1—OVERVIEW
pg. 1
1—OVERVIEW
The Dual Drive feature of Curtis 1232E/SE, 1234E/SE, 1236E/SE, 1238E/SE, and 1239E controllers
allows two controllers to work together in vehicles with dual fixed-axle drive motors, a steered wheel
or axle, and an analog steer-angle sensor.
The two controllers must be the same size—for example, two 1234E-23XX controllers or two
1239E-65XX controllers. Non “E” controllers cannot be combined with “E” controllers.
The pair of controllers control motor speed on the inner and outer wheels during turns, as well as
vehicle speed and acceleration while turning. Current is automatically balanced between the two
traction motors when driving straight, and a limited operating strategy (LOS) allows limp-home in
case of a steer angle sensor or single motor or controller failure.
Figure 1 shows three typical Dual Drive vehicle configurations.
Dual Drive uses different speed maps for the two traction motors, one for the inner wheels and one
for the outer wheels. These maps modify the throttle requests when the steering angle is outside the
10° deadband. Both are symmetrical around steer angle = 0°.
Figure 1
Various Dual
Drive vehicle
configurations.
Three-wheel:
Front-wheel steer:
Rear-wheel steer:
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os 31 – May 2017
