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 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!

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!

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.

Versus Fitness: Developing A Smart Gym

Posted on May 4, 2015 by Julian Chua

Over a year ago, I wrote a post about developing with the Kinect and how I was working on a project that revolved around it. Fast forward to today, the project is now an officially launched gym that is also known as Versus Fitness.

What is Versus Fitness?

Versus is a system that has gamified fitness. By utilising different sensors and technologies, it is able to measure 3D motion, pressure, force, acceleration and power output of over 200 different gym exercises (and counting). With each proper repetition (or rep) that is executed, the user not only gets the rep counted by the system, a score is given based on the above measured parameters, and the score is scaled based on the user’s weight and height. In that way, 2 people of different weight and height doing the same workout can compete against each other on almost equal terms (Hence the name Versus). In case the term “wearable technology” comes to mind, no, there is nothing that the users need to wear to get their exercise tracked (maybe except a heart rate monitor, but that is purely optional). Just check out the video below.

How I got involved?

I started working on the Versus Fitness gym since late 2013 and it was purely by coincidence. Someone who knew Brad Bond (the founder of Versus Fitness) was at the RMIT Sports Engineering Lab on one of those Uni open days and he saw a novel sensor technology that would suit Versus. After a series of meetings and discussions, a research contract was set up to further develop that technology for Versus. This was partly funded by the Victorian Technology Development Voucher. At the same time, they were also looking for an additional team member to work on motion tracking algorithms. That’s where I came into the picture. Long story short I was offered a contract role on the Versus project which was partly funded by the Enterprise Connect – Researchers in Business grant (this has been replaced by the Entrepreneurs Infrastructure Programme). Kudos to Aaron Belbasis who was a key connector/initiator who brought everyone together and who was also one of the key researcher who helped develop the novel sensor tech. There’s a bit more details about the RMIT-Versus collaboration here.

What Tech are we talking about here?

One of the sensor technologies came from the research collaboration mentioned earlier. The team at RMIT calls it a “sensor-less sensing platform”. The closest thing would be Force Sensitive Resistors (FSR) like the ones from Tekscan. If you had a proper look at the video above, you will see the “sensor-less sensing platform” used in the floor exercises and some of the running exercises. Basically its a sensor that measures pressure.

There are other sensors that were developed or customised for tracking motion and a number of them are available off the shelf or at least purchasable online. In fact some of the sensors (like load cells and accelerometers) are similar ones typically used in the manufacturing, or automotive industry. A lot of custom fittings, enclosures and mechanisms were designed for the sensors before they could be installed in the gym. Majority of the design were done in-house and prototyped with the help of a MakerBot replicator.

But what really made the sensors (tracking system) worked effectively are the smart algorithms that processes all the sensor data and accurately identifies when each person is performing the exercise properly and evaluates how well he/she has done it. Initially when designing the algorithms for tracking each type of exercise, it all seemed pretty straightforward; but as things progressed, it turned out there were quite a few more considerations – e.g. filtering out “incorrect” movement data that resembled an actual rep, or profiling movement data from users of different abilities (or fitness level) etc.

Perception & Reality

Another important part of the system is the “gaming interface” or the “gaming control centre”. It is the personal trainer’s assistant. It relays to the users what exercises to do, records their performance, stores the performance data in a database, reminds the user how well they did previously (their Personal Best), manages the equipment (to some extent), and ensures that every exercise station is in sync so that the workout runs smoothly. That allows trainers to focus on one of the things they do best: ~~scream at~~ motivate people.

So with the combination of the sensors, smart algorithms and the gaming interface, this means: real-time tracking, with feedback of the users’ performance (score) or technique delivered right after each completed rep, and an overall quantified workout so users know how well they fare compared to their previous workouts (and with other users).

Future Developments?

The very first Versus Fitness gym is based in Moorabbin and that has seven different exercise stations (as seen in the video above). One could call that the full Versus experience. There are a number of possible developments in the pipeline. One is the development of new exercise stations to increase the type of exercises that can be tracked. Also, there are possible opportunities to customise the system for the elite or professional athletes, or even rehabilitation applications. Something that is definitely in the works is a “multi-station” concept – a single exercise station that has several sensor solutions allowing tracking of a few different types of exercises (e.g. dumbbell, kettlebell & floor exercises). This significantly reduces the footprint of the equipment and would suit small gym spaces. In fact this is currently on trial in a gym somewhere in Australia, and depending on how things go, you might start finding the VS logo in many more places!

