What are the most significant risks that could jeopardize the success of the
project? How are these risks being managed? What contingency plans are ready?
Currently some of the risks are that we will be unable to connect all 16 intended keys in an efficient and timely manner. This is because if we are unable to increase the limit on the number of keys that can be connected to a single receiver device, it would mean we would have to network multiple receiver devices together to receive all the signals from the individual keys. While this may work for our proof of concept, it would be impractical for an actual, scaled-up keyboard. To manage this risk, we are considering using one of the Seeed BLE boards as the receiver instead, since the nrf52840 can support up to 20 simultaneous BLE connections.
An additional risk is the wireless charging. While the receiver coil is working, the transmitter coil has been giving us issues all week with it either shorting or not outputting a nice sinusoidal signal. To address this, we plan to buy a new transmitter module with a coil that more closely matches the dimensions of the receiver coil and see if that is able to work. If not, then we plan on redesigning the housing slightly to accommodate the slightly longer receiver that comes with the smaller coil.
A change in the receiver microcontroller may be necessary as the Arduino Nano 33 IOT does not seem to be able to support the number of switches we want connected. Additionally, the width of the housing may need to be increased to accommodate the PCB for the wireless charger. Since we already have the BLE boards, no additional cost is borne there. However, we will need to spend an additional 11 dollars on the wireless charger.
The schedule remains the same at this time.
https://ibb.co/S6DHYrk <- Pictures of Coil readings