the last part: here]

Putting it aside

At that time, I thought that an iPad cooling case was probably a product only a handful of people in the world would want. Few people (in my opinion) would use their iPad to the extent of overheating and even if it did they might give it a rest or move it to the shade assuming it was in the sun in the first place. Never the less, I created a survey to seek out what other possible applications it might have and tried to share it around. Unfortunately, I did not get any response for the next 5-6 months. Convinced then that the solution wasn’t needed, I decided to just let it rest.

Reboot 0.5

Fast forward to 2016, I received a couple of emails/comments from people who read the above blog post. Someone commented that they need it too for sports. The other 2 were from pilots who used iPads when flying. I had an email exchange with one of the pilots and found that the iPad overheating (and shutting down) was a big enough problem for him as it kept him from using it for navigation. I spent some time looking at redesigning the cooling case and possibly making a small batch of it. But with other life demands on my end, I had to put it on hold.

Reboot 2

Roll forward again to 2018, Survey Monkey, where I created the survey, sent me a notification reminding me that I should log in again to their website or else they will delete my account. As I logged in, lo and behold, the iPad cooling case survey had continued to live (even with my neglect) and it had collected a good number of responses since March 2014. Over 70% of those responses would like to have a cooling solution for their iPads! (I am a bit curious why I didn’t get a notification from Survey Monkey about all those responses.)

The Survey Monkey Notification

Another check on WordPress stats tells me that the story/blog post I wrote about designing the iPad cooling case is the top four (most viewed) posts in the last 3-4 years. That’s quite surprising. I was a bit bummed that I let all that slip past me but on a positive note I take those as signs telling me enough people wanted a cooling solution.

The Top 4 posts excluding the home pages.

So here we are, back at the drawing board – ironing out the designs (mechanical and electronics), figuring out the bill of materials (how much it will cost), planning out the path to production, organising testing and sorting out any other issues.

What has been done so far in the last couple of months:

rebuilt the temperature sensor circuit and cooling mechanism
redesigned the case so that it is slimmer
relooked at the cooling case design and how it could be more universal

What else needs to be done:

build the electronics on custom PCBs and test them
build a small quantity for beta testing with users
finalising designs
get electrical testing done to make sure it’s all safe.

Testing

Currently, I am organising testing with people who use their iPads during flying. For logistical reasons, my preference is to get people who are local in Australia to do the beta testing and get their feedback. Also, for a start, I am working on cases that fit the iPad mini 4 and the newer 9.7″ models (iPad Pro 9.7″ and iPad Air 2).

If you are keen to be involved in testing an iPad cooling case, please contact me here (link), select “iPad cooling case” and let me know:

which iPad model you need a case for (preferably it would be one of those mentioned above but if not I will do my best to accommodate)
how regularly you need to use it.
any additional information you feel is required

Also, if you would like to pre-order or be notified when the iPad cooling case is available on the market, please fill up the same contact form.

With that thanks for reading and stay cool. 🙂

Developing IMU Sensors For Capturing Motion In Sports

Posted on August 4, 2018 by Julian Chua

IMU sensors are pretty useful because when strapped to the right location and given the right context they can provide very insightful information about an athlete’s (or anyone’s) movements. In this post, we are going to look at a couple of options in the market that allows us to skip the hardware development and jump right into the application development. Feel free to skip to the different sections that interest you:

[ Intro To IMUs – mbientlabs – Notch Sensor – Notch Mocap Test – Custom Sensors]

Intro To IMUs

In case this is the first time you are hearing about IMU, here’s a brief intro. IMU stands for Inertial Measurement Unit; it is an electronic device that typically has accelerometers, gyroscopes and magnetometers, and it measures its own acceleration, angular rate (or spin rate) and surrounding magnetic field. IMUs are not only used in sports, in fact, it is used in many consumer electronic devices. Our smartphones for one has IMUs for detecting the orientation of the phone and changing the display to portrait or landscape. The IMUs also allows for functions such as undoing texting errors, a spirit level and motion sensor games. If a user carries the phone with them in their pockets most of their waking hours, it can act as a pedometer counting steps and detect when the user is sedentary. For runners who use running apps to track their runs, IMUs enable some apps to track indoor runs and cadence. Sports Engineering Researchers have used smartphones for tracking wheelchair rugby activities and classifying different sporting activities.

As great as the smartphones are with inbuilt IMU, GPS and processing power to give us real-time analysis, we don’t really want to strap an expensive smartphone onto a football player’s calf to monitor their kicking or tape an iPhone to a tennis racket to measure swing metrics. That’s why companies like Qlipp has developed sensors for tennis or Zepp which has sensors for a number of bat-and-ball or swing type sports. Then there are sensors for rowing, running, surfing, mountain biking and more. There are also different sports equipment that has in-built IMU sensors. Like smart balls (basketball, football, cricket ball etc), smart shoes, smart helmets, smart rackets etc, it could go on and on.

But sometimes we might still not find a sensor product on the market that is right for our sports or health application. So we explore the option of developing something on our own. Fortunately, we don’t necessarily have to start from scratch* because these days there are generic IMU sensor platforms that are designed and built for people who want to develop a sensor for a custom application. They often have the standard 9-DOF (degree of freedom) sensor setup and come with software SDK that allows developers to build their own applications for processing and analysing the data. Let’s look at a couple of options below.

