Week 15 - Fabrication of case + Testing of LoRa

Fabrication of case for circuit mount

The first task on the agenda is to build the cases for each circuit mount. Each circuit mount would be enclosed by the case for protection and for better presentation. A sliding lid can be removed easily to place the circuit mount.

Originally, we had planned to 3D printed the case and drill a hole in the lid for the Lora antenna. However, the time that the 3D printer would have taken is too long and we are currently looking into laser cutting for a more time effective method to building the case, The next available timing for the booking of the laser cutter would not be until 8th February, as such we are putting the fabrication of the case on temporary halt.

Testing of LoRa

With the LoRa circuit done up simulating the Solar car and the chase vehicle as shown at week 13, We finally are able to test it on the road with the help of Mr Kenny and M Chua (and their cars). Simulating the race convoy for the World Solar Challenge, Mr Chua would be driving first ahead as the Solar car sending data while Mr Kenny would be driving behind as the chase vehicle receiving data. 

For the Solar car, we had the Bluno Nano connected with a temperature sensor and Lora for sending of data. Other than the sensor values being sent, random number are also sent to simulate values for the speed and electric current 

The chase vehicle set up consists of the second Lora connected to an Arduino. The Arduino is next connected to a laptop. The PLX DAQ would then display the value received every interval.

This experiment was conducted around Singapore Polytechnic where we drove around the campus for a few rounds, as attached is a clip showing the receiving part for the chase vehicle.

Mr Chua was driving up front with a speed of 40 -60km while Mr Kenny followed with 50-70km. The furthest distance between the two cars we managed to test was 400m driving around the SP campus. Sending and receiving data was consistent even when Mr Chua finished turning round the corner and being out of sight from Mr Kenny's car.

There were issues observed from this experiment, every 10 readings the data would be "incomplete" with missing values. Due to my carelessness, there were instances where the power bank was off and I didn't realise resulting in the halt of data transmission. The data transmission resumed as soon as the power bank is turned back on.