Mitsubishi Electric 4F-FS001-W200 Instruction Manual page 70

8 Using the Force Sense Function (Programming)
<Force priority mode>
Data from the force sensor is used to control the robot until the force specified with the force specification
・
value is reached.
The robot moves in the direction which satisfies the force specification value by following the axis direction
・
for which force control is specified.
The offset speed for force control is restricted to the speed command value or below.
・
<Speed priority mode>
The robot is controlled so that the speed specified with the speed command value is reached.
・
The robot moves in the direction which satisfies the force specification value by following the axis direction
・
for which force control is specified.
Example: If the robot is moved toward the target object at 1.0 [mm/s] in the -Z direction with a force of 0.5 [N]
until contact is made, and then 1.0 [N] is applied following contact:
• Force command value
• Speed command value
 Mode switching judgment value setting 
If the "force command value" and "mode switching judgment value" are near one another, sensor
noise or vibrations may be generated while pushing with force control at a specified force, resulting
in the possibility that switching between force priroty mode or speed priority mode may occur
unexpectedly. Adjust the judgment threshold to avoid sensor noise or vibrations while referring to
the log data. Alternatively, use the FsGChg command or the FsCTrg command to change the control
features.
• Switching judgment value : (0.0, 0.0, 0.5, 0.0, 0.0, 0.0)
8.1.2.9 Force Sense Control Gain
Force sense control gain is a parameter used to adjust the force sense control responsiveness. The higher the
setting, the higher the force sense control responsiveness, however, increasing the value too much will result in
an ultrasensitive response when contact is made, resulting in unstable operation.
Force sense control gain is affected by the stiffness of the target object, and therefore it is necessary to change
the gain setting value based on the object. Adjust the gain setting valueusing the following method.
<Adjustment method>
1) Set 1.0 as an initial value to adjust the gain setting value to the axis which executes the force sense control.
2) Move the robot at low speed by JOG operation in the axis direction for which force sense control (force
control/stiffness control/limited stiffness control) is enabled until contact is made with the target object.
(speed override: approx. 5%)
3) If the robot rebounds in the opposite direction from the movement direction when contact is made, it is
necessary to lower the gain setting value. (The gain setting value can be increased if the robot does not
rebound.)
<Setting guide>
Target Object stiffness
1.0 N/mm
10.0 N/mm
100.0 N/mm
If the force sense control gain setting is 0.0, offsetting withy force sense control will not be performed. Control
will be the same as normal position control (normal control). Control can be changed from position control to
force control/stiffness control/limited stiffness control or vice versa by changing the gain setting value during
robot movement. (Use the FsGChg command or the FsCTrg command.)
8-58 Force Sense Control
: (0.0, 0.0, 1.0, 0.0, 0.0, 0.0)
: (0.0, 0.0, 1.0, 0.0, 0.0, 0.0)
Force Sense Control Gain
50.0
8.0
1.0