Finished Assembly and Testing
Firstly, It’s worth mentioning that today I solved the largest issue I had with the network and the product itself. The master device was just receiving too much data from the slaves. It was dropping packets of information and at sometimes rendering the platform unusable. The reasons behind this problem can be found here : Stop Delaying Traffic!.
I coded a way round the problem. This stops the devices sending every data change and only if the sensor changes by more than 2 values (typical jitter amount in the sensor). This means less responsiveness. Thankfully, this was picked up by MAX and I modified the code in MAX to allow for this inconsistency and to update the values accordingly. Whilst not ideal, it’s unlikely this could ever be noticed by the user.Moving forward…
Today I finished assembling all of my devices. This was the first time I was able to test all 8 devices together.
I had a few small parts to print and assemble, the last force sensor for example.
The assembly is very straight forward. I attach a switch to the enclosure then solder the battery into the circuitry and switch lugs. I bring the ‘sandwich’ together and screw fix from the bottom whilst snapping the enclosure into place. This gives solid and flat devices. The battery rests perfectly flat on top of its charger with no for isolation due to the casing of the batteries.
I had 8 solid devices. A celebration in itself.
Here is the initial testing with all 8 devices with all 8 devices.
Password : octaviustesting
A few issues arose during the testing, mostly that some button presses weren’t registering. This issue comes from each slave themselves. I know what is causing this – I’ve boosted the sensitivity too high. This is a simple fix in which I will update on the arduino code tomorrow.
I wish I could update the arduino via the xBee radio. Unfortunately, it means a partial disassembly of each device in order to update them. I have plans for this in the future. The arduino is an excellent prototyping tool, though it has its constraints. A built-in serial USB interface in a small form factor, like what I need for these devices, is one of them.
Another issue was that I found is the devices having difficulty booting up from the battery at times. Even on a full charge I had noticed this behaviour before. This isn’t a huge issue. I can boot them from the power cable, disconnect and then run them from the battery that way.