Increasing robot's speed

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Hi,

This week, I managed to increase the speed of the robot by switching parameters: has_velocity_limits and has_acceleration_limits to true within the joint_limits.yaml file that MoveIt! creates. The speed of the robot's joints can also be increased through this file. The image below shows the default yaml file.

Default joint_limits.yaml

I tested different velocity and acceleration to reduce the duration of the trajectory. I used values of 10, 15 and 20 within max_velocity and max_acceleration which reduced the duration of trajectories from 650ms with the default setting to an average of 350ms. I decided not to increase the speed further as it showed no difference in terms of successfully hitting the puck.

Below are two videos to show the differences of the robot's speed from the default settings to turning off each of the joint's velocity and acceleration.

Limited joint velocities & acceleration


 Customised joint velocities & acceleration

Although increasing the speed of the robot improve the success rate of hitting the puck, there is still a delay which would not be able to handle fast moving pucks. I believe that the delay is transmission of ROS messages to the robot's controller.

In the next blog, I plan on testing the duration when the trajectory prediction takes place compared to the time that the robot actually reaches that point.

Immanuel

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