A Look at Smart Balls

Posted on July 26, 2014 by Julian Chua

Tracking how fast a ball was kicked or thrown used to be done with an external device – it could be a speed radar or a high speed camera or maybe even a very trained (and experienced) eye. However, in the last 5-6 years, more and more engineers and scientists have tried to put some form of sensors inside the balls to measure linear velocity, spin velocity, spin axis. This has mostly been made possible with advanced developments in microelectromechanical sensors (MEMS), where accuracy and measurement range has increased significantly (while still keeping the small form factor). Another 2 tech contributions that helped keep the sensors (more permanently) in the balls are wireless connectivity (Bluetooth or Wifi) with the micro-controllers and wireless charging.

Smart Ball Construction

Although the electronics is key to measuring movement signals and processing, there is still the very important task of holding those components (sensors + micro-controller + wireless modules + battery) inside the ball. Let’s call all those components the core. So while designing a method to secure the core within the ball, one has to consider the weight and position of the core and how it affects the centre of mass of the ball. The method has to be robust enough since the ball will take lots of impacts as it’s kicked or thrown or bounced. The method of securing the core will also affect or determine how the ball is constructed. Here’s a look at some of the different type of “smart” balls and their construction:

Smart Basketball: 94Fifty

Image from their patent file

The way that the 9DOF sensor is built into the 94Fifty ball is rather unique (thus the patent). According to their patent application, there is an inner cavity on the surface of the inside of the ball, which is purposed for a casing to house the electronic components (core). The casing is built with a flexible material such that the walls can flex with the pressure difference between the inside of the bladder and the inside of the housing. The patent application also mentions providing access for battery charging but that was probably the early version. The new version is built with Bluetooth connectivity and wireless charging.

The ball is constructed according to the official size and weight which is 29.5 inches (749.3mm) and 22 ounces (623.7g). So with the extra weight added from the core, the designers made adjustments to the enclosure material so that the overall weight is close to the standard weight, and more importantly, the weight distribution is compensated so it spins like a standard ball. For example, if the core is positioned at the top of the ball (see image above), and the valve is placed 180 degrees from the core, the extra weight would be added around the valve until the balance is achieved.

Smart Soccer ball: adidas micoach

adidas miCoach Smartball

adidas’ smart ball is designed with its core positioned within the ball and held there by what looks like 12 sets of supports. The core is positioned or suspended right in the centre of the ball, and the supports are meant to be rigid so that the core is always in the dead centre. There doesn’t seem to be any patent related to the method of supporting the core but there was a patent with regards to the electrical wiring within the ball. The patent basically describes how the wiring is arranged along the bladder wall to interconnect two electronic devices. It also mentions that the electronic components are arranged in such as way that the ball is balanced and doesn’t affect playing properties of the ball. According to the adidas page, the core consists of only a tri-axial accelerometer. There is also wireless charging with their custom induction-charging stand. The induction coils would likely be placed along the bladder wall instead of in the core.

Smart Cricket ball

The Sportzedge group at RMIT developed an instrumented cricket ball for measuring the spin rate and calculating the position and movement of the spin axis (link to the conference paper). Due to the high spin rates of wrist spinners (up to 42 rps or 15,120 deg/s), typical off the shelf gyroscope sensors can’t manage that measurement range. What this smart cricket ball has are three high-speed gyros that can measure +/- 20,000 deg/s, one for each axis. This ball is not built in the typical manufacturing process. In order to house the electronics, meet weight requirements, and keep it balanced, 2 solid halves of the ball were designed and CNC machined from the material Ureol or RenShape® BM 5460 which had the right density and hardness. Eight holes within the ball allowed for additional masses to be inserted to balance the ball. According to the paper, this design is an initial prototype and it is still not robust enough to be hit by a cricket bat. But it is fully capable of measuring spin rates during fast bowling. Subsequent versions will be more sturdy and also include wireless charging.

