General Information; Steering Input Devices - Danfoss PVED-CLS User Manual

ENGINEERING TOMORROW

General information

As user comfort receives higher and higher focus along with higher demands for automation and safety, new
technologies are necessary to take on this challenge. The new technologies are using electro-hydraulics, combining
hydraulic power with electronics and computer power.
Electro-hydraulic steering system has the advantages over pure hydraulic steering systems such as the ability to meet
specific functionalities on request.
Increasing demand shows a trend for a higher safety-level up to AgPl "d" for off-road driving.
In order to give this functionality Danfoss has developed the PVED-CLS. The PVED-CLS is based on Danfoss PVE
technology, as used in electro hydraulic proportional valves for decades. PVE modules are used with PVG spool valves
and dedicated spool valves for steering applications, OSPE and EHPS as well as the EHi-E and EHi-H systems.
The PVED-CLS is designed according to state-of-the-art standards regarding functional safety, including ISO 13849,
EN 16590 (ISO 25119) and IEC 65108. Dedicated safety functions are integrated that offer suitable risk reduction, when
applied in accordance with Danfoss recommendations.
In combination with the OSPE/EHi-E steering unit the PVED-CLS forms a category 3 architecture according to ISO
13849. Achievable performance level is "d" for electro hydraulic steering, which makes the OSPE/EHi and PVED-CLS
combination suitable for off road application, for instance with typical agricultural vehicles. Actual required
performance level for any particular vehicle should be determined through appropriate hazard and risk assessment.
Important
The OEM is fully responsible for making and documenting their own hazard and risk assessment and can only use the
Danfoss documentation as input for their own hazard and risk assessment.
For more safety related details on OPSE/EHi-E, EHi-H and EHPS, with PVED-CLS, please see the Danfoss document,
PVED-CLS Safety Manual.
1.1

STEERING INPUT DEVICES

The PVED-CLS can utilize a variety of steering input devices:
•
Steering wheel sensor – SASA
•
Auxiliary mini-steering wheel
•
Auxiliary open loop joystick
- CAN based
- Analogue
- Elobau®
•
Auxiliary closed loop joystick
- CAN based
•
ISOBUS curvature commands
Both a SASA and an auxiliary steering device may exist simultaneously on the CAN bus in a steering system, though
only one of the three auxiliary steering devices can be configured per steering system.
For SASA and mini-steering wheel, up to five individual predefined steering programs may be configured for fast-steer,
and made available through the vehicle MMI.
In order to utilize a closed loop joystick a wheel angle sensor must be present in the system.
The PVED-CLS suports ISOBUS 11783 curvature commands (format-option to support GMS message according to
ISO11783-7:2009 or ISO11783-7:2015 by parameter P3326), as well as input from a Danfoss SASA steering wheel
sensor
© Danfoss | August 2018 AQ00000211 | 11