This week our team altered our project to now provide directions along blind-friendly routes to aid the visually impaired. Due to Eshita dropping the class, Zach and I lack the machine learning knowledge to be able to proceed with the prior design.
I will now be focusing on the front-end of our system. I will be using a Raspberry Pi to gather data from a GPS unit to be able to determine the user’s location. The SparkFun GPS-RTK Dead Reckoning pHAT board appears to be a good unit for the project. The unit attaches to an RPi4 through the 40 pin header, and is easily interfaced with I2C. The unit contains a GPS locator, and an IMU to provide more accurate position readings when a loss of GPS signal is encountered. The unit has heading accuracy of within 0.2 degrees, however the unit does not contain a magnetometer. It achieves this by relying on the GPS moving, combined with accelerometer readings. This may be a potential problem for us given that our user may be standing still for a long period of time, and the heading reading will be prone to drift without the user moving in a direction. A solution to this would be to add a secondary board with a magnometer to tell direction, however this may not be necessary will significantly increase complexity of the unit because we would no longer be able to use the PiHAT 40 pin connector for the GPS and we would have connect both boards to the RPi, sharing the header.
I will also be taking commands from the back-end Pi to give directions to the user via audio. I will be using a Text-To-Speech engine to tell the user where to go and give various status updates given from the back-end Pi. The RPi4 comes with a 3.5mm audio jack capable of outputting audio to a wired ear bud which the user will be able to hear the directions from.
I am currently behind schedule given that our team is re-designing the project, however I am very happy about the new direction of the project. In the past day we have been focusing heavily on the project and will continue to do so in order to have a good design done by Sunday for the design review.