Drivven, Inc.
Throttle Driver Module Kit
© Drivven, Inc. 2009
• Throttle Driver Module Kit User’s Manual • D000017 • Rev B
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throttle_rt_control.vi
This VI implements electronic throttle position control at the RT level using three algorithms. The
first algorithm is PID control using two sets of gains. One set of gains is for positions above
ThetaLH and the other set is for positions below ThetaLH. The second control algorithm is to
compensate the output for travel through the vicinity of the ThetaLH position, as there is a change
in spring return force at that position. The third control algorithm is to compensate the output for
stiction which is most effective while positional errors are small. Please refer to the context-help
of the individual tuning parameters, as well as the user manual for tuning hints.
The throttle_rt_control.vi (RT VI) and throttle_rt_data_convert_revx.vi must be placed within a
while loop or timed loop and executed at a recommended rate of 100-200 Hz (5-10 msec period).
This rate provides good throttle control capability. A reference must be opened to a LabVIEW
FPGA application which implements the throttle_revx.vi. Also, FPGA read/write register functions
must be placed within the RT loop to gain access to the ThrottleControl and ThrottleData clusters
of the FPGA throttle_revx.vi.
The values given by the throttle_rt_data_convert_revx.vi may be used for monitoring or control
purposes. If the external analog inputs are used for position control feedback, then they must be
converted to throttle angle by means of a transfer function or lookup table. Drivven provides a
lookup table function in the rt_vi directory provided to all customers. The throttle angle in degrees
should be input to the Theta (deg) input of the throttle_rt_control.vi.
Temperature (C)
The internal temperature of the module in degrees C, as calculated by
the throttle_rt_data_convert_revx.vi.
Battery (V)
The battery voltage supplied to the module, as calculated by the
throttle_rt_data_convert_revx.vi.
ModulePresent
Should be wired directly from the ModulePresent output of the
throttle_rt_data_convert_revx.vi.
ControlEnable
When TRUE, the VI will generate active output values for the
ThrottlePulseWidthTicks output. When FALSE, the VI will write 0 to the
ThrottlePulseWidthTicks output.
ThrottleCalibrations
Collection of calibration parameters for controlling throttle position.
TLead (sec)
Adjusts the lead compensation on the ThetaR value. A lead/lag
compensation function is internally inserted in the ThetaR signal to the internal
PID function. TLead can be increased to intensify the change in ThetaR.
TLag (sec)
Adjusts the lag compensation on the ThetaR value. A lead/lag
compensation function is internally inserted in the ThetaR signal to the internal
PID function. TLag can be increased to slow the change in ThetaR.
KRpos (V/deg)
Proportional gain for the throttle control PID function while Theta
is greater than ThetaLH.