[*when I say scratch, I mean getting sensor boards from SparkFun, Adafruit, Seeedstudio, Tindie etc]

mbientlab

mbientlab successfully launched their first Bluetooth IMU sensor on Kickstarter. They pitched it as a development and production platform for wearables with simple API for iOS and Android. There was some simple soldering required when people bought the first product. I didn’t get one from that campaign but I did get a later updated version which they called MetawearRG. What impressed me when I first got it was the size of it – it’s small and compact and I could use it to build/redesign a smart basketball prototype for a client. Then when I started testing it, I found that their API was really easy to use and I could use their sample iOS app to build a custom app for testing within a (reasonably) short time.

: Smart Basketball Prototype and Watch app for tracking optimal shots

Since then, they have made many other versions of sensors with:

slightly different sensor configurations,
options of coin cell or rechargeable lithium battery,
accessories such as cases, clips or wristbands,
sensor fusion firmware,
cloud services, and
hubs to manage multiple sensors.

: Metawear RG with custom 3d printed sleeve/case (L) and Metamotion (R)

I haven’t had the chance to try everything but I have to say, I have had a good experience using their Metawear and Metamotion sensors to build various proof of concepts and I am still using them for a number of projects. The sensor data can be streamed to your smartphone or logged on the device. In terms of API support, on top of iOS and Android, they have added Python, C, C# and Javascript, so developers can build stuff on various platforms.

Sample/Template Metawear iOS app for testing

Looking at their new website revamp and some recent emails they sent out about new platform developments, they seem to be putting more focus into the allied health space, in particular, measuring range-of-motion (ROM). They are currently beta testing an app called the MetaClinic and it looks like they are using skeleton-tracking the likes of motion capture systems which would probably mean we need to use multiple sensors. That should be interesting.

MetaClinic App by mbientlab

Notch Sensors

Notch also launched on kickstarter, in fact slightly earlier than mbientlabs’ campaign. They had an interesting concept of integrating individual IMUs into custom designed clothing using pockets in discreet locations. Unfortunately, they weren’t successful at that instance. Their initial use case probably wasn’t strong enough. So I guess the founders went back to the drawing board, revamped it all and went with the “motion capture” approach for developers.

Notch sensor with elastic band and clip

With the new design, the shape of the IMU sensor is essentially the same but they have ditched the micro-usb in each IMU for contact pins and made it water-resistant (IP67). They also designed elastic bands of varying lengths with a sensor clip and a user can secure each sensor up to 15 different locations on their body including head, chest, upper arms, wrists, hands, waist, thighs, ankles and feet. So instead of selling individual IMUs, they sell a kit of 6 IMUs with a set of elastic bands, and if a user wants to do a full (body) setup, they will need 3 kits.

The Pioneer Kit: 6 IMUs with charging case and elastic bands with clips.

A quick test and review (for biomechanics)

I had the opportunity to run a short pilot test with one (the pioneer) kit in a biomechanics lab. I used the lower body setup which used all 6 IMUs strapped on my chest, waist, thighs and shins/ankles. In terms of setting up, it was pretty straightforward. After following an initial calibration procedure of all the IMUs in the case, I put on the bands and clipped each IMU to the right location according to the different colours as indicated on the app. The only thing is putting on the bands takes a bit of practice and I had to swing around to check that the bands are not too tight and restricting movement. Even though I don’t have muscly quads, I felt that the bands were somewhat tight and needed adjusting after a while.

Setting up the Notch IMUs for lower body measurements

For testing, I did a simple protocol of walking, stopping and doing 3 squats of varying depths. Then I compared my knee angles measured on the notch and the motion capture system. A few quick things that I took out of the knee angle measurements were:

The angle measured by Notch is the exterior angle while the motion capture system looks at the interior angle. So it needs a quick recalculation before comparison.
Assuming the motion capture system is the more accurate measurement, Notch had a larger error as squats went deeper.
But for walking, the knee angles measured were quite close.

It’s wasn’t a very elaborate test but even from this simple outcome, I can safely say it’s probably not the best tool for accurate joint angle measurements. Although for a quick 3D visual feedback on movements, it might work. Here’s the clip of me doing the test described above (feel free to rotate the video to get different perspectives):

Further to that, I could only download angle data. If I wanted the raw sensor (acceleration and gyro) data, I would need to pay for an extended license that is renewed annually.

In terms of custom development support, they used to have support for iOS but they seem to have taken that off now and only have support for Android which I thought is a bummer. I am guessing they have some issues with getting it right on iOS. Hopefully, it is just temporal and they will resolve it soon. For Android developers, it looks like they have pretty good support and even provides a template app. I have to add that there is a fair bit of fine print I need to agree to before I can get access to their SDK. If I read it right, they basically want a licensing fee for using/commercialising their SDK.

Custom Sensors

Both of the above IMU sensors have similar specifications when it comes to measuring acceleration (using accelerometers) and angular velocity (using gyroscopes). The typical measurement range for accelerometers is +/-16g (that’s 16 times of gravitational acceleration), and for gyroscopes, it’s +/- 2000 degrees per sec. For many applications, this configuration is fine. But there might be some cases where higher acceleration needs to be measured and that goes beyond 16g, like shocks or high impact collisions. Or I might need high-speed rotations to be tracked and 2000 degrees per sec is too low, like measuring the spin of a cricket ball or gridiron football (which can come close to 3600 degrees per sec or 600rpm as demonstrated here by Drew Brees).

Spin rates of a gridiron football during a throw test

As briefly mentioned earlier, hobby electronics stores like SparkFun, Adafruit, or Tindie would be a good place to start when looking for accelerometers and gyroscopes of different specifications. There are also lots of microcontrollers with Bluetooth Low Energy (BLE) built-in that are Arduino compatible so we can program them with the Arduino software. One that I found pretty handy is this one called Blueduino which comes with a Lipo charger add-on (and add-ons are great) and that can be found on Tindie.