Instrumented cricket ball (source: Fig 1 of the research paper)

Smart Oval Ball

Smart AFL ball

The same team that built the smart cricket ball also developed a smart AFL ball to assess angular flight dynamics and precision of kick execution. The same electronics (high-speed gyros) that were built into the smart cricket ball was also incorporated into this smart oval ball. The main difference is, this oval ball is made with two bladders that sandwich the core electronics, keeping them right in the middle of the ball. The bladders were inflated simultaneously to ensure a more even distribution of pressure. It was noted in their paper that the advantage of using an inflatable bladder (instead of replacing it with expanded polystyrene beads) is that it allows for realistic kicking whereas the foam beads will absorb too much energy thus dampening the performance. Other than the smart AFL ball, a recent patent search found another American style football that is built with an electronic circuit coupled to an inflatable bladder. Interestingly, the football in this patent is designed intentionally with the electronics causing imbalance, unlike the above designs where the creators made sure their balls are balanced. Even though Wilson Sporting Goods has been granted this patent, there has yet to be any news of them releasing an instrumented oval ball. This might be something to look out for?

Ball Movement Measurements

No smart ball is complete if there are no “smarts” involved. The acceleration and/or angular velocity that is measured do not mean much if they are not processed and analysed. So firstly, the inertia sensors would require calibration – to ensure that the measurements are linear and accurate or at least corrected based on a benchmark device. Then mathematical models would be derived to determine the parameters for analysis; parameters such as spin rate, spin axis, speed, timing, ball flight path, angles, point of kick, bounces etc.

Also, to ensure that relevant data is processed accurately, certain “markers” or references are put in place to indicate when ball movement needs to be analysed and how it should be analysed. For the smart cricket and AFL ball developed by RMIT, as they are still in the research stage, a lot of the sensor measurements, signal processing, calculations and analysis are done manually. However for the commercial products like 94Fifty and the micoach smart ball, they have developed algorithms as well as guided user interface and instructions to make sure that each throw or bounce or kick is analysed accurately. In both cases, the interfaces and algorithms come in the form of an iPhone or iPad app. Here’s a breakdown of how each ball does it:

Basically to analyse a kick with the adidas micoach ball, the micoach app needs to be turned on and connected to the ball via bluetooth. Then after the ball is positioned stationary on the ground, the user has to select his/her kicking foot and tap on the ‘Kick it’ screen before executing the kick. One condition for getting the parameters measured is to kick the ball at least a metre off the ground and for it to travel at least 10m. No bouncing or rolling kicks.

Similarly the 94Fifty ball requires its app to be turned on and connected via bluetooth for the shots to be measured. For measuring shots, the user’s height needs to be entered into the app as well as the distance where the user is shooting from. There are options in the app to utilise a shooting machine or a user can practice with a training partner who can pass the ball after each shot. The only condition is that the pass has to be a chest pass for the subsequent shot to be recognised by the app. There are also some workouts or skill trainings that allow users to practice on their own and ball handling tracking options.

The Coaching Element

All these sensor-laden balls and their accompanying apps with smart algorithms aims to help users become better players – whether it is improved technique in kicking or shooting or training of muscle memory to perform proper mechanics over and over.

The 94Fifty app provides real-time audio feedback for each shot that a user makes, whether the focus is on shot arc angle or shot speed or shot backspin. Based on ideal stats (e.g. arc angle of 52 deg and backspin of 180rpm), the user can fine-tune his/her technique to achieve the right angle/speed/backspin. This user shows how by utilising the app’s feedback and capturing his practice on video at the same time, he could analyse his shot mechanics and identify how he could correct his shooting technique.

Likewise, the adidas micoach smart ball app not only measures each kick with ball speed, spin, spin angle, ball strike location & flight path, it also provides “Coach Notes” with recommendations on how the user can boost each specific parameter. A video option within the app allows a second person to capture the user’s kick using the iPhone/iPad’s camera so that the user not only gets the kick statistics but also visual playback of the kick.

Bottom Line

Designing a smart ball that analyses a player’s performance is definitely a complicated process. Not only must the instrumented ball behave like a normal standard ball with proper balance, but the electronics incorporated within the ball also have to be held robustly so that they don’t break under impact and the sensor data remains repeatable and reliable. Then there is the task of working out what parameters can be determined from the sensor data, if constraints/markers/references should be put in place to ensure accurate measurements, and how those parameters are helpful for improving an athlete’s skills and techniques.

Even with a properly designed ball that measures all the critical performance parameters accurately, it’s probably still not a complete coaching system. What the ball (and app) lacks is the ability to know (and break down) what exactly the athlete did in his kick or shot to achieve the numbers as calculated by the app. For example, in football, what affects a kick include foot speed, which part of the foot kicked the ball, and the amount of upper-body movement; and in basketball, a few things that influence a free throw include: the amount of trunk and knee flexion, shoulder flexion and elbow extension. These range of movements could be tracked with either video analysis (such as Kinovea which is markerless) or a 3D motion tracking system (such as Vicon which requires markers), or wearable sensors (such as SabelSense, XSens or this new sensor embedded compression suit).

