Curtis 1232E User manual

Manual
for Controller Models
1232E / 34E / 36E / 38E / 39E
and 1232SE / 34SE / 36SE / 38SE
Read Instructions Carefully!
Specications are subject to change without notice.
© 2021 Curtis Instruments, Inc. ® Curtis is a registered trademark of Curtis Instruments, Inc.
© The design and appearance of the products depicted herein are the copyright of Curtis Instruments, Inc. 53097 DD Supplement, Rev A May 2021
Curtis Instruments, Inc.
200 Kisco Avenue
Mt. Kisco, NY 10549
www.curtisinstruments.com
» Software Version OS 37.0 «
DUAL DRIVE OPERATION

Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
pg. ii
TABLE OF CONTENTS
CHAPTERS
1: OVERVIEW ...................................................................................................................................... 1
2: WIRING ........................................................................................................................................... 2
3: PROGRAMMABLE PARAMETERS ..................................................................................................... 5
4: DETERMINING CRITICAL ANGLE AND INNER WHEEL SPEED ............................................................. 9
5: DUAL DRIVE SETUP........................................................................................................................ 12
6: VEHICLE CONTROL LANGUAGE & CAN............................................................................................ 14
7: TROUBLESHOOTING....................................................................................................................... 19
TABLES
TABLE 1: DUAL DRIVE PROGRAM MENUS: 1311/1313 /1314 PROGRAMMER....................................... 5
TABLE 2: DUAL DRIVE TROUBLESHOOTING CHART............................................................................. 21
FIGURES
FIGURE 1: VARIOUS DUAL DRIVE VEHICLE CONFIGURATIONS. .............................................................. 1
FIGURE 2A: WIRING BETWEEN THE MANAGER AND ANCILLARY DUAL DRIVE
TRACTION CONTROLLERS............................................................................................. 2
FIGURE 2B: BASIC WIRING DIAGRAM FOR MANAGER CONTROLLER, DUAL DRIVE OPERATION.............. 3
FIGURE 2C: BASIC WIRING DIAGRAM FOR ANCILLARY CONTROLLER, DUAL DRIVE OPERATION. ........... 4
FIGURE 3: TYPICAL 3-WHEEL DUAL DRIVE VEHICLE GEOMETRY.......................................................... 10
FIGURE 4: TYPICAL ARTICULATED STEERING DUAL DRIVE VEHICLE GEOMETRY................................... 10
FIGURE 5: RATIO OF INNER-WHEEL SPEED TO OUTER-WHEEL SPEED. ............................................... 11
FIGURE 6: INNER-WHEEL AND OUTER-WHEEL SPEED MAPS. ............................................................. 11
FIGURE 7A: MOTOR COMMAND DIAGRAM, MANAGER CONTROLLER. ................................................. 15
FIGURE 7B: MOTOR COMMAND DIAGRAM, ANCILLARY CONTROLLER................................................. 16

1 — OVERVIEW pg. 1
1 — OVERVIEW
e 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 xed-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.
e 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 congurations.
Dual Drive uses dierent speed maps for the two traction motors, one for the inner wheels and one
for the outer wheels. ese 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
congurations.
Three-wheel:
Front-wheel steer:
Rear-wheel steer:
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021

2 — WIRING
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 2
2 — WIRING
One of the two controllers is designated the manager and the other the ancillary. e manager controller
operates the le motor and the ancillary operates the right motor. e throttle and brake inputs go to the
manager. e steering pot input goes to the Pot2 input on the ancillary controller.
A single main contactor is used, and is controlled by the manager. e KSI, CAN H, and CAN L pins of
the two controllers are connected together. B+ from the main contactor and the keyswitch are supplied to
each controller through separate pairs of fuses to enable operation to continue if one side fails. See Figure
2a, below, for an overview of the common wiring between the two controllers, and Figures 2b and 2c for
the detail in each controller.
Figure 2a
Wiring between the manager and ancillary Dual Drive traction controllers.
SWITCH 2 /
ANALOG 2
J1-8
I/O GROUND J1-7
POT2 HIGH J1-27
POT2 WIPER J1-17
POT LOW J1-18
STEERING
POT
RIGHT
AC
MOTOR
J1-5
J1-13 KSI
COIL RETURN
BRAKE
J1-1 KSI
POSITION
FEEDBACK
DEVICE
J1-26
J1-31
J1-32
J1-7
J1-23
J1-35
J1-21
J1-34
Short for 120Ω
CAN bus termination
B+
V
+5V
FEEDBACK B
CAN TERM L
CAN L
U
W
FEEDBACK A
I/O GROUND
CAN TERM H
CAN H
RIGHT MOTOR
TEMP
SENSOR
ANCI L L ARY CO NT RO L L ER
1232E/34E/36E/38E/39E
1232SE/34SE/36SE/38SE
B-
DRIVER 2
SWITCH 8
J1-33
REVERSE
SWITCH 7
J1-22
FORWARD
SWITCH 3
J1-9
INTERLOCK
SWITCH 2 /
ANALOG 2
J1-8
I/O GROUND
J1-7
THROTTLE
POT HIGH
J1-15
THROTTLE
POT WIPER
J1-16
POT2 HIGH
J1-27
POT2 WIPER
J1-17
POT LOW
J1-18
THROTTLE
POT
BRAKE
POT
LEFT
AC
MOTOR
MAIN
J1-5
J1-6
J1-13
DRIVER 2
DRIVER 1
KSI
COIL RETURN
MAIN
BRAKE
J1-1
KSI
J1-26
J1-31
J1-32
J1-7
J1-23
J1-35
J1-21
J1-34
Short for 120ΩΩ
CAN bus termination
BATTERY
(24–80V)
KEYSWITCH
B+
V
+5V
FEEDBACK B
CAN TERM L
CAN L
U
W
FEEDBACK A
I/O GROUND
CAN TERM H
B-
CAN H
LEFT MOTOR
TEMP
SENSOR
EMERGENCY
STOP
MANAGER CONTROLLER
1232E/34E/36E/38E/39E
1232SE/34SE/36SE/38SE
POSITION
FEEDBACK
DEVICE
Note: See the 1239E manual for typical wiring for the external high-voltage
battery precharge circuit and for the 12V KSI and switch/driver I/O.

