How can I get the speed of an object?

[omichel]

How can I get programmatically the linear/angular speed/velocity of an object or robot in Webots?

[omichel]

Webots provides several functions to get the 3D position of a robot or an object: by taking the first derivative of the position you can determine the velocity. There are also some functions that can be used to get the velocity directly:

Get Velocity in Controller Code

To get the angular velocity of a robot (or robot part) in the robot's controller code: add a Gyro node to the robot (or robot part), then use the wb_robot_get_device, wb_gyro_enable and wb_gyro_get_values functions. You will find more information about the Gyro node and functions in the Reference Manual.

Get Velocity in Supervisor

Using the wb_supervisor_node_get_velocity function it is possible to retrieve both the linear and angular velocity of any Solid node. You will find more information about this function in the Reference Manual.

Get Velocity in Physics Plugin Code

In the physics plugin you can use the ODE's dBodyGetLinearVel and dBodyAngularVel functions. These functions return the linear velocity in meters per second, respectively the angular velocity in radians per second. Please find a description of ODE functions here: here.