The gridiron football sensor prototype using the Blueduino

Final Word

For those who are in research and possibly need Matlab and software support for building custom Matlab programs, definitely check out Sabel Sense sensors (Australia). Else, I reckon the mbientlab sensors would be a great option for starting a custom development. If I get a chance to trial their Metaclinic platform, I will put up another post. Meanwhile, do drop me a message here if you need assistance or advice in any of the options above and feel free to leave a comment if you know of better/different solutions out there. With that, thanks for reading!

The Kayak Tech Survey Outcome

Posted on June 30, 2018 by Julian Chua

Almost 6 months ago, I wrote a short post about (what I thought was) a lack of technologies for monitoring training in flatwater or sprint kayaking. To make sure that it wasn’t just me thinking that way, I created a survey and sent it to a couple of kayaking friends who graciously helped spread the word. I also posted a link to the survey on social media (i.e. Twitter) which I think wasn’t quite as effective. Overall, I didn’t get a big response but it still gave me a peek into things. So let’s dive into it and see what it’s telling us.

Key Stats

So here are some key stats as captured by Typeform:

There were a total of 120 visits, of which 101 were unique and out of the 101, there were 37 responses. This means a 36.6% response rate. Among the 37 responses, 14 were done on Laptops, 23 on Smartphones, and none on Tablets.

Screenshot of Typeform Key stats

Some Details

Then onto the 6 questions:

Training frequency per week – 30 out of the 37 responses said they train at least 2 times a week or more.
Yes/No to use of technology during training – 30 out of 37 use some form of technology to track their training
Regarding the type of technologies they use – 29 use a GPS watch, 19 use a heart rate strap, 8 use a smartphone app, 3 use Motionize, 3 use Vaaka Cadence, 2 use a SmartWatch, and 1 uses a GPS + IMU unit. (note that some people use more than 1 piece of technology)
The number who do not use technology – 5 responded that they do not use any technology and the most popular reason is that they have not tried them
What they liked about their current technologies – Being able to track Heart Rate (n=18) is the top thing that people liked. This is followed by Pace (14), Speed (11), Distance (8) and Stroke Rate (4) (or cadence).
Regarding improvements they would like to see, everyone had slightly different preferences. But in essence, 9 said they would like a kayaking specific device or app, 6 wanted stroke rate available in their existing devices, 6 wants some form of power monitoring (that is affordable), 4 would like to see stroke/technique analysis, 3 wants greater accuracy and reliability in their tracking, and 2 would like a better visual of their data.

[If you would like to see it on Typeform, here’s an overview of responses to the first 4 questions: link]

Even though I only had 37 responses, there was a good mix of opinions; and I take away 3 key things out of the above data:

The GPS watch is the most commonly used tech. It makes sense because it is a multi-functional device – it can be used for running, riding, swimming or just for everyday use as a watch.
More than half (19) of the people use a heart rate strap and it seems most of them value the heart rate data.
Although there are technologies out there that can be used/adapted, 23 out of the 30 still wants some form of improvement to their devices. The most common feedback is there isn’t a kayak specific device or app.

I reckon most people would have a similar setup as the athlete in his Instagram image below – wearing a heart rate strap and with a GPS watch mounted onto the kayak in front of the cockpit.

Tom Liebscher’s Instagram photo (link to original photo)

Additional Info

Also from the few conversations I had with some of the kind people who did the survey, most (if not all) GPS watches don’t track stroke rate, and the accuracy of the speed measurement during short distances/sprints/intervals are not very good.

What I didn’t get a lot of information or feedback about are those kayak specific technologies that are actually in the market like Vaaka Cadence, Motionize and Kayak Power Meter. It seems like not many people have used them. This could be because of the price or a lack of opportunity to try it. I will be digging a little bit deeper into that.

What next

The main outcome I took out of this little exercise is that my initial hypothesis has its merits, and it’s worth pursuing this further. The few options that I am exploring further going forward are (in that order):

Smartphone app (likely iOS)
A kayak specific device like a kayak computer
Garmin Connect app

As this is really just a side project here at ReEngineering Labs, the progress might not be as quick. Nevertheless, it will be moving forward and I will be posting updates every 3 months.

If you are reading this for the first time, please do check out the earlier post here, and have a go at the survey here. If you would like to give your input on kayak technologies or even be part of this project, drop me a message here. To get notifications about this project, simply subscribe on the right.

With that, thanks for reading!

How Technology Helps Measure Soccer Statistics and Tactics

Posted on April 5, 2018 by Julian Chua

Over the last 5-6 months, I have had different conversations with people who are working on technologies related to soccer. And I recall writing about Tactical Analysis in Soccer for SportTechie some years back and thought I will reshare it here plus add a bit of update as some things have changed since then.

What are some of the Football Tactical Analysis Websites?

Squawka is a tactical analysis web application that provides a platform where one can view real-time and post-match statistics of (almost) everything that goes on in a football match. This includes time of possession, number of passes, number of shots, shot accuracy, chances created, tackles (or duels), blocks (or defensive actions), player stats etc. Match analysis data is presented in a field diagram with coloured dots and lines and heat maps. Those statistics can then be filtered by team and player for various types of analysis – whether it’s comparing player performance or looking at shots from one team or overall team events. A useful feature is the timeline scrolling which allows one to look at specific 5 min blocks of match activity.