2 — WIRING pg. 3
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
e manager controller is wired to all the components except those related to the Right motor and
the steering pot.
Figure 2b
Basic wiring diagram for manager controller, Dual Drive operation.
SWITCH 16
J1-14
SWITCH 8
J1-33
REVERSE
SWITCH 7
J1-22
FORWARD
SWITCH 6
J1-12
SWITCH 5
J1-11
SWITCH 4
J1-10
SWITCH 3
J1-9
INTERLOCK
SWITCH 2 /
ANALOG 2
J1-8
J1-24
I/O GROUND
J1-7
THROTTLE
POT HIGH
J1-15
THROTTLE
POT WIPER
J1-16
POT2 HIGH
J1-27
POT2 WIPER
J1-17
POT LOW
J1-18
THROTTLE
POT
BRAK
POT
LEFT
AC
MOTOR
MAIN
J1-2
J1-3
J1-4
J1-5
J1-6
J1-13
PROP. DRIVER
DRIVER 4
DRIVER 3
DRIVER 2
DRIVER 1
KSI
COIL RETURN
MAIN
J1-1
KSI
POSITION
FEEDBACK
DEVICE
J1-26
J1-31
J1-32
J1-7
J1-23
J1-35
J1-21
J1-34
Connect jumper for 120Ω
CAN bus termination
J1-25
J1-28
J1-29
J1-7
SERIAL PORT
(4-pin Molex)
4
3
1
2
CURTIS
MODEL 840
DISPLAY
8
6
5
BATTERY
(24–96V)
KEYSWITCH
B+
V
+5V
POSITION FEEDBACK B
CAN TERM L
CAN L
+12V
RX
I/O GROUND
U
W
POSITION FEEDBACK A
I/O GROUND
CAN TERM H
B-
CAN H
TX
LEFT MOTOR
TEMP
SENSOR
EMERGENCY
STOP
J1-30
J1-10
DIG. DRIVER 6
J1-20
DIG. DRIVER 7
to J1-23 on ancillary controller
to J1-35 on ancillary controller
to KSI (J1-1)on
ancillary controller
to B+ on
ancillary controller
MANAGER CONTROLLER
1232E/34E/36E/38E/39E
1232SE/34SE/36SE/38SE
SWITCH 1 /
ANALOG 1
ANALOG OUT
(0–10V)
to B- on
ancillary controller
Note: KTY sensor shown.
The banded end must be
connected to I/O ground.
EMERG. REV.
BRAKE

