Table 1.

z estim, is the estimated height from the vision.

Algorithm for soft dropping
if in force > force threshold or z current < z min
then Drop the object if a contact is detected or the hand has reached a low position
Open the gripper
z speed = z speed
else. Lower the speed command as the hand approaches the estimated contact height
if z current > z estimate + 0.1 then
z speed = z speed ref
else if z current > z estimate + 0.02 then
z speed = z speed ref / 2
else
z speed = z speed ref / 10
end if
end if

z current, is the current height of the robot's hand. z min, is the minimum allowed height, corresponding to the robot's physical limitations. z speed, is the speed command for the robot's hand. z speed ref, is a reference speed given before-hand. in force, is the force read from the wrist's force sensor. force threshold, is a force threshold defined before-hand obstacle detection during the phase where the user steers the robot to ease the control.