|
Conversion Factors for Servo Calculations
Length
| Mass | Moment of Inertia |
Rotation | Force
Torque | Power | Torque
to Inertia Ratio | Torque Gradient
LENGTH
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
cm
|
inches
|
2.540
|
|
cm
|
feet
|
30.48
|
|
inches
|
cm
|
.3937
|
|
inches
|
feet
|
12
|
|
feet
|
cm
|
3.28
x 10-2
|
|
feet
|
inches
|
8.333
x 10-2
|
MASS
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
gm
|
oz
|
28.35
|
|
gm
|
lb
|
453.6
|
|
gm
|
slug
|
1.459
x 10-4
|
|
oz
|
gm
|
3.527
x 10-2
|
|
oz
|
lb
|
16
|
|
oz
|
slug
|
514.7
|
|
lb
|
gm
|
2.205
x 10-3
|
|
lb
|
oz
|
6.250
x 10-2
|
|
lb
|
slug
|
32.17
|
|
*slug
|
gm
|
6.853
x 10-5
|
|
slug
|
oz
|
1.943
x 10-3
|
|
slug
|
lb
|
3.108
x 10-2
|
*1 slug
mass goes at 1 ft/sec2 when acted upon by 1lb force
MOMENT
OF INERTIA
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
gm
cm2
|
oz
in2
|
182.9
|
|
gm
cm2
|
lb
ft2
|
4.214
x 105
|
|
gm
cm2
|
slug
ft2
|
1.356
x 107
|
|
oz
in2
|
gm
cm2
|
5.467
x 10-3
|
|
oz
in2
|
lb
ft2
|
2.304
x 103
|
|
oz
in2
|
slug
ft2
|
7.412
x 104
|
|
lb
ft2
|
gm
cm2
|
2.373
x 10-6
|
|
lb
ft2
|
oz
in2
|
4.340
x 10-4
|
|
lb
ft2
|
slug
ft2
|
32.17
|
|
slug
ft2
|
gm
cm2
|
7.376
x 10-8
|
|
slug
ft2
|
oz
in2
|
1.349
x 10-5
|
|
slug
ft2
|
lb
ft2
|
3.108
x 10-2
|
ROTATION
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
degrees/sec
|
RPM
|
6.
|
|
degrees/sec
|
rad/sec
|
57.30
|
|
RPM
|
degrees/sec
|
.1667
|
|
RPM
|
rad/sec
|
9.549
|
|
rad/sec
|
degrees/sec
|
1.745
x 10-2
|
|
rad/sec
|
RPM
|
.1047
|
FORCE
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
dyne
|
*gm
|
980.7
|
|
dyne
|
oz
|
2.780
x 104
|
|
dyne
|
lb
|
4.448
x 105
|
|
*gm
|
dyne
|
1.020
x 10-3
|
|
oz
|
dyne
|
3.597
x 10-5
|
|
lb
|
dyne
|
2.248
x 10-6
|
*used
as force units
TORQUE
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
dyne
cm
|
gm
cm
|
980.7
|
|
dyne
cm
|
oz
in
|
7.062
x 104
|
|
dyne
cm
|
lb
ft
|
1.356
x 107
|
|
gm
cm
|
dyne
cm
|
1.020
x 10-3
|
|
gm
cm
|
oz
in
|
72.01
|
|
gm
cm
|
lb
ft
|
1.383
x 104
|
|
oz
in
|
dyne
cm
|
1.416
x 10-5
|
|
oz
in
|
gm
cm
|
1.389
x 10-2
|
|
oz
in
|
lb
ft
|
192.0
|
|
lb
ft
|
dyne
cm
|
7.376
x 10-8
|
|
lb
ft
|
gm
cm
|
7.233
x 10-5
|
|
lb
ft
|
oz
in
|
5.28
x 10-3
|
POWER
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
H.P.
|
(oz
in) (deg./sec)
|
1.653
x 10-7
|
|
H.P.
|
(oz
in) (RPM)
|
9.917
x 10-7
|
|
H.P.
|
(#ft)
(deg./sec)
|
3.173
x 10-5
|
|
H.P.
|
(#ft)
(RPM)
|
1.904
x 10-4
|
|
H.P.
|
Watts
|
1.341
x 10-3
|
|
Watts
|
(oz
in) (deg./sec)
|
1.232
x 10-4
|
|
Watts
|
(oz
in) (RPM)
|
7.395
x 10-4
|
|
Watts
|
(#ft)
(deg./sec)
|
2.366
x 10-4
|
|
Watts
|
(#ft)
(RPM)
|
.1420
|
|
Watts
|
H.P.
|
745.7
|
TORQUE
TO INERTIA RATIO
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
rad
/ sec2
|
oz
in / gm cm2
|
7.062
x 104
|
|
rad
/ sec2
|
oz
in / oz in2
|
386.1
|
TORQUE
GRADIENT
|
TO
OBTAIN
|
MULTIPY
NUMBER OF
|
BY
|
|
#ft
/ rad
|
oz
in/degree
|
0.2984
|
|
dyne
cm / rad
|
oz
in/degree
|
4.046
x 106
|
|
