Driving dynamics