Player Performance Comparison

Shots – where they were taken and where they landed

Events Heat Maps

The comparison matrix is another interesting tool on the site that looks at stats over an entire season. For example, one can select five different teams in the 2013/2014 season of the Australian League and compare stats that they are interested in. The stats displayed can be filtered by ‘total for the season’, ‘average per game’ or ‘per 90 metrics’. One can also compare teams from different leagues and different seasons.

A special metric of this website is the Squawka Player Performance Score which is calculated using a large amount of data. This player performance score is broken down into “attack”, “defence” and “possession” statistics.

Comparison Matrix Example

Four Four Two also provides match analysis data on their website in their Stats Zone section. It pretty much provides the same data available in Squawka, except the information is presented in a slightly different way and they don’t have a player performance score. The Stats Zone allows all the match activities of a player to be viewed together in the Overall-player dashboard, instead of having to select the individual events in the Squawka dashboard. {Update: unfortunately FourFourTwo has discontinued Stats Zone due to limited resources}

Screen Shot 2014-09-01 at 10.56.06 PM.png

Stats Zone and what their Summary Statistics used to look like

Another site called Outside of the Boot writes commentaries and analysis on selected matches and supports their analysis using statistical data from the above two websites. Other than breaking down the statistics and what was going on in each match, they give reviews on the general style and tactics of a team, player or coach.

Where and how are the data collected?

Regardless of how the data is presented, what’s important is the reliability of the data and where their source is. Interestingly, both sites get their data from Opta, a sports data company that collect, package, analyse and distribute live data. Opta briefly explains on their website that their data collection process is labour intensive with three performance analysts assigned to each match; with one collecting all of the home team actions, one doing the away team and a third analyst checking the data for consistency and adding additional layers of data. They then run a full post-match check within 48 hours to ensure that the database is as accurate as possible.

But what exactly does each analyst do? By using their proprietary software, each Opta analyst puts in the live video feed of a match, then by using hotkeys, every activity that involves the ball is “tagged” – this “tagging” or tracking will record the time each activity started and ended and the X-Y coordinates of the start and end positions. For those who have used video analysis software like SportsCode (now owned by Hudl) or Dartfish, this will sound familiar. But what Opta has done is standardize their activity definition and tracking methods, so every analyst is trained to tag or code the exact same way. This means consistency in the data, allowing every match and every player to be compared using the same standards. The cool thing is, by feeding in historical matches (like all the past world cup matches), they can compare the performance of players from different decades. Check out this video that talks a bit more about what Opta Sports do:

Are there alternative (automated) technologies?

There are a number of athlete tracking technology out there that are either based on wearable technology (Catapult Sports, Tracktics, Polar Team, STATSports & SPT etc) or camera and image processing technology (Stats SportVU and TRACAB). The advantage of wearable sensors is that they can accurately track each athlete’s acceleration and impacts (in three axes) and some even track the players’ heart rate – something that is not possible with any of the current camera or video technology. But data from wearable sensors typically belong to the teams and not shared unless there is an arrangement with broadcasters. With Stats, they claim to not only track real-time 2D (X-Y) positioning data of the ball and the players, but its complex algorithms can also analyse and work out information like speeds, distances, possessions, passings, defence stats and turnovers. So technically, automating tactical analysis to some extent is possible but how much information can be made publicly available is another question.

Some final thoughts

The technology and methods used in Tactical Analysis in football have become more widespread over the years (and its still growing). The statistics that are made available can not only give punters additional information for betting, it can add new dimensions to watching each game. It provides viewers with a better understanding of what the players are actually doing (individually and as a team) and how they have been performing over a season with an unbiased quantified evaluation. For coaches and team managers, it means their decisions (in terms of training, strategising or even talent identification) don’t have to rely too much on gut feel but can be supported with numbers. How much they want to trust those numbers is another thing altogether.

If you know an exceptional app or technology in tactical analysis that is not mentioned here or maybe its still in development, feel free to leave a comment about it, and finally, thanks for reading!

Here are a few other related articles and blogs for those who like geek out a bit more on the topic:

Different Game: https://differentgame.wordpress.com/
Paper on big data and tactical analysis in elite soccer: link
Paper on tactical analysis using pattern recognition: link
Paper on a new tactical metric that looks at effective play: link

Customising What Athletes Wear And Use – 3D Scanning And Other Tech

Posted on March 2, 2018 by Julian Chua

The term bespoke or tailor-made brings to mind an image of a tailor measuring up a customer with a measuring tape so that he can make a suit that fits the customer. Four things typically happen in the whole suit-making process: 1) measuring the customer, 2) picking the preferred materials, 3) making the first fitting and 4) making adjustments based on the first fitting and customer’s feedback. The fourth step might repeat if the subsequent fittings are still not satisfactory. It is a tedious process but the outcome is getting the perfect fit for the customer.

In sports, athletes can have custom made helmets, shoes, protective gear, mouth guards, seats, suits, prosthetics and other adaptive equipment. We are not talking about just having custom aesthetic designs that are unique and represents the athlete. Custom made apparel or equipment that fits a specific athlete’s shape and style can not only improve comfort, protection, their range of movement, aerodynamics and overall performance. Let’s have a look at what technologies or methods are involved in customising them.

