Models & Refined Design

The initial alpha prototype was used as a proof of concept to determine the viability of the differential drive system. The components were created using 3D printer. The main housing was created using aluminum extrusions. This systems used herringbone gears to transmit the motors to the differential drive. A rough control system was also devised for the pan system. Although this prototype proves the functionality of the differential drive, it also shows some key issues that needed to be addressed. For example, the herringbone gears would often skip when chancing direction and the differential arm was unable to support substantial weight.

The issues with the alpha prototype informed changed for the final beta prototype. Instead of herringbone gears, a pulley system was installed instead with a tensioner system to keep the belts taut. The prototype is also utilizing stronger 24V motors compared to the 12V motors used for the alpha. The prototype is codes and powered by an Arduino UNO microcontroller which interfaces with the motor controller and operates the control system via two potentiometers. The tablet used is a Microsoft Surface 3 that is using a Logitech webcam.

The remote size program was created using the official Tobii Eyetracker software development kit for use in Unity. The software utilizes the Tobii Eyetracker 4 and marks the position where the user is looking as a pixel. This information is converted into a desired viewing position both for horizontal and vertical viewing. This displaced position is what is used as input for the PID controller which informs how the motors on the local side should operate.