In a nutshell, smart balls are definitely great coaching tools. But if combined with athlete movement tracking, it would give a lot more insight to improving the athlete’s shot performance.

Developing with Kinect sensors for fitness and health

Posted on January 3, 2014 by Julian Chua

The Kinect sensor has been widely used (hacked/developed/applied) by many ever since the Xbox 360 was first released. A couple of years ago, a fellow sports engineer from SHU studied the feasibility of using the Kinect sensor as a biomechanical analysis tool. He concluded that although the Kinect was fairly accurate, it wasn’t good enough for serious analysis (You can read more in his blog post here). The main advantage of the Kinect was (and still is) it’s price compared to professional motion sensors, and the Microsoft SDK which allows developers to come up with interesting applications (Check out various kinect hacks here).

I recently started working on a project that utilises the Kinect sensor. The project is basically developing a fitness product/system that combines the use of various sensors for assessing gym exercises. It is a rather interesting and novel concept because not only does the product quantify different gym workouts, it has a gamification portion where each user is competing with another gym user at the same time. No, it’s not like online gaming. In fact, this system is not designed to be used at home, but rather in a gym setting where participants perform the workouts together and get scored at the end of each session. Think Nike+ Kinect Training but for many people physically at the same place and with smart gym equipment (Equipment with sensors and smart algorithms). I probably should not go into too much details to avoid spoilers, but do look out for it’s launch sometime this year!

Nike+ Kinect Assessment

Anyway, I had the opportunity to test out the Nike+ Kinect Training (NKT) and found that it has quite a well designed interface that helps the user perform workouts with proper techniques. For example, the Kinect (ver 1) sensor is not the most accurate in measuring depth, so for exercises like push-ups, burpees, and core exercises like the bird-dog, the NKT gets users to turn to the side instead of face the TV/Kinect sensor; that way, the user’s movements are tracked more accurately. The concept of the NKT program is also pretty good because it starts with putting the user through an assessment – a series of movement tests and exercises, then rates the user in terms of strength, flexibility and stamina. Following that, it recommends a scheduled training program with a combination of exercises that can help you reach your goal (either to build power, become toned or lean). The feedback given by the on-screen personal trainer are usually quite spot on, usually correcting my posture, asking me to slow down (for exercises that are meant to be controlled) or speed up (for endurance type exercises), or just encouraging me to push on for the last few reps. There are instances where the Kinect sensor was unable to track some of my joints accurately and failed to count my reps, especially in a few of the floor exercises. But all in all, it is a pretty good program based on some sports science fundamentals and it could be an effective training tool for people who like to workout alone. I also got some good ideas off it that might be useful in the project I am working on.

{On a separate note, there has been some interesting devices/gadgets developed for the fitness and strength training folks in the last few months:

PUSH – a wearable arm band (possibly built with inertia sensors) that is able to determine force, velocity and power of each strength training rep
Hexoskin – another wearable smart apparel that not only measures movement (activity level, steps, cadence), but also the users physiology (heart rate and breathing rate).
Athos – similar to the Hexoskin, it is a wearable smart apparel with the addition of electromyography (EMG) capabilities embedded in the apparel.
Skulpt Aim – a mobile device that measures the user’s body fat percentage and muscle quality in individual muscles.

These devices (and other smart devices) could potentially become a common sight in gyms in the near future, allowing users to track more about their workout sessions and gain more understanding of what’s happening. A common trait among these gadgets is that they all have (or are developing) iPhone apps, which means users will have access to their workout history on their fingertips and probably be able to brag about it on social media.}

Going back to the Kinect sensor, apart from sports and fitness applications, developers have also come up with practical solutions for the medical and health industry. One such application is the Teki system developed by technology services company Accenture, and a few other partners including Microsoft. The main purpose of the Teki system is to reduce the need for elderly patients to travel to the hospital for routine consultations and check-ups, saving time and money. Using a Kinect sensor, set up at the elderly patient’s home, together with a few other wireless medical devices like a pulse oximeter and a spirometer, the doctor is able to do a remote consultation using a webcam in the hospital/clinic. The Kinect sensor comes in when the doctor needs to evaluate the patient’s range of motion; or when there are prescribed rehabilitative exercises that the patient need to perform and the Kinect sensor is able to assess and provide feedback to assist the patient.