3D scanning

3D scanning is able to capture a lot more detailed measurements including curves (down to the millimetres) which standard ‘straight-line’ measurement tools like the measuring tape or vernier callipers are not quite capable of doing. Here are some parts of the body that are 3D scanned in order to be fitted:

The athlete’s head; it can be scanned to create a 3D model, which is then used to design and make a custom fit helmet liner for football players.
The feet are also commonly scanned to produce custom orthotics or high-performance athletic footwear.
The lower body where athletes need to be seated or positioned in a certain way during competition; and it helps with designing custom-fit equipment, enhancing comfort and aerodynamics. (e.g. slalom kayak seat or racing wheelchair seats or a luge)
Stumps (amputations or limb difference) are scanned to help design better fitting prosthesis.

The more common 3D scanners are hand-held scanners like the Artec3D Eva or Creaform3D. They are typically portable and great for scanning around an object or body part. One of the downsides I find is the person doing the scan needs to have steady hands to maintain continuation/tracking and it takes some practice to get a scan right. There are measuring arm scanners that are basically a robotic arm that moves in multiple axes and has a laser scanner or touch probe at the end. The user moves the scanner/probe at the end of the arm around the object and translates the coordinates to a 3D model. It helps with the problem of shaky hands but it might take longer for the probe to travel around the object. Terrestrial laser scanners are capable of scanning an entire stadium but might be an overkill to scan a wrist or a hand. There are also laser scanners built specifically for the foot where the foot is placed into the scanner and the scanning is done in just 15 seconds or less. Another increasingly popular 3D scanning method is photogrammetry. It is a good and cheap option that allows ‘scanning’ to be done with just a smartphone camera and the key factor is really the software.

Kayak Athlete (Jess Fox) being scanned with a Creaform scanner (source: 3D systems)

Moulds

Before 3D scanning, moulds were probably the next best thing to getting the shape of a foot or stump or mouth. In some cases, moulds are still used due to a lack of access to 3D scanning and it is an effective low-cost solution in developing countries. In the case of the mouth guard, getting the mould or impression of the athlete’s teeth and gums is still the best if not the only way to make a custom mouth guard. Athletes can get the impressions themselves using a DIY kit or go to a dental clinic and have the dentist or dental prosthetist ensure that everything is aligned properly. There is also this custom ski boot liner that is designed to be fitted while the user is wearing it and the ski boot liner is injected with polyurethane foam that moulds around the wearer’s feet and solidifies after a short time. If you find it hard to imagine how that works, check out this video about the custom ski boot fitting process that also includes foot scanning and assessment:

3D Motion Capture

Motion capture or MoCap for short is typically used for biomechanical analysis. The typical ‘gold-standard’ MoCap systems are the optical systems. Athletes are (sometimes) made to put on compression garments and have markers placed on the joints that need to be analysed. Then multiple cameras set up around the athletes capture their movement. An example of customisation using Mocap is bike fitting systems. MoCap based bike fitting systems by STT Systems or Retul analyse the athlete’s posture and various biomechanical parameters and recommend an ideal configuration and position. It results in a combination of improved ergonomics as well as performance. Another application that utilises MoCap is golf fitting. The athlete’s golf swing is analysed during the MoCap session and the software breaks down the data and looks at key swing characteristics of the athlete. Then with reference to a huge database of golf swing profiles, a recommendation is generated for the clubs best suited to the athlete’s swings.

Note: There are many other optical (MoCap) systems out there for bike or golf fitting and some of their technology vary and some of them incorporate high-speed cameras. There are also inertial sensing systems and different products will have different levels of accuracy but they all track 3D motion.

An example of a bike fitting mocap system from Bioracer Motion.

Other Complementary Tech

Sometimes, applying any of the above technologies alone is not enough to complete the customisation process and they are complemented with other measurements or sensing technologies.

Pressure sensing technologies are often used for gait analysis and customising footwear. It gives the podiatrist a better idea of how the athlete walks/runs, where the pressure points are and which parts of the sole require more support. They are also used in golf fitting clinics together with Mocap to provide data on the golfer’s balance and pressure distribution during each swing.

3D printing almost goes hand in hand with 3D scanning and we will find in many links or examples above where 3D printing has been utilised to prototype the equipment and sometimes even used as the final product in competition as seen in this paracyclist’s prosthetic leg.

With customisations that are trying to improve aerodynamics, they usually need to perform wind tunnel tests (or aero tests) or simulations. The results of the wind tunnel tests will provide feedback for further design optimisations such as the cycling helmet. And the team at NTNU has even gone to the extent of 3D printing a model of Chris Froome to test and optimise his time trial suit.

Luca Oggiano and the Chris Froome 3D replica in the NTNU wind tunnel (source: NTNU)

Final word

We are in a period where customisation of sportswear and equipment is slowly becoming a norm. Other than the improvement of technologies and processes involved in customisation, the mindsets of athletes have also shifted to see the benefits of wearing and using tailor-made equipment. With major shoe companies like Nike, adidas and New balance partnering with technology companies to further explore performance centred customisation, it will be interesting to see how the technologies will progress and what boundaries can be pushed with customisation.

What else do you think could be or should be customised for an athlete? Would you like to explore making something unique or bespoke? Do leave a comment or feel free to reach out. With that thanks for reading!

Technologies Used To Monitor Training In Sprint Kayaking [Survey]

Posted on January 20, 2018 by Julian Chua

What is Sprint (or Flatwater) Kayaking

In case you are haven’t heard of the sport, Sprint Kayaking isn’t the most popular sport in the world. In fact, it isn’t a very easy sport to get into. For example, if I am new to the sport, I might need to join a club to get access to the equipment and training programs. Then I would sign up for an introductory course of sorts to learn the basics of kayaking on the water and safety in the water. After I sort out the basics, which is probably done on more stable kayaks, I will try to move into the kayaks designed for sprints. These sprint kayaks will be a lot more tippy but they allow the trained paddler to go on the water really quickly – hence the name sprint kayak. The length of the process from being new to the sport to being able to comfortably paddle on a sprint kayak will vary between individuals but I would say it is between a few months to a year. Then to be really good in the sport will take years of training or 10,000 hours as Malcolm Gladwell popularised in his book Outliers. [There are many debates on the actual number of hours (to become an expert in anything) but the point is: it’s hard work.]

