// Robots

Mecanum Drivetrain

I built this drivetrain for the robotics club I founded at DePaul University as a demonstration of the functionality of Mecanum wheels. The frame was constructed using TETRIX extruded aluminum pieces. The wheels were 3D printed using the FormLabs Form 2 Printer. It is autonomously controlled using an Arduino Uno. 

Mecanum wheels are omni-directional wheels that allow a drivetrain to move horizontally, diagonally, and vertically. The two back motors do not have enough torque to move the robot smoothly, and you may notice the assembly swaying unevenly when moving horizontally. The following video is a proof of concept without any control system. 

I created a teleoperated control system for the robot utilizing the ROS (Robot Operating System) framework. An overview of the system is as follows:
 

  • Two Raspberry Pi 3's connected over a WiFi network which utilize ROS. I'm simply sending over float values representing the joystick position over to the second pi on the robot which translates the values into GPIO inputs. 

  • The GPIO inputs are used by the two motor controllers to control the direction of the mecanum wheels. 

© 2019 by Greg Weeks