2 — WIRING
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 4
e ancillary controller is wired only to the Right motor and its encoder and temperature sensor, the
steering pot, CAN H, CAN L, KSI, B+/B–, and an electromagnetic brake.
Figure 2c
Basic wiring diagram for ancillary controller, Dual Drive operation.
SWITCH 2 /
ANALOG 2
J1-8
I/O GROUND J1-7
POT2 HIGH J1-27
POT2 WIPER J1-17
POT LOW J1-18
STEERING
POT
RIGHT
AC
MOTOR
J1-5
J1-13 KSI
COIL RETURN
BRAKE
J1-1 KSI
J1-26
J1-31
J1-32
J1-7
J1-23
J1-35
J1-21
J1-34
Short for 120Ω
CAN bus termination
J1-25
J1-28
J1-29
J1-7
SERIAL PORT
(4-pin Molex)
4
3
1
2
B+
V
+5V
POSITION FEEDBACK B
CAN TERM L
CAN L
+12V
RX
I/O GROUND
U
W
POSITION FEEDBACK A
I/O GROUND
CAN TERM H
CAN H
TX
RIGHT MOTOR
TEMP
SENSOR
to J1-23 on manager controller
to J1-35 on manager controller
to KSI (J1-1)on manager controller
to B+ on manager controller
ANCILLARY CONTROLLER
1232E/34E/36E/38E/39E
1232SE/34SE/36SE/38SE
SWITCH 16
SWITCH 8
SWITCH 7
SWITCH 6
SWITCH 5
SWITCH 4
SWITCH 3
SWITCH 1 / ANALOG 1
ANALOG OUT (0–10V)
J1-14
J1-33
J1-22
J1-12
J1-10
J1-9
J1-24
J1-30
B-
DRIVER 2
J1-2
J1-3
J1-4
J1-10
J1-20
PROP. DRIVER
DRIVER 4
DRIVER 3
DIGITAL DRIVER 6
DIGITAL DRIVER 7
to B- on manager controller
J1-11
ANALOG OUT
(0–10V)
J1-30
J1-6 DRIVER 1
THROTTLE
POT HIGH
J1-15
THROTTLE
POT WIPER
J1-16
Note: KTY sensor shown.
The banded end must be
connected to I/O ground.
POSITION
FEEDBACK
DEVICE

3 — PROGRAMMABLE PARAMETERS pg. 5
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
3 — PROGRAMMABLE PARAMETERS
e following programmable parameters are used to congure the Dual Drive feature. With only a
very few exceptions, all the parameters on both the manager and the ancillary controller should be
set to the same values.
VCL is not required to operate in Dual Drive mode.
Table 1 Dual Drive Program Menus: 1311/1313 /1314 Programmer
DUAL DRIVE MENU............................ p. 6
— Dual Motor Enable
— Dual Motor Ancillary
— CAN Node ID Other
— Dual Motor CAN Rate
— LOS Max Speed
MANAGER MENU................................ p. 7
— Steer Angle Max (deg)
— Turn Accel Rate
— Critical Angle (deg)
— Max Turn Speed
— Inner Wheel Speed
— Steer Type
— Steer Pot Min
— Steer Pot Zero
— Steer Pot Max
— VCL Steer Enable
ANCILLARY MENU............................... p. 8
— Turn Accel Rate
— Critical Angle (deg)
— Steer Fault Min
— Steer Fault Max
TURN FEEDFORWARD MENU............. p. 8
— Turn Accel Rate
— Turn Kvff
— Turn ff Build Rate
— Turn ff Release Rate
PARAMETER CHANGE FAULTS
Parameters marked [PCF] in the menu charts will set a Parameter Change Fault (code 49) if they are
changed while the motor bridge is enabled (interlock = On). Although the parameter will be changed,
the fault will prevent motor control functions until the fault is cleared by cycling the keyswitch. If
the motor bridge is disabled (interlock = O ), changing these parameters will not cause a fault and
the changes will take eect immediately.

3 — PROGRAMMABLE PARAMETERS
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 6
DUAL DRIVE MENU
PARAMETER ALLOWABLE RANGE DESCRIPTION
Dual Motor Enable
|Dual_Motor_Enable
|OptionBits4 [Bit 2]
0x306D 0x00
On / Off
On / Off
To turn on the Dual Drive feature, set this parameter On in both controllers.
Dual Motor Ancillary
|Dual_Motor_Ancillary
|OptionBits4 [Bit 3]
0x306D 0x00
On / Off
On / Off
Set this parameter Off in the manager controller and On in the
ancillary controller.
CAN Node ID Other
Dual_CAN_Node_ID_Other
0x330F 0x00
1 – 127
1 – 127
The manager and ancillary controllers must have different CAN Node IDs, and
each must know the CAN Node ID of the “other” controller so they can talk to
each other.
Set this parameter to the ancillary controller’s CAN Node ID in the
manager controller, and set it to the manager controller’s CAN Node ID in
the ancillary controller.
Dual Motor CAN Rate
Dual_Motor_CAN_Rate
0x38CF 0x00
16 – 40 ms
4 – 10
Sets the rate at which the CAN heartbeat messages are sent from the Dual
Motor System.
LOS Max Speed
Dual_LOS_Max_Speed
0x38A2 0x00
100 – 10000 rpm
100 – 10000
Denes the maximum speed when a Dual Drive controller is running in LOS
(Limited Operating Strategy) mode.