My own brief experience in the sport

Years ago when I was in the sport as a teenager, the only technology we used was the stop-watch that took the time of our 200m/500m/1000m sprints or it was used as a timer for doing interval sessions. Back then, I only competed at the national level and never went further. Work and life commitments took over and I even moved to a different city. Now with a young family, having time to go flatwater kayaking is quite the luxury.

my first kayaking session of 2018

Here comes the “tech” bit

But being a sports engineer, I recently revisited the use of technology in sprint kayaking training and was thinking of a couple of ideas of adopting technologies that are available in the market to help with training. I did a bit of research and it seems like most kayaking people use products that were designed for runners or cyclists to track their training. A commonly used product is the running/cycling app Strava. I know a handful of people who secure their Garmin (or other fitness) watches onto their boat and simply start a “run” to track the session. The data then goes onto the Strava platform or any other platform they use.

my “run” on Strava

Nelo has a training app that paddlers can use by securing their Android phone onto their kayaks and it uses GPS and the motion sensors on their phone to track their training. The great thing about their app is that it incorporates a Coach’s app that monitors up to 6 different paddlers. There are also a couple of iOS apps on the market that tracks water sports of various kinds including waterspeed app or paddle logger. These ones are a bit more generic.

Then there’s also sensor products specific for paddling sports such as the Vaaka Cadence sensor, the Motionize sensor, and the Kayak Power Meter.

There might be some more that I haven’t come across or they are only used in research labs at the moment. But even with what seems like a good range of training products, I still feel that there is something missing with all these different products. Maybe it is just the sports engineer in me that thinks that way. I am keen to speak to other canoeists/kayakers/paddlers out there who may or may not use technology in their training and get some feedback.

So if you are a canoeist/kayaker/paddler, could you please fill out this survey: link. Your time and input will be much appreciated and will help shape the future of any tech that’s developed! If what I talked about here interests you, leave your email at the end of the survey and I will keep you posted on future developments. Lastly, please also forward this to your fellow canoeist/kayaker/paddler friends. Thanks!

Do Force Platforms, Pressure Sensors And Smart Insoles Do The Same Thing?

Posted on May 26, 2017 by Julian Chua

Force platforms, pressure sensors and smart insoles are all devices that a person can step on and get some insight related to their weight or the pressure they are exerting on those devices with each step. Other than that, they are quite different and can have very different applications. This post is just an attempt to break that down. Feel free to jump to the different sections that are of interest:

[Force Platforms – Pressure Sensors – Smart Insoles – Summary – More on Smart Insoles]

Force platforms

A Force Platform (FP) is an equipment that you would typically find in a lab – an engineering lab, a biomechanics lab, gait analysis lab, ergonomics lab.. you get the idea. They are great for measuring forces applied directly onto its surface. So when a force platform is placed on the ground, you could step on it to find out how much force you are exerting on the platform. For those platforms that measure multiple axes, you could also slide an object across the platform to measure resistance forces between the surfaces. In sports engineering, FPs enable studies in walking/running gait, jumping (and landing), friction measurements in water polo balls or shoes or gloves, the coefficient of restitution of balls, aerodynamic drag (when placed in a wind tunnel), and more.

An example of a Kistler Force Platform (blue) set up in a wind tunnel

For anyone keen to explore what else is done with force platforms in sports engineering, feel free to do a quick search on these journals: Sports Engineering Journal, Sports Technology Journal or Journal of Sports Engineering & Technology.

Inside Force Platforms

The majority of Force Platforms in the market are set up with multiple Strain gauges or Piezoelectric sensors/elements that deform proportionally to the applied load. There is also the not so common Hall Effect sensing Force Platform which doesn’t require an external signal amplifier/conditioner like the strain gauges and piezoelectric sensors do. They are typically quite expensive and their prices vary with the number of sensors, size, construction, and additional data acquisition (or signal amplifier) systems.

For those who can’t afford the expensive systems and is adventurous enough to try and build something, a sports physics researcher from the University of Sydney wrote a paper providing details of a cheaper home made force plate. Essentially he used Piezos that were manufactured for sonar applications and they cost $25 each. A quick search on Instructables also showed one DIY instruction on making a strain gage force plate. For the slightly less adventurous, there is also the option of the Wii Balance Board as a cheap force plate alternative. There have been some validations of the gaming platform as a standing balance assessment tool, a golf swing analysis tool, and for use in other medical applications. The only downsides of the Wii Balance Board are the user weight limitation and that a custom software is required to access and read the data.

Pressure sensors

There are three main differences between Pressure sensors and Force platforms. Pressure sensors are typically flexible and can be placed on flat or curved surfaces, unlike Force platforms that have to be mounted rigidly. The other difference is pressure sensors do not measure force vectors. Thirdly (or a slight extension of the second), Pressure sensors only quantify pressure that is perpendicular to it (single axis) so it cannot determine shear forces or friction between two surfaces. Due to their flexibility, pressure sensors have been used to determine comfort and fit in aircraft seats for Paralympians, analyse medical mattresses, measure the pressure of grip during a golf swing, pressure distribution on bicycle handlebars, and more.

