Question for the hand/gripper control about abr_control HOT 2 OPEN

We used to have some examples of the jaco2, but looking at the latest code it looks like its no longer there. However, it's fairly simple to add. The control signal we send, u, can be 9D for the jaco2. You can calculate the first 6 with one of our controllers. The last 3 are the force commands for the 3 fingers of the jaco2. You can change these values to open and close the hand, but we provide no gripper controllers in the repo. Note that if you are planning on using the real jaco2 that the gripper is position based only, but in our mujoco sims they are force based like the other actuators in the arm.

To use this feature just set the use_joint_dyn_addrs to False in the mujoco interface function call send_forces. You can see the docstring here. Then you just add the three force commands you want for the gripper.

from abr_control.

Here is a simple example that oscillates between 4 and -4 Newtons of force every 2 seconds. If you remove the current call to send_forces(... and add this snippet instead:

        period = 2000 # dt is 1ms, making the period 2sec
        max_N = 4 # max number of newtons of force (I believe the units will be Newtons)
        u_gripper = max_N*np.ones(3) * np.sin(count/period * 2* np.pi)
        print(u_gripper)
        u = np.hstack((u, u_gripper))

You can create a controller, or just add a constant force for a set length of time to perform open/close commands given some set of conditions (i.e. if at location X send close command, if at location Y send open command).

from abr_control.