3 — PROGRAMMABLE PARAMETERS pg. 7
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
DUAL DRIVE MANAGER MENU
PARAMETER ALLOWABLE RANGE DESCRIPTION
Steer Angle Max (deg)
Dual_Steer_Angle_Max
0x38A3 0x00
45 – 90 deg
45 – 90
Set this to the maximum steer angle that is physically possible on the vehicle.
(Steer Angle is the angle-in-degrees that the steer wheel(s) "turn" from their
center/straight-ahead or zero-degree position).
Turn Accel Rate
Dual_Turn_Accel_Rate
0x38A8 0x00
0.1 – 30.0 s
100 – 30000
As the steering angle increases from the edge of the deadband to the
critical angle (Critical Angle), the acceleration rate is reduced linearly from
the normal value to the programmed Turn Accel Rate (see Figure 6). Higher
values represent slower acceleration.
This parameter appears in multiple places. Changing the value of this
parameter affects all parameters listed below:
Program » Dual Drive » Ancillary » Turn Accel Rate
Program » Dual Drive » Turn Feedforward » Turn Accel Rate
Critical Angle (deg)
Dual_Critical_Angle
0x38A6 0x00
45 – 90 deg
45 – 90
Set this parameter to the angle at which the vehicle pivots around its inner
wheel. Use the critical angle equation to determine this value.
This parameter appears in multiple places. Changing the value of this
parameter affects all parameters listed below:
Program » Dual Drive » Ancillary » Critical Angle (deg)
Max Turn Speed
Dual_Max_Turn_Speed
0x38A7 0x00
0 – 100 %
0 – 32767
As the steering angle increases from the edge of the deadband to the
maximum steer angle (Steer Angle Max), maximum speed is reduced
linearly from the normal value to the programmed Max Turn Speed
(see Figure 6).
Inner Wheel Speed
Dual_Inner_Wheel_Speed
0x38A9 0x00
–100.0 – 0.0 %
–32767 – 0
Set this parameter to the Inner wheel speed as a percentage of outer wheel
speed when the steer angle is 90 degrees. Use the inner wheel speed
equation to determine the appropriate percentage.
Steer Type
Dual_Steer_Type
0x38AB 0x00
1 – 5
1 – 5
[PCF]
Set this parameter to the appropriate type for the steering pot.
1. 2-wire rheostat, 5kΩ–0 input
2. Single-ended 3-wire 1kΩ–10kΩ potentiometer, 0–5V voltage source,
or current source
3. 2-wire rheostat, 0–5kΩ input
4. (not applicable)
5. VCL input (VCL_Steer).
NOTE: Do not change this parameter while the controller is powering the
motor. Any time this parameter is changed a Parameter Change Fault (fault
code 49) is set and must be cleared by cycling power; this protects the
controller and the operator.
Steer Pot Min
Dual_Steer_Pot_Min
0x38AC 0x00
0.00 – 6.25 V
0 – 32767
Set Steer Pot Min to the voltage on the steering pot when steering as far as
possible clockwise. Determine the value by reading the voltage on the pot
when steering CW to the maximum position.
Steer Pot Zero
Dual_Steer_Pot_Zero
0x38AD 0x00
0.00 – 6.25 V
0 – 32767
Set Steer Pot Zero to the voltage on the steering pot when steering
straight ahead. Determine the value by reading the voltage on the pot when
steering straight.
Steer Pot Max
Dual_Steer_Pot_Max
0x38AE 0x00
0.00 – 6.25 V
0 – 32767
Set Steer Pot Max to the voltage on the steering pot when steering as far as
possible counterclockwise. Determine the value by reading the voltage on
the pot when steering CCW to the maximum position.
VCL Steer Enable
|VCL_Steer_Enable
|VCL_Steer_Enable_Bit0 [Bit 0]
0x38A5 0x00
On / Off
On / Off
Setting this to On allows VCL to be used for additional steering processing.
Quick Links:
Figure 6 p.11
Equations p.9
– critical angle
– inner wheel speed

