Auto-Steering; Guidance Commands; Calculating The Wheel Angle; Closing The Loop - Danfoss pved-cl Operation Manual

Operation Manual
PVED-CL Controller for Electro-Hydraulic Steering, Version 1.38

Auto-steering

Auto-steering

Guidance Commands

Calculating the Wheel Angle

Symbol
MaxWheelAngleLeft
MaxWheelAngleRight
VehicleLength
ValveType
SteeringType
VehicleLength2
(Only articulated)

Closing the Loop

94 | ©

Danfoss | May 2016

EHPS Type 2 Automatic Steering System Diagram
OSP
OSP
Q
PVE
PVE EHPS Valve
Curvature command EHPS valve
Vehicle speed Position sensor
To facilitate the implementation of the PVED-CL for auto-steering or guidance, it is designed to use
ISO11783 auto-guide messages. This means the PVED-CL can easily be integrated with any GPS, row-
guide, or similar controller sending ISOBUS specific curvature commands.
The messages GuidanceSystemCommand and GuidanceMachineStatus are defined in the PVED-CL
Communication Protocol Technical Information, 11079551.
To position the wheels or the articulation angle correctly some vehicle geometry information is needed.
The parameter values are used by the control algorithm to calculating from Curvature into wheel set-
point (and from wheel set-point to Curvature for generating estimated curvature. The parameters and
shown in the parameter table below.
Other parameters mentioned in this chapter can be used with default values and should only be adjusted
if the performance needs fine-tuning.
Index Default
65099 35 000
65100 35 000
65112 4000
65121 1
65122 1
65123 4000
20 ms
X Set-point
ext
Yact -
Actuator
position
Steering angle sensor
Q Steering
Steering
cylinder
cylinder
Value range
Maximum wheel angle to the left [mdeg].
Measured on the wheel where the wheel angle sensor is mounted.
Maximum wheel angle to the right [mdeg].
Measured on the wheel where the wheel angle sensor is mounted.
Wheelbase from front to rear axle in mm. Articulated vehicle: Distance from front
axle to joint.
1 means EHPS or PVB, 2 means EH.
1 means front wheel steering, 2 means rear wheel steering, 3 means articulated
steering
Only used for articulated vehicles.
Length from joint to rear axle.
Sse, Sts0, Sts1,
Sts2, Sts3, Sts4,
Sts5, Vesm
Port flow Q - Port flow
Kp
limiter
command
20 ms
Ve Vehicle speed
P005 208E
11025583 | AQ00000216en-US0302