This past week I completed work on the sensory and motor foundations for the project. I programmed a full inertial orientation tracking system based on the RPI’s connection to the LSM9DS1 IMU and helped in setting up basic motor functionality the rest of which was completed by my project partners.
Working with the LSM9DS1 9-DOF IMU required communicating with the device via I2C using python libraries. Once all the raw data could be processed I implemented a Mahony AHRS filter which combined the data from the three sensors on the breakout I was using. Combing those three readings can give accurate readings for the absolute orientation of the sensor relative to the earth. This will enable the umbrella to understand where it is relative to the sun and the user which is tracked through the camera. I now need to finish up with the assembly manufacturing that will go on the actual umbrella as we move into the final phases of the project.
The verification that will come later is testing the stability and truthfulness of the LSM9DS1 IMU. Its orientation should not only be accurate but be resilient to motor noise and tuned to the local magnetic interference. The bias values which control its ground truth also nee to be tuned and verified.
In terms of the motors as we complete the final assembly the main verification that will be required is testing of the PID of the motor system. If we were to give the motors a specific orientation to turn to which marking to denote where it should be we can measure the error of how far it is away from its desired orientation and as well how long it takes.