Kinect v2

It was mentioned earlier that the Kinect sensor isn’t the most precise in measuring movements, especially in terms of depth and also higher speed motions. Although the specification says that it could measure up to 30 fps, but after testing it myself, I found that it is usually around 15-16 fps (depending on your program). Lighting and certain background objects could also affect the detection of a full skeleton. But all these little ‘glitches’ will no longer be there with the release of the new Kinect 2 sensor which features improved performance over the original Kinect. Those improvements include: a wide-angle time-of-flight (ToF) camera allowing better range (or depth) measurements; capturing 1080p video, and ability to ‘see’ in the dark with its new active IR sensor; it can detect more joints on the body (5 more than the previous) with much higher accuracy, and it can track up to 6 skeletons at one time. Also, it is capable of measuring the users’ heart rate via a change in the user’s skin tone and even detecting mood from the user’s facial expression. {Just watch this video that basically demos all the improvements.}

With this newer Kinect sensor, it will be a lot more exciting for hackers/developers and who knows what interesting applications could be invented. But as of now, there is still no news of when Microsoft will officially release the windows version of Kinect 2 for developers; for those who are really keen, there is a preview program with limited spots that you can apply for here!

If you know any other Kinect applications in sports and health, feel free to comment below. Thanks for reading and here’s wishing everyone a happy new year!

Designing an iPad Cooling Case

Posted on November 10, 2013 by Julian Chua

A while back, I was referred to someone who had an issue with overheating iPads (the 3rd gen one). Due to the nature of his work (coaching/sports science), he often uses the iPad under the sun, which contributes a fair amount of heat to the iPad, and it was overheating to the extent that it would shut down. The shutting down was meant to be a safety feature to prevent it from blowing up, but this became a huge inconvenience for him. So the challenge for me was to come up with a solution to cool down the iPad so that he can continue using it under the sun.

RESEARCH

First I did a bit of research on the internet, and found that the new iPad (3rd gen) did have an issue with overheating. An article from Reuters even found that the iPad racked up temperatures of up to 47 deg Celsius after 45 minutes of running an intense action game. It didn’t bother most people (from what I read on the forums) because they will just stop using the iPad when it got too warm and let it cool down, or use it on the table instead of holding it with their hands. But for someone who needs to use the iPad as a sports training tool under the sun, it was a problem.

DESIGN RESEARCH

Next I explored the possible options for cooling the iPad:

Cooling with water – People who overclock their PCs are usually the ones who would try using a water cooling system. You could build one on your own, or buy a system off the shelf. It will work for a PC, but an iPad? I am not too sure. I think one thing for sure is it will make the iPad way too bulky.
Using an ice pack – Anything that is zero degrees should cool things down. But, the thing is, it will also cause condensation. There will be water droplets everywhere, your hands gets slippery and oops, you drop the iPad on the ground. Not a good idea.
Heat sink – Heat sinks are only effective if there is complete contact between the hot surface and the heat sink; and typically that is achieved by applying heat sink compound or thermal paste between the surfaces. Also sticking a couple of heat sinks at the back of the iPad might make it less ergonomic to carry.
Cooling fans – Now this might work. All we need is somewhere to mount the fans, allow the air to move around the back of the iPad and carry the heat off the surface.

FEASIBILITY TEST

Out of the 4 options, I picked the cooling fans since it seemed the most feasible solution. My initial plan was to build a 3D model and run a CFD simulation to test out the concept. But when I started to draft something on SolidWorks, I ended up designing an iPad case which could house two 10mm fans and with channels for directing air across the back of an iPad. Then since I had access to 3D printing, I decided to just build the prototype, get two 10mm fans and ran an actual test with the iPad.

1st prototype with fans

On one of the few sunny days in autumn, I borrowed a 3rd gen iPad and subjected it to some ‘heating’. I turned on the iPad, stuck a thermocouple on it’s back and left it under the sun. It was about 30 deg C that day. Once the thermocouple reading reached 45 deg C, I inserted the iPad into the prototype case and turned on the fans, while leaving it under direct sunlight. The good news was that the temperature dropped by 5 deg only after a minute or two with the fans on. But rate of cooling slowed down after that and it dropped to 34 deg C after 20 minutes. 34 deg C is still quite warm but since this is still under direct sunlight, and it was a 30 deg C day, I would say it was quite effective.

