60
 60 Velocity
 40 ~- WSetpoint

 S 20- Joint 0
 0 Velocity

 o -20 -

 S -40

 -60
 0 60 120 180 240 300 360 420 480
 Time (1/60 sec)

Figure 9.2. Typical closed-loop response of joint 0 to an alternating step input of 39.1 deg/sec,
 joint 2 positioned at its mid location.


 80

y 60

S 40

 20

 0

o -20

0 -40

 -60


Velocity Setpoint


 0 60 120 180 240 300 360
 Time (1/60 sec)

Figure 9.3. Typical closed-loop response of joint 0 to an alternating step input of 48.8 deg/sec,
 joint 2 retracted.


this input value was 26 percent. For joint 0 velocity control, a maximum steady-state velocity

error of 40 percent and a maximum overshoot of 45 percent were specified as the performance

requirements (see chapter 7). The closed-loop response of the system to various magnitude steps