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### how to get joint torque values in N.m

Hi all,

I am trying to get the current torque/effort values of my revolute joints. I have a JointPtr j1 and I have seen that the method GetForce() it just returns the recent applied force. What I want are the joint efforts. I have seen that I can use the method j1->GetForceTorque() which returns a JointWrench. However, I don't know how to convert the force and torque vectors of the parent and child links of joint j1 to values in N.m (Newtons per meter).

Please any help would be appreciated.

Best regards,

### how to get joint torque values in N.m

Hi all,

I am trying to get the current torque/effort values of my revolute joints. I have a JointPtr j1 and I have seen that the method GetForce() it just returns the recent applied force. What I want are the joint efforts. I have seen that I can use the method j1->GetForceTorque() which returns a JointWrench. However, I don't know how to convert the force and torque vectors of the parent and child links of joint j1 to values in N.m (Newtons per meter).

Edit:

Let's say I want to know the current effort value of joint j1. The parent and child links of joint j1 are parent_j1 and child_j1 respectively.

The force and torque vectors of parent_j1 are F=(fx1,fy1,fz1) and T=(tx1,ty1,tz1) respectively.

The force and torque vectors of children_j1 are F=(fx2,fy2,fz2) and T=(tx2,ty2,tz2) respectively.

In robotics this is called the wrench of a joint. Then, how can I get: Effort/Torque(j1) = .... N.m.

Please any help would be appreciated.

Best regards,