IAI America LSA-W21SS - Manual (Page 34)

20
10.2 Example
Let’s select a motor by following the procedure in “Selection Method.”
 Operating conditions
 Applicable model: Large linear servo actuator LSA-W21SS, LSA-W21SM
 Speed:
2.5 m/s
 Acceleration:
29.4 m/s
2
(The deceleration is
assumed to be the same.)
 Travel:
2.5 m
 Slider load:
10 kg
 The actuator moves back and forth over a stroke of 2.5 m.
The above operation pattern can be illustrated
by the graph shown to the right.
Now, let’s start calculation according to “Selection Method.”
Test condition [1], “maximum trust.”
Apply the above operation pattern to the aforementioned equation of maximum thrust.
Here,
M:
Slider weight (10 kg for the large linear servo actuator LSA-W21SS/LSA-W21SM)
m: Slider load (kg) : 10 kg in this example
a: Commanded acceleration (m/s
2 ) : 29.4 m/s 2 in this example
Ff: Traveling resistance (N) : 120 N in this example
From above, Fa is calculated as follows:
Fa = (20 x 29.4 + 120)
 708 N
The calculated value exceeds the maximum thrust 600 N of the large linear servo actuator LSA-
W21SS/LSA-W21SM.
Let’s lower the specified acceleration to 19.6 m/s
2
. Fa changes as follows:
Fa = (20 x 19.6 + 120)
 512 N.
The calculated value is smaller than the maximum thrust 600 N of the large linear servo actuator LSA-
W21SS/LSA-W21SM.
Speed
Time