3 — PROGRAMMABLE PARAMETERS
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 8
DUAL DRIVE ANCILLARY MENU
PARAMETER ALLOWABLE RANGE DESCRIPTION
Turn Accel Rate
Dual_Turn_Accel_Rate
0x38A8 0x00
0.1 – 30.0 s
100 – 30000
As the steering angle increases from the edge of the deadband to the critical
angle (Critical Angle), the acceleration rate is reduced linearly from the
normal value to the programmed Turn Accel Rate (see Figure 6). Higher values
represent slower acceleration.
This parameter appears in multiple places. Changing the value of this
parameter affects all parameters listed below:
Program » Dual Drive » Manager » Turn Accel Rate
Program » Dual Drive » Turn Feedforward » Turn Accel Rate
Critical Angle (deg)
Dual_Critical_Angle
0x38A6 0x00
45 – 90 deg
45 – 90
Set this parameter to the angle at which the vehicle pivots around its inner
wheel. Use the critical angle equation to determine this value.
This parameter appears in multiple places. Changing the value of this
parameter affects all parameters listed below:
Program » Dual Drive » Manager » Critical Angle (deg)
Steer Fault Min
Dual_Steer_Fault_Min
0x38AF 0x00
0.00 – 5.50 V
0 – 28864
Sets the minimum threshold for the Dual Drive steering pot input. If the
steering pot voltage goes below this threshold, a Dual Severe Fault (75) will
be issued.
Steer Fault Max
Dual_Steer_Fault_Max
0x38B0 0x00
0.00 – 5.50 V
0 – 28864
Sets the minimum threshold for the Dual Drive steering pot input. If the
steering pot voltage goes below this threshold, a Dual Severe Fault (75) will
be issued.
DUAL DRIVE TURN FEEDFORWARD MENU
PARAMETER ALLOWABLE RANGE DESCRIPTION
Turn Accel Rate
Dual_Turn_Accel_Rate
0x38A8 0x00
0.1 – 30.0 s
100 – 30000
As the steering angle increases from the edge of the deadband to the critical
angle (Critical Angle), the acceleration rate is reduced linearly from the
normal value to the programmed Turn Accel Rate (see Figure 6). Higher values
represent slower acceleration.
This parameter appears in multiple places. Changing the value of this
parameter affects all parameters listed below:
Program » Dual Drive » Manager » Turn Accel Rate
Program » Dual Drive » Ancillary » Turn Accel Rate
Turn Kvff
Dual_Turn_Kvff_SpdM
0x38B2 0x00
0 – 500 A
0 – 5000
This parameter can be used to improve the responsiveness of the traction
speed controller to changes in steer angle.
Turn ff Build Rate
Dual_Turn_ff_Build_Rate_SpdM
0x38B3 0x00
0.1 – 5.0 s
100 – 5000
Denes how quickly the Kvff term builds up.
Turn ff Release Rate
Dual_Turn_ff_Build_Rate_SpdM
0x38B4 0x00
0.1 – 2.0 s
100 – 2000
Denes how quickly the Kvff term releases. If the release seems too abupt,
slowing the release rate (i.e., setting this parameter to a higher value) will
soften the feel.
Quick Links:
Figure 6 p.11
Equations p.9
– critical angle
– inner wheel speed

4 — DETERMINING CRITICAL ANGLE AND INNER WHEEL SPEED pg. 9
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
4 — DETERMINING CRITICAL ANGLE
AND INNER WHEEL SPEED
e rst step in setting up the Dual Drive feature is to determine the values of two parameters:
Critical Angle, the angle at which the vehicle pivots with its inner wheel stationary, and Inner Wheel
Speed, the desired inner-wheel speed at a 90° steer angle, expressed as a fraction of the outer-wheel
speed in this condition.*
4-WHEEL APPLICATIONS
Typically the Inner Wheel Speed = 0 for 4-wheel applications, as there should be no counter-rotation
with these vehicles. e Critical Angle is the angle at which the opposite wheels (front le and back
right, or front right and back le) are perpendicular to each other.
3-WHEEL APPLICATIONS
e Critical Angle and Inner Wheel Speed can be determined empirically or calculated using the
following equations, where W=wheelbase, T=track of the driven wheels, and A=distance between the
steered axle and the pivot point (see Figures 3 and 4). For vehicles without a steered axle, use A=0.
Any units can be used (feet, meters, etc.) as long as they are the same for all dimensions.
Critical Angle = 90 – arctan
= Answer in degrees; must be between 45° and 90°.
Inner Wheel Speed =
= Answer in %; must be between –100% and 0.
Example: For T=4, W=6, and A=1,
Critical Angle = 79° and Inner Wheel Speed = -33%.
*If the vehicle has a Steer Angle Max of less than 90°, it still uses the equation presented here
to calculate the proper value for Inner Wheel Speed. Measured inner wheel speed may be
quite dierent from the parameter value setting; this is normal. Use the calculated value as the
parameter setting.

4 — DETERMINING CRITICAL ANGLE AND INNER WHEEL SPEED
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 10
Figure 3
Typical 3-wheel Dual Drive
vehicle geometry.
W
T
T
W
A
Figure 4
Typical articulated steering
Dual Drive vehicle geometry.
W
T
T
W
A

4 — DETERMINING CRITICAL ANGLE AND INNER WHEEL SPEED pg. 11
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
e inner wheel speed is determined by the outer wheel speed, as shown in Figure 5. It decreases
from 100% of the outer wheel speed to zero at the programmed critical angle, and then from zero to
the programmed Inner Wheel Speed value at the maximum steering angle.
Figure 5
Ratio of inner-wheel speed to
outer-wheel speed, assuming a
90° maximum steering angle. 100%
Inner Wheel Speed
0
-100%
10°
90°
Critical Angle
STEERING ANGLE
speed of inner wheel = speed of outer wheel
Speed of inner wheel
Speed of outer wheel
Figure 6
Inner-wheel and outer-wheel
speed maps, assuming full
throttle.
Max Turn Speed
0
10°90°
Critical Angle
100%
-100%
STEERING ANGLE
Steering Angle Max
Inner Wheel Speed
Speed of outer wheel / Max Speed
Speed of inner wheel / Max Speed
e outer wheel speed is derived directly from the throttle request. As a result, the outer wheel speed
decreases linearly with the steering angle as shown in Figure 6.