Single force sensitive resistor (FSR) from interlink electronics

Pressure sensors are mostly made out of either resistive sensors or capacitive sensors. The main differences between them are the sensing material used and their electrodes. They can be constructed as single sensing nodes or they can also be constructed in a row-column array fashion. The advantage of the array or matrix construction (over single nodes) is that it requires fewer connections. In an array, the intersection between each row and column is a sensing node. So a 3 by 3 array creates 9 sensing nodes while only needing 6 connections. On the other hand, 9 single sensing nodes will need 9+1 connections where the +1 is the common ground. The difference becomes much bigger as the number of sensing nodes increases (For example 100 sensing nodes can be achieved using a 10 by 10 array that needs 20 connections or 100 single sensing nodes that need 101 connections).

A simple illustration of Single sensing node Vs Sensor Matrix/Array

However, the matrix construction is not without its challenges. The matrix sensor circuit is prone to parasitic crosstalk (capacitive or resistive). This means when pressure is applied on one node or multiple nodes, the electrical readings for other (unactivated) nodes might be affected. This is also known as “ghosting”. Unless some correction is applied, the measurements/readings become inaccurate and potentially useless. Also, the bigger the matrix, the more complex the correction. But if accurate absolute readings are not required, then it’s fine.

A related side story

I have been following the development of this smart yoga mat that was successfully crowdfunded on Indiegogo back in Dec 2014. Fast forward to 2017, they are still struggling to deliver the product. Looking through their updates, we can see they had to deal with sensor accuracy (possibly the crosstalk or ghosting issue); and on top that, some other issues they had include sensor durability, mat materials suitability, and accuracy of their tracking algorithms (which they are using some form of AI). Having prototyped a smart exercise mat around the same time they started, I can fully understand the challenges and why it is taking that long. Then again I am not sure it is worth all that effort. Personally, I think that simply relying on a pressure sensing mat to monitor and give (technique) feedback on yoga poses (or any exercises) has its limitations. Adding camera tracking (possibly utilising the camera on the tablet) might help. That saying, it is not stopping others from developing similar products as seen in this video.

Smart Insoles

Smart Insoles or Instrumented Insoles are essentially pressure sensors made in the shape of a shoe sole. The sensors are usually made in a similar fashion described earlier. Most of the Smart Insoles are also built with IMUs so that it adds a bit more context to the pressure data such as whether the wearers are standing, walking, running or jumping. The greatest advantage of Smart Insoles is they allow feet pressure mapping and measurement on-the-go. Things like continual gait analysis and activity monitoring, and it even has medical application likes foot ulcer prevention and falls prevention.

Source: Footlogger.com

There are a couple of shoemakers that designed their shoes with the Smart Insole embedded within the shoe like the Altra IQ for running and the Iofit for tracking golf swing stance. The good thing about them is they have designed everything to fit properly into a shoe, made for a specific function. So users don’t run the risk of their Smart Insole not fitting properly into their shoes and collecting inaccurate measurements. On the other hand, users are restricted with specific shoes for pressure monitoring or activity analysis. But at the end of the day, the pros and cons are really dependent on the individual.

Brief Summary

Going back to the question: “Do Force Platforms, Pressure Sensors and Smart Insoles do the same thing?”; there are some things that they are all capable of performing (e.g. gait analysis), but they all do it in a different way. Also, there are certain measurements or monitoring that are unique for each sensor. Here’s a simple table that sums it up:

Sensors	Measures shear force	Measures Pressure	Doesn’t require rigid mounting	Portable	Tracks Motion
Force Plates	✔	✔	X	X	✔/X
Pressure Sensors	X	✔	✔	✔/X	X
Smart Insoles	X	✔	✔	✔	✔

More about Smart Insoles

Personally, I feel that Smart Insoles is a great idea, with many useful applications in sports and health. Over the last few years, there has been an increase in research and development in this area with many patents generated in the process; and companies around the world have come up with commercial products around the concept of Smart Insoles. It is definitely still in its early stages and I am not sure if it has even reached Early Adopters yet. Sadly, one company that I followed (Kinematix) has already closed shop due to a lack of funding. Perhaps it is ahead of its time like the adidas intelligent running shoe with intelligent active cushioning. Nevertheless, I believe the potential (of Smart Insoles) is there and I think targeting specific niches/problems will probably have a better outcome than designing for a generic application.

If you have an idea or project needing a smart insole or custom pressure sensor, feel free to contact us or leave a comment. We might be able to help you with it or at least point you in the right direction. As always, thanks for reading!

This post also appears on sportstechnologyblog.com: link.

Accelerating Sports Technology Development And Innovation

Posted on April 14, 2017 by Julian Chua

Roughly 4 years ago, I wrote a post about crowdsourcing sports innovation – how sports companies and organisations were inviting people with ideas to step forward and pitch their innovations. Fast forward to 2017, the ways of generating new sports tech ideas have grown and evolved. From sports hackathons to accelerators, incubators, and Meetups, and online communities and invite-only/secret-squirrel investment funds or a mash-up of 2 or more of the above. I am definitely no expert in this area but based on my very limited experience, here’s a look at a few of the possible ways to accelerate sports technology development and innovation.

Hackathons

One way of defining hackathons* (from HackathonAustralia) is this: “Hackathons are competitions that challenge people to create something over a set time period using technologies.”. So in the case of a sports hackathon, that “something” created would be an innovative sports tech solution that meets an existing need/pain. It could be a hardware solution or a software solution or both.

