Construction of the Rover

The modeling was completed based on 50mm square tubing. The mounting bracket for the hub motors was 40mm, so 38mm square tubing was used in the construction of the Rover. Only two hub motors were available for the proof of concept, so two smaller, non-powered wheels were utilized on the front. To protect the motor from overcurrent damage a 10 amp fuse and switch were wired inline with each battery and controller pair. Robot Operation System(ROS)1 is one of the industry standard for robotic software subsystems. It will be used to collect sensor data, calculate path planning and communicate the appropriate velocities to the left and right motor controllers. Simultaneous localization and mapping(SLAM)2 will be used to map out the target environments and the Nvidia TX1 has very efficient computer vision capabilities that will aid in this task. These functionalities are not within the scope of the class so a Wiimote(bluetooth video game controller) will be used to simulate directives to the wheel subsystems. The Wiimote will communicate via bluetooth to a laptop. A ROS node will convert the analog joystick values into an appropriate velocity and direction which will be sent to each wheel via a serial communication bus. Additionally the ROS node will request current, velocity, gains and PWM settings. All of the wheel data will be bundled and sent to the system for instrumentation and data capture for future analysis.

framewheels

FootNotes:

  1. http://www.ros.org/
  2. https://en.wikipedia.org/wiki/Simultaneous_localization_and_mapping