5 — DUAL DRIVE SETUP
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 12
5 — DUAL DRIVE SETUP
First complete the setup procedures for the two controllers as outlined in the 1232E/34E/36E/38E/39E &
1232SE/34SE/36SE/38SE os37 manuals.. en proceed with these Dual Drive setup procedures.
Before starting the Dual Drive setup procedures, jack the vehicle drive wheels up o the ground so that
they spin freely. Double-check all wiring to ensure it is consistent with the wiring guidelines presented in
Section 2. Make sure all connections are tight.
1 − Installation confirmation
Make sure that the manager controller is connected to the Le motor, and the ancillary controller is
connected to the Right motor.
2 − Programming the manager controller
e easiest method of programming is to set up the manager rst, clone it to the ancillary, and then make
adjustments in the ancillary.
2.1. Set the manager controller’s CAN Node ID in the CAN Interface menu to the manager
controller’s unique ID.
2.2. Adjust the settings of the parameters in the Dual Drive menu:
• Set Dual Motor Enable = On.
• Set Dual Motor Ancillary = O.
• Set CAN Node ID Other = the ancillary controller’s CAN Node ID.
• Set Dual Motor CAN Rate to the desired value.
• Set LOS Max Speed to the desired value.
2.3. Adjust the settings of all the parameters in the Dual Drive Manager menu.
2.4. Set the Interlock Type.
3 − Cloning the manager controller to the ancillary controller
Use the 1313 handheld programmer or the 1314 PC Programming Station for cloning.
4 − Programming the ancillary controller
Aer cloning the manager controller parameter settings to the ancillary controller, the following changes
must be made in the ancillary.
4.1. In the Dual Drive menu, set the ancillary controller’s Dual Motor Ancillary parameter to On.
4.2. In the CAN Interface menu, set the ancillary controller’s CAN Node ID to the ancillary
controller’s unique ID. Remember that this value must be the same as the Manager’s CAN
Node ID Other parameter.
4.3. In the Dual Drive menu, set the ancillary controller’s CAN Node ID Other to the manager
controller’s CAN Node ID.
CAUTION

5 — DUAL DRIVE SETUP pg. 13
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
4.4. Set the Dual Motor CAN Rate parameter to the same value on each controller.
4.5. If the same phase and encoder wiring conventions are used for the manager and ancillary, set
Swap Two Phases and Swap Encoder Direction in the ancillary to values opposite those in the
manager (see Motor menu).
4.6. Adjust the settings of the two parameters in the Dual Drive Ancillary menu as desired.
4.7. Set Interlock Type = 2, because the Ancillary interlock will be arriving over the CANbus.
5 − Setup confirmation
With the vehicle drive wheels still jacked up, apply interlock and throttle and verify that the wheels turn
at the proper speed and direction as the steer angle changes. If either wheel turns in the wrong direction
or appears to be “ghting itself ” (struggling at full current while jerkily turning at very low speed), try
changing the setting of the Swap Encoder Direction or Swap Two Phases parameters. (Refer to setup
procedures in the 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manuals for help resolving encoder
issues.) If the motor still does not respond appropriately, contact a Curtis customer support engineer to
resolve the issues before continuing.
Do not take the vehicle down o the blocks until the motors are responding properly.
CAUTION