[Themes] Depending who is organising or sponsoring the hackathon, events could have a specific theme/focus like the Western Bulldogs hackathon that provided participants with their athletes’ GPS data to do further analysis or the Future Of Sports Tech Hackathon by Enflux that allowed participants to use their motion capture technology or the Hack4Sports that had a focus on building sports tech startups.

[Needs Assessment] Whichever the theme, the participants would require some guidance/directions on real needs vs good-to-haves. That’s where industry experts and end-users (sports clinicians/analysts/coaches etc) who are at the event, can offer that perspective. This could be through talks or interactive workshops on specific areas such as improving performance or injury prevention or increasing participation etc.

[Forming teams] Following that, teams need to be formed to design the solutions. Some participants might have already formed teams prior to signing up to hackathons. But it is quite common for people to rock up by themselves. So hackathons might dedicate a session for team-forming. Typically people who have a passion in the same area would team up. Other than that, it is also helpful to have a good mix of hackers, hipsters and hustlers in the team.

Hustler, Hipster and Hacker

[Pitching Comp] Most hackathons involve a pitching competition which means the solution (created within that 1 or 2 days of hacking) has to be validated with real life users/customers and has a potential market fit. The team with the winning pitch usually wins something that can help them take their idea further. That could be prize money or often they get to be part of an accelerator program to develop that Lo-fi prototype into a minimum viable product (MVP). Else they at least have bragging rights.

[If you are interested in a sports hackathon, please complete this SURVEY]

Meetups

Sports Tech Meetups (literally on the Meetup site) are to some extent scaled down versions of hackathons and/or pitching competitions. It is usually a local group of sports tech-minded people getting together once in a while to do stuff such as pitch nights or show-and-tell or have people already in the industry sharing their insights and experience. There are no fixed rules and format which makes it quite casual and there are no barriers to joining a meetup other than geography. All you need is an interest in sports technology.

[Here’s a couple of examples: Melbourne Sports Analytics Meetup, Seattle Sports Tech Meetup]

This makes Meetups a good platform for people who are new to sports tech to come explore the field, network and learn more. It is also good for people who have developed a concept or MVP to come and get feedback from others (through pitch nights or show-and-tells). The next steps for these people could be to take part in a hackathon or join an accelerator program or incubator.

Online Communities

I believe this is quite plain and doesn’t require much explanation. There are quite a number of online platforms that allow people with an interest or a stake in sports technology to be a part of. From Google Groups to LinkedIn Groups to Facebook Pages. But what I observed (at least on LinkedIn Groups) is that there are very little open discussions within the groups/pages. In most cases, article posts get “Likes” or 1 or 2 Comments. Sometimes the posts are just companies trying to promote their products and services which often gets no “Reactions” whatsoever. So I am not sure if these groups are any good at promoting or even accelerating innovations in sports tech.

There is another online platform that has been growing in popularity (in the last few years) especially in the startup community – it is an invite only platform called Slack. Basically, it is meant to be an internal chat system for team members of an organisation to have work/project discussions. But one sports technology startup group that call themselves Starters decided to jump on this platform and allowed anyone who is in a sports tech startup (or trying to build one) to sign up to be part of the group. Though there is a fee to get in, it’s mostly to ensure that only people who are seriously interested join.

But what is happening within this Starters Slack group is quite phenomenal. Ideas are exchanged, there are open discussions, Ask Me Anything (AMA) sessions, connections and introductions are made online, followed with meet-ups in real life, actual events (hackathons, accelerator programs & meetups) are organised and promoted, and I am sure there is more happening between individuals through direct messages (DMs). What’s amazing is that though it’s mainly based in the US, there are individuals and companies participating from all over the world.

Starters – a global sports tech startup community

Slightly similar to Starters is a SportsBiz slack group started by the SportsGeek from Melbourne.The main difference is that there is slightly less emphasis on startups or sports technology and more on sports business in general. But the objective is not that different – to use the platform for sharing ideas, finding collaborators and opportunities, and ultimately pushing the sports industry forward.

Some Key Points

So there are a few key points that I take out of this. One of it is, we need to collaborate. No one can build anything great on their own. Not only do we need a diverse team with different skill sets, we need input from other people (locally & globally) or run the risk of tunnel vision. Secondly, competition spurs innovation. Which is quite apt since we are talking about sports technology here, where one of the aims of it is to help athletes perform better and win the competition. Lastly, none of the avenues on its own can be the be-all, end-all of this topic. Especially if we are talking about building successful long-term sports tech enterprises. People at different stages of their ideas or development would probably go through a different process. What may work for some may not work for others. We may need to change from something that doesn’t work anymore (e.g. LinkedIn Groups) to something else that does (e.g. Slack).

I know I haven’t commented much about accelerators and incubators. That’s mainly because I have not had any personal experience with them. What I do know is that you need to at least have a team (and not just a great idea) to be part of an accelerator and preferably an MVP to join an incubator.

Finally, I think for someone who: has a few good ideas, is passionate about (or has some exposure to) sports technology and doesn’t quite have a clear direction or built a team yet, a sports hackathon can be a good place to start. This is something I would like to explore a little more. So if you think the same way and would like to take part in a sports hackathon (or not), or if you have other thoughts on accelerating sports technology innovation, do help me out and complete this SURVEY or leave a comment or drop me a message on Twitter or LinkedIn. With that, thanks for reading!

This post can also be found here

*Hackathons have also been known as hack days, hackfests, startup weekends, makeathons, design-athons etc.

Re-Engineering Labs

Author: Julian Chua