Schematic

Sinusoidal Commutation
Advanced Digital Motor Controller User Manual 101
a 0.1uF ceramic capacitor between the input pin and ground pin on the controller’s
connector
Synchro Resolver Sensor Feedback
Synchro Resolvers are a form of Sine/Cosine sensor based on transformer technology. It is
composed of a fixed primary coil, and two secondary coils that rotate with the rotor. The
two secondaries are 90o from each other. A fixed frequency excitation voltage is fed in the
primary. As the secondary coils turn, and take turn being parallel with the fixed primary,
the voltage amplitude induced in each varies as shown in the figure below.
Fixed Primary
Primary
Rotating
Secondary 1
Sec 1
Sec 2
Rotatiion
Rotating
Secondary 2
Figure 8-9. Resolver equivalent diagram and signals
Controllers models supporting resolvers use one outputs to generate the excitation. The
secondaries are then fed to two analog inputs. Exact wiring depends on the controller
model. Please consult datasheet or contact Roboteq. Resolvers require one time calibra-
tions similar to these for the sin/cos sensors.
Digital Absolute Encoder (SPI) Feedback
Some advanced motors, like these made by Micromotor, incorporate an absolute position
sensor with a high speed serial interface based on the SPI protocol. Controllers supporting
SPI encoders with 12-bit resolution. SPI encoders give the angle’s absolute position. Nev-
ertheless, a calibration of the zero-angle reference must be done once in order to capture
the mechanical offset of the sensor vs the actual 0 degrees position. See “Sinusoidal Ze-
ro-Angle Reference Search Process” on page 104
Sinusoidal Configurations and Calibrations
Sinusoidal mode is selected via the Switching Mode configuration menu in the Roborun
PC utility, or by sending the configuration command:
^BMOD ch 1
Then must be selected the method for capturing the angle of the rotor and the motor
spins. This is done using the Sinusoidal Angle Sensor configuration menu in the utility, or
by sending the command:
^BFBK ch mode
Where mode:
0: Encoder
1: Hall