6 — VEHICLE CONTROL LANGUAGE & CAN
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 14
6 — VEHICLE CONTROL LANGUAGE & CAN
e motor command diagrams for the Dual Drive controllers are shown in Figure 7a (for the manager
controller, which controls the Le traction motor) and Figure 7b (for the ancillary controller, which
controls the Right traction motor).
Dual Drive operation is initiated by the steer pot, which is connected to the ancillary controller. e steer
pot wiper voltage is sent in a CAN message to the manager controller (Fig. 7a point A) where the wiper
voltage is converted to steer angle. e Steer_Angle and Mapped_rottle are processed and produce a
throttle value for the manager traction controller and the ancillary traction controller (which is sent via a
CAN message to the ancillary controller (Fig. 7b point B).
e throttle processing in the manager controller is similar to the throttle processing in a non-dual-drive
controller except for the additions of steer angle dual throttle processing and sending CAN messages to
the ancillary controller for throttle and brake commands. e brake signal can be followed in the manager
from the brake pot input to the Brake_Command. e Dual_Ancillary_Brake_From_Manager variable is
sent from the manager traction controller to the ancillary traction controller via a CAN message (Fig. 7a
point B to Fig. 7b point B).
e throttle processing in the ancillary controller is dierent from the throttle processing in a non-dual
drive controller because here the manager controller is processing the throttle variables. e Dual_
Ancillary_rottle_From_Manager (Fig. 7b point B) and Dual_Ancillary_Brake_From_Manager (Fig. 7b
point C) arrive from the manager as shown. e rottle Pot input on the ancillary is not used for throttle
and may be programmed in VCL for other uses.
VCL is not required to implement the Dual Drive CAN feature. Meaning that for a system not using
VCL, the dual drive manager/ancillary controllers will operate as described above. However, when
VCL is implemented, should the VCL CAN operation be stop or become idle*, use the VCL function
INIT_DUAL_MOTOR_CAN() to restart (re-initialize) the Dual Drive CAN operation, besides using the
STARTUP_CAN() for VCL CAN.
INIT_DUAL_MOTOR_CAN( )
is function initializes (restarts) the dual drive CAN functions.
Syntax: Init_Dual_Motor_CAN()
Parameters: None.
Returns: None.
Error Codes: None.
*VCL functions that either stop or idle the VCL CAN operation will require re-initializing of the
dual drive CAN. Or, if the CANbus turns OFF or stops.
Examples:
1. e VCL function SETUP_CAN() in a VCL program will "stop" the Dual Drive CAN operation,
because it leaves the VCL CAN system in an idle state.
2. The VCL function SHUTDOWN_CAN () in a VCL program will stop the dual drive CAN
operation, because it stops the VCL CAN system.
3. If the variable can_error_status = 3, the CANbus is O (reference SysInfo, "CAN/Nodes Bus Status
Information" section).
NOTE: When using VCL with Dual Drive, the CAN mailboxes CAN3 – CAN6 are required to be
reserved by the OS for Dual Drive operation. Refer to the "CAN Access IDs" section in the SysInfo le.

6 — VEHICLE CONTROL LANGUAGE & CAN pg. 15
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
X++
Left
Motor
Control
Throttle Type
Reverse Switch
Forward Switch
Throttle Type
Processing
Forward Offset
Throttle Mapping
VCL_Throttle
Throttle_Multiplier
Throttle_Offset
OS Th rottle
Throttle
Type = 5
or
VCL_
Throttle_
Enable = On
Throttle Pot Raw
Forward Max Forward Map Forward Deadband
Reverse Deadband Reverse Max Reverse Map Reverse Offset
Th rottle Command
Control Mode
Processing
Pot2 Raw
+100%
+100%
-100%
Throttle Type<4
and
Forward = Off
and
Reverse = On
and
TMap = 0
Throttle Type <4
and
Forward = On
and
Reverse = Off
and
TMap = 0
U Phase V Phase W Phase
Controller
Torque
Command
Control
Mode
Select = 0 or 1
and
Pump_ Enable
SpdM = On
and
Mapped_
Throttle <0
Throttle_Command
Throttle
TMap
+1
-1
128 1 Brake_Command
Brake Type
Brake Type
Processing
Brake
OS Brake Brake Command
Brake Mapping
VCL_Brake
Brake Type= 5
or
VCL_Brake_
Enable = On
+100%
0%
FullBrake
Brake Max Brake Offset
Brake Map Brake Deadband
0%
Brake Pedal
Enable = On
Control
Mode
Select
= 0, 1, 2
Mapped Th rottle
Mapped Brake
ShutdownThrottle
or
ThrottleInvalid
or
Main Cont.
Not Closed
or
Interlock_State = Off
Steer Angle Max
Steer Angle Mapping
VCL_Steer
OS Steer
VCL Steer
Enable = On
or
Steer Type >3
Steer Type
Steer Pot Min Steer Pot Zero Steer Pot Max
Dual Throttle
Processing
Steer Pot Raw
ShutdownSteer
Dual_Ancillary_Throttle_From_Manager Dual_Manager_Throttle_Command
0°
Steer Angle
Max Turn Speed Critical Angle
Turn Accel Rate
Inner Wheel Speed
Dual Motor
Enable = On
and
Dual Motor
Ancillary = Off
CAN TX
(CAN message
from Ancillary
to Manager)
CAN RX
(CAN message
from Manager
to Ancillary)
CAN RX
(CAN message
from Manager
to Ancillary)
A
B
C
Dual_Ancillary_Brake_from_Manager
Figure 7a Motor command diagram, manager controller.

