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The youBot mobile robot is being used to test some kinematic controllers. There is a problem with the base not reaching the maximum speed. A maximum linear velocity of 1.5 is defined in the configuration file.

  type: steered_wheel_base_controller/SteeredWheelBaseController
  base_frame: base_footprint
  linear_speed_limit: 1.5
  linear_acceleration_limit: 2.5
  linear_deceleration_limit: 2.5
  yaw_speed_limit: 3.0
  yaw_acceleration_limit: 3.2
  yaw_deceleration_limit: 3.2

The maximum speed reported by Gazebo for the platform when I test it is 0.47 whereas the commanded linear velocity in x-axis is 2 and the rest is zero.

name: [ground_plane, youbot]
pose:
   ...
twist: 
  - 
    linear: 
      x: 0.0
      y: 0.0
      z: 0.0
    angular: 
      x: 0.0
      y: 0.0
      z: 0.0
  - 
    linear: 
      x: 0.475034689787  <----- current speed in x-axis direciton
      y: -0.00392167360465
      z: -0.0205054274451
    angular: 
      x: 5.50872400881e-06
      y: 0.000846332345603
      z: 7.43291489694e-05

There is no impact from increasing the PID's gains. The controller is a customised one called steerable_wheel_base_controller.cpp in the same package. Any suggestions?

Melodic ROS, Gazebo 9, Ubuntu 18.04.

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  • $\begingroup$ Do you mean steered wheel base controller? I don't see a steerable one anywhere in the project, but I also don't see any others. It looks like there is the option for a variety of joints, and you're also mentioning PID gains, but I don't know how any of your items are configured. How are you publishing the clock? Is sim time set? Is your joint a position-, velocity-, or PID-controlled joint? $\endgroup$
    – Chuck
    Dec 26, 2022 at 0:53
  • $\begingroup$ @Chuck check it in youbot_simulation/youbot_gazebo_control/src. $\endgroup$
    – CroCo
    Dec 26, 2022 at 0:58
  • $\begingroup$ @Chuck I think the controller converts the linear and angular velocities to each omnidiretional wheel's velocity. The command is cmd_vel. In the config file, there are the PID's gains. $\endgroup$
    – CroCo
    Dec 26, 2022 at 1:11

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