Steering test benches

The pinion actuator simulates the forces and displacements acting on the steering . It therefore significantly determines the performance and the possible application of your steering test bench.

Depending on the test cases to be modelled, there may be very different requirements for the pinion actuators and their control. For example, a high degree of synchronization at very low speeds is essential for meaningful friction force measurements on the steering gear, while dynamic drives are required for simulating driving maneuvers or determining the dynamic properties of the steering. High forces and speeds are required for availability measurements, the determination of efficiency or park tests. In turn, high dynamic and highly accurate drives with minimal latency are required for the evaluation of steering characteristics by test drivers in interaction with test benches. The selection and design of suitable actuators is therefore generally more challenging the more flexible the steering test bench is to be used.

The selection of a suitable actuator, its specification and the design of the control system is therefore model-based for the test cases to be mapped and takes into account the properties of all relevant test specimens. In addition to your specific requirements for force, speed, control accuracy, dynamic, latency and synchronization, we naturally also take into account the investment and operating costs.

We are not bound by any operating principle. Quite the opposite: our aim is to offer you the technically and economically best actuators for your specific requirements. The spectrum ranges from spindle drives in test benches with low dynamic requirements to servo-hydraulic drives in endurance test benches and high-performance electric linear drives in high-performance steering test benches, which are used for a wide variety of testing tasks.

The steering robot consists of a electric machine, a precise torque measuring flange and a rigid frame to mount the steering column. A hands-off clutch can optionally be integrated between the steering actuator and the steering spindle for specific automated driving functions.

The desired steering movements and torques are set via the steering machine. We use high dynamic and precise servo machines for this purpose, which can be operated in angle or torque control.

The frame can be designed for seven degrees of freedom with generously dimensioned adjustment ranges so that different test specimens can be tested in their vehicle position. Adjustment is carried out without tool needed in few simple steps. In our hybrid test benches, the steering robot can be replaced by a driver-in-the-loop simulator.

On the road tests are time consuming, expensive and not reproducible. We therefore offer you the option of high quality driver cockpits for our high-performance steering test benches, so that your test bench can be used as a driver-in-the-loop test bench. This allows your test drivers to test the steering characteristics in the virtual vehicle and directly perceive the performance of the steering haptically. Conversion from operation with a steering robot to operation with a driving simulator is quick and easy thanks to our innovative set-up concept, allowing you to switch between the two operating modes at any time.

An example: You use your steering system test bench during the day as a steering-in-the-loop test bench for the characterization of the steering system by a test driver and at night for highly automated function tests. For you, this means less time with reproducible results and high utilization of the test stand.

Our driver simulators also have various set-up axles that can be adjusted without tools so that test specimens of a wide range of vehicle classes can be tested in vehicle position.

For the interior design of your driving simulator, we are happy to use real parts provided by you, such as dashboards, consoles and seats.

During conceptualizing and designing of the mechanical structure of your steering test bench, we put great importance in

• high rigidity
• favorable inherent behavior of the structure
• low maintenance requirements
• large set-up areas
• simple, fast and ergonomic set-up
• consideration of the conditions and constraints at the intended installation site.

Of course, we offer you suitable and fully integrated solutions for the temperature control or air conditioning of your steering gear and/or hand-wheel actuator.

We also offer automated systems for the introduction of salt spray, corrosive water, mud and dust to identify weak points and long-term corrosion effects on steering gears and steering spindles.

Solutions from various manufacturers have become established for residual bus simulation and communication with the test object. We integrate your preferred hardware and software solutions into your steering test bench, ensuring that you can continue to use your established processes and toolchains. This allows you to use synergies and deploy your personnel flexibly.

The on-board battery simulation is used for the electrical power supply of the test object. In the simplest case, this module comprises a recuperating power supply unit, monitored power contactors for the automated switching of the terminals and measurement technology for recording the currents and voltages.

There are also various expansion options. Examples include a redundant on-board power supply simulation with two separate bidirectional power supply units, highly dynamic power supply units, an additional logic supply or the integration of SuperCaps for voltage stabilisation for dynamic load cases. Other options include a connection option for external battery simulators or power supply units, measurement technology extended to include quiescent current measurement or relay isolating adapters for highly automated simulation of electrical faults.

Measurement technology is another key component of a steering test bench. Depending on your requirements and wishes, our measurement technology team will develop various implementation options if necessary and discuss the advantages and disadvantages, existing conflicts of interest and expansion options with you. Here too, we are not tied to any particular supplier, so that we can work with you to develop and implement the solution that best suits your requirements and boundary conditions.

We offer you customized software and hardware solutions for your steering test bench - tailored to your individual tasks and requirements. When designing suitable system and function architectures, we naturally take your existing automation solutions, processes, and toolchains into account in addition to your standards, preferred lists and equipment regulations. If necessary, we implement customized interfaces, e.g. for the integration of additional peripheral devices, communication with higher-level automation systems or for the integration of the test environment into your database systems.