6 — VEHICLE CONTROL LANGUAGE & CAN
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 16
X++
Right
Motor
Control
Throttle Type
Reverse Switch
Forward Switch
Throttle Type
Processing
Forward Offset
Throttle Mapping
VCL_Throttle
Throttle_Multiplier
Throttle_Offset
OS Throttle
Throttle
Type = 5
or
VCL_
Throttle_
Enable = On
Th rottle Pot R aw
Forward Max Forward Map Forward Deadband
Reverse Deadband Reverse Max Reverse Map Reverse Offset
Throttle Command
Control Mode
Processing
+100%
-100%
Throttle Type<4
and
Forward = Off
and
Reverse = On
and
TMap = 0
Throttle Type<4
and
Forward = On
and
Reverse = Off
and
TMap = 0
U Phase V Phase W Phase
Controller
Torque
Command
Control
Mode
Select = 0 or 1
and
Pump_ Enable_
SpdM = On
and
Mapped_
Throttle <0
Throttle_Command
Throttle
TMap
+1
-1
128 1
Control
Mode
Select
= 0, 1, 2
Mapped Throttle
ShutdownThrottle
or
ThrottleInvalid
or
Main Cont.
Not Closed
or
Interlock_State = Off
Steer Pot Raw
Dual_Ancillary_Throttle_from_Manager
Steer
Angle
Pot
CAN RX
(CAN message
from Manager
to Ancillary)
Dual Motor
Enable = On
and
Dual Motor
Ancillary
= On
CAN TX
(CAN message
from Ancillary
to Manager)
Brake_Command
CAN RX
(CAN message
from Manager
to Ancillary)
Dual_Ancillary_Brake_from_Manager
C
B
A
Figure 7b Motor command diagram, ancillary controller.

6 — VEHICLE CONTROL LANGUAGE & CAN pg. 17
Return to TOC Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021
CAN
The CAN messages indicated by the A, B, and C points in Figures 7a and 7b are shown in the
byte maps below, along with the additional variables that are available (and CAN Index) to Dual
Drive applications.
e manager controller operates the le (side) motor. e ancillary controller operates the right
(side) motor.
e le and right (side) motors are dened as when the vehicle is moving in the forward direction.
PDO3 RX Byte Map (Sent by the manager to the ancillary).
BByte 1 = Dual_Ancillary_Throttle_from_Manager (high byte) 0x38B6 0x00
ancillary throttle command from manager.
B Byte 2 = Dual_Ancillary_Throttle_from_Manager (low byte) 0x38B6 0x00
Byte 3 = Steer_Type_Manager
Steer Type parameter setting from manager;
used to set up proper pot type in the ancillary.
Byte 4 = Flags_Manager_More
Byte 5 = Flags_Manager 0x38BC 0x00
Used to synchronize inputs and outputs between manager
and ancillary.
Byte 6 = Steer_Angle (high byte) 0x38BA
Steer_Angle voltages read on ancillary side, but sent to and
processed on manager side.
Byte 7 = Steer_Angle (low byte) 0x38BA
C Byte 8 = Dual_Ancillary_Brake_from_Manager 0x38B5 0x00
Ancillary brake command from manager.
PDO3 TX Byte Map (Sent by the ancillary to the manager).
A Byte 1 = Current_Ancillary (high byte)
Used to balance the current load between the left and right motors.
A Byte 2 = Current_Ancillary (low byte)
Byte 3 = [Not used]
Byte 4 = Flags_Ancillary_More
Byte 5 = Flags_Ancillary 0x38BD 0x00
Used to synchronize inputs and outputs between manager
and ancillary.
Byte 6 = [Not used]
A Byte 7 = Steer_Pot_Raw (high byte) 0x38BB 0x00
Voltage from steer pot for manager to use in calculating
steer angle.
A Byte 8 = Steer_Pot_Raw (low byte) 0x38BB 0x00
e contents of Flags_Ancillary and Flags_Manager are as follows:
Bit1 = Dual_Motor_Interlock_Bit
Used to synchronize the interlock between the left and
right motors.
Bit2 = Request_Dual_Motor_Interlock_Bit
Used to request the interlock between the left and right motors.
Bit3 = EM_Brake_Ready_To_Set
Used to synchronize the EM brake between the left and
right motors.
Bit4 = LOS_Speed_Flag
Used to initiate LOS speed in the other traction controller.
Bit5 = Main_Sync_Flag
Used to synchronize the Main Contactor states between the left
and right motors.
Bit6 = Main_Closed_Flag
Used to synchronize the Main Contactor “is closed” between the
left and right motors.

6 — VEHICLE CONTROL LANGUAGE & CAN
Curtis 1232E/34E/36E/38E/39E & 1232SE/34SE/36SE/38SE Manual, os37.0 – May 2021 Return to TOC
pg. 18
Bit7 = LOS_Clear_Flag
Used to clear LOS speed in the other traction controller.
Bit8 = Precharge_Sync_Manager_Flag
Used to synchronize the precharge between the left and right
motors.
e contents of Flags_Ancillary_More and Flags_Manager_More are as follows:
Bit5 = Dual_Motor_EM_Brake_Throttle_Flag
Used to synchronize the EM Brake and Throttle between the left
and right motors.
Bit6 = Dual_Motor_Ready_To_Enter_Position_Hold_Flag
Used to synchronize the Position Hold between the left and right
motors.
Bit7 = Dual_Motor_In_Position_Hold_Flag
Used to synchronize Position Hold between the left and right
motors.
Bits 1-4 = [Not used]
Bit8 = Dual_Motor_EM_Brake_Test_Running_Flag.