DESIGN IMPROVEMENTS

In my opinion, the concept worked. The design just needs a bit of tweaking. Firstly, I didn’t get the dimensions of the iPad right so the case didn’t really fit that well. Secondly, I picked the wrong fans – they were a little too big and they needed a 12V supply. Thirdly, the fans had to be switched on manually – it would be better if there was a temperature controlled switch.

So I got all those sorted out:

Improved the case design. Even added a slot to mount a wide angle lens for the rear camera.
Found smaller fans that only required 5V power supply.
Also got some help with building a temperature sensor circuit that will switch on the fans when it gets too hot (it’s adjustable via a variable resistor).

NEXT PHASE?

Before I went ahead to build a second prototype, I decided to find out how much it would actually cost to 3D print it (The first prototype I got was given to me in kind). To my surprise, it would cost over $600. It would actually be a hundred dollars cheaper to have the case prototyped using CNC machining. On the other hand, all those electronic components plus the fans would only cost less than $20.

Well, if I was making a few thousand of those cases, I could just design moulds and get those parts extruded which would then bring down the cost of each iPad case. But how many people will actually need a cooling case for their iPad??

Also when I was working of this project (back in April), there was already the 4th gen iPad in the market, which was kind of an improvement. There were still complains of the iPad 4 being too warm, but I was thinking, it wouldn’t be long before Apple came up with a newer model that will totally solve the heat issue. Fast forward to today, out comes the iPad Air with a brand new processor! Apple has also stopped manufacturing the 3rd and 4th generation iPads. That’s probably because they realised they were inferior designs!

IN THE END

Although I didn’t get to mass produce these iPad cooling cases, it was overall a good experience. I realised that I would have to work faster if I wanted to make accessories for tablets or smart phones because a newer and better version is always coming out. Also the cost of commercial 3D printing services is way too high. If I wanted to get 3 prototype cases built, I will be better off buying myself a 3D printer. The cost of thermoplastics for printing doesn’t seem too expensive. Might be cheaper than traditional ink cartridges!

Anyway, thanks for reading, and if you think this iPad cooling case is a good idea and you want to get one, leave me a message!

Wheelchair Rugby: First Paralympic Gold and some Breakthrough Research

Posted on October 10, 2012 by Julian Chua

Photo from the London 2012 website

The Wheelchair Steelers (Australian Wheelchair Rugby team) recently won the much coveted gold medal at the London 2012 Paralympics. The Steelers have been aiming for this gold medal since the 2008 Beijing Paralympic games where they got silver. Over the past 4 years, the coach and team have been working hard to hone their skills, establish training centres and at the same time attract new talent. There has been year round trainings and competitions, international ones such as the 2010 WWRC, and locally, there’s the annual National League, and annual State League in Victoria. Organisations such as the Disability Sport & Recreation have also been promoting the sport through programs and social media to encourage more people to try out the game.

On the research side of things, there has been a couple of studies conducted at the RMIT Sportzedge program with support from some of the Australian wheelchair rugby athletes and coach:

1) Customisation of rugby wheelchairs for performance – The idea of performance based customisation is to maximise the athletes’ comfort and performance through adjusting a few key parameters of the wheelchair design and finding the optimum setup. The main experiments were designed after much research and field tests were done and this was of course coupled with feedback from the athletes and coach. In the end, a platform was developed that allows athletes of the various classifications to systematically customise their individual wheelchair that not only feels good but also helps the athletes perform. For a video on the wheelchair customisation research, check out Channel Ten’s program Scope where it was featured in an episode on Science in Sports.

Ergometer Tests with the Wheelchair Rig

2) Performance & match analysis of wheelchair rugby athletes using inertial sensors – Match analysis of wheelchair rugby was motivated by the fact that the only option available currently is video software analysis, and even though inertial sensors are so commonly used in other able-bodied team sports, it hasn’t been applied in wheelchair sports. The challenge however is to use the kinematic data for activity identification, and not just for measuring speeds and accelerations. The final outcome would be to use the likes of smart phones that are embedded with MEMS sensors and are programmable, mount them on the rugby wheelchairs during competition, and run apps that can determine and track the various activities and performance. Ultimately, this could assist the coach in monitoring the athletes’ performance or even be used for disability classification studies.

Below’s a list of publications that resulted from related work done in the past 3 years. Most of them were presented at the previous ISEA and APCST conferences as well:

Although most of these work were focused on wheelchair rugby, the concepts and platforms developed could potentially be applied to other wheelchair sports for user optimised wheelchair designs and for monitoring activity & performance.

Re-Engineering Labs

Projects