Introduction

This is Blog #4 of my Athlete telemetry design challenge. For background, please read Blog #1, Blog #2 and Blog #3.

If you've been following this so far, you'll know that, despite Christmas coming and going and the onset of Spring, I hadn't received my kit yet. Well guess what? I still haven't received it. I've been promised that it will arrive soon. 

Because I want to finish the project, and this is the last weekend before submission date, I retrieved the RSL10-SENSE-DB-GEVK that I won in last autumn's RoadTest and redeployed it temporarily. In this blog post, I will reveal how I will mount the RSL10-SENSE-DB-GEVK, so I can wear it whilst exercising.

The enclosure

If I had a 3D printer, that would be the obvious solution - I could design and build my own case. Instead, I have been trying various ways of making/repurposing an enclosure for the RSL10-SENSE-DB-GEVK. The best I found was a small, round plastic case for earplugs!

Although that would have worked, it didn't look very cool, and I would still have had the problem of mounting it.

With some "Googling", I found a supplier of IP65 casings (OKW Enclosures) selling an excellent range of enclosures, including a "wearable" range. The "body case" comes in two sizes, and a range of mounting options. The dimensions seemed to be about right, but I got a large and a medium body case for testing purposes. I also obtained a wrist strap and a fastening kit.

When they arrived, I was impressed at the quality of these products. They don't just snap together, as you might expect. The two halves of the casing are held in place by four M2 x 6 mm enclosure screws with a torx T6 head. The two halves are separated by a stylish orange TPV sealing ring which provides additional "cushioning" for the enclosed device. The shape of this sealing ring very conveniently fits around the debug connector on the RSL10-SENSE-DB-GEVK, helping it stay in place.

{gallery} Wrist strap

Testing

Once I had assembled the wrist strap enclosure, it was time for testing. I wanted to test:

• Whether the RSL10-SENSE-DB-GEVK is held in place, without rattling around, whilst running and cycling.
• How well the BLE signal reaches my iPad with my arm moving.
• Whether there are any other issues that might compromise the accuracy of the environmental measurements.

On the first two points, everything seemed fine and the device was very comfortable to wear (Garmin on one wrist, RSL10-SENSE-DB-GEVK on the other).

I left the RSL10-SENSE-DB-GEVK on my wrist for a while and took some measurements inside the house. Then I took it off and noticed this:

Duh! I am skewing the environmental measurements by wearing it next to my wrist (and raising the temperature by around 8 degrees Celsius).

I'm glad I ordered the fixing kit - I removed the wrist strap and substituted the clip.

Then I can wear the device on some part of my clothing that doesn't result in body heat skewing the temperature readings (probably my shoe).

For cycling, I'll just clip it to the bike somewhere. Or maybe on my jacket.

Finishing up

I have almost run out of time for testing but I'll take the RSL10-SENSE-DB-GEVK kit out for a run and for a short cycle ride before submission date in five days' time. I'll be sending the data to the Atmosphere IoT cloud and will download it to my PC alongside the Garmin data for the same activity. I won't have time to integrate it in Golden Cheetah, but I sense that I am almost there.

List of blog posts

Think ON Design Challenge - Athlete telemetry - Blog #1

Think ON Design Challenge - Athlete Telemetry - Blog #2

Think ON Design Challenge - Athlete telemetry - Blog #3

Think ON Design Challenge - Athlete telemetry - Wrap up blog