Skip to content

cmcollander/ugv

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

This is a ROS package used for an autonomous UGV for research at the University of Texas at Arlington. This package only implements the motor control, /cmd_vel and /odom. For urdf, taranis controller, and lidar, install UDV package as well.

This package works on differential drive robots using a Roboteq motor controller. (Tested on HDC2460 and MDC2460) This package has been tested successfully with ROS Kinetic and Melodic

TODO: At a later date, I will add the configuration file for my motor driver (MDC2460)

ROS Parameters

  • /motor_controller_usb, which Linux device the Roboteq controller is registered as. Default: /dev/ttyACM0
  • /ugv_vel_in_scalar, Default: (PI/3.0)
  • /ugv_vel_out_scalar, Default: (5.30516666)
  • /ugv_odom_scalar, Default: (PI/25200.0)

Please ensure your controller has the following settings:

  • Left wheel connected to motor 1
  • Right wheel connected to motor 2
  • Encoders connected, tested, and set to tuned PID coefficients in closed-loop speed control
  • Encoder ticks per revolution properly calculated through gear ratio and encoder specs
  • Max velocity for each wheel set to 60 RPM
  • Some parameters may need to be tuned and changed based on your build. Trial and error.

Edit ugv.launch to have the correct wheel_separation and wheel_radius for your robot

After wheels respond to correct direction, speed can be adjusted through proper calculation (or trial and error) of /ugv_vel_in_scalar or /ugv_vel_out_scalar

After wheels respond to correct speed, odom can be adjusted through proper calculation (or trial and error, listed below) of /ugv_odom_scalar

My current method for tuning odom (requires a lidar and transform tree):

  • Visualize in Rviz with /odom as global frame.
  • View lidar and transform tree
  • Rotate robot clockwise.
    • If lidar scan rotates to the right: Decrease the /ugv_odom_scalar parameter
    • If lidar scan rotates to the left: Increase the /ugv_odom_scalar parameter
  • When robot is able to rotate N-rotations without rotation of the laser scan, odom is properly tuned (my N=100)

About

No description, website, or topics provided.

Resources

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published