9
2.4
System Parameters
Table 2.2 lists and characterizes the main parameters associated with the Qube-Servo 3.
Table 2.2: Qube-Servo 3 System Parameters
Symbol Description
Value
V
nom
Nominal input voltage
24.0 V
τ
nom
Nominal torque
20.4 mN-m
ω
nom
Nominal speed
5400 RPM
I
nom
Nominal current
0.5 A
R
m
Terminal resistance
7.5
Ω
k
t
Torque constant
0.0422 N-m/A
k
m
Motor back-EMF constant
0.0422 V/(rad/s)
J
m
Rotor Inertia
1.4×10
−
6
kg-m
2
L
m
Rotor inductance
1.15 mH
m
h
Module attachment hub mass
0.0106 kg
r
h
Module attachment hub radius
0.0111 m
J
h
Module attachment moment of Inertia
0
.
6×10
−
6
kg-m
2
Inertia Disc Module
m
d
Disc mass
0.053 kg
r
d
Disc radius
0.0248 m
Rotary Pendulum Module
m
r
Rotary arm mass
0.095 kg
L
r
Rotary arm length (pivot to end of metal rod) 0.085 m
m
p
Pendulum link mass
0.024 kg
L
p
Pendulum link length
0.129 m
Motor and Pendulum Encoders
Encoder line count
512 lines/rev
Encoder line count in quadrature
2048 lines/rev
Encoder resolution (in quadrature, deg)
0.176 deg/count
Encoder resolution (in quadrature, rad)
0.00307 rad/count
Amplifier
Amplifier type
PWM
Peak Stall Current
1.8A @ 15V
Continuous Sustainable Current
0.58A @ 5V
Output voltage range (recommended)
±10 V
Output voltage range (maximum)
±15 V
Default deadband
0.65V
