google-deepmind/mujoco_menagerie

Franka Emika - Force Ranges

peterdavidfagan opened this issue · 1 comments

Which model is the issue affecting?
Franka Emika Panda.

What is the issue?
I think the force ranges on actuators might be incorrect (or my understanding of the actuator model is incorrect), leading to unrealistic velocities. it looks like some of the values are set to torque limits from the following spec, should these not be set to force limits? Should the actuator output range be defined in terms of max torque?

Update: the following snippet from the docs leads me to believe that force and torque are synonymous for joints:

The joint and tendon transmission types act as expected and correspond to the actuator applying forces or torques to the target object.

In this sense, if I say the torque limit of my arm is xNm, the max force is xN. I guess I was getting confused over the fact that torque measured in Nm can mean different things in terms of force depending on the length being considered. Of course in this case the SI unit measurement where r=1 is considered and the force is simply xN.

Is there any additional context you can provide (e.g., a spec sheet or a URDF to show a value mismatch)?
Franka Emika Spec Sheet
Current Model
Screenshot 2023-11-29 at 12 03 54

@SaeidSamadi

I was being silly I see that all force ranges appear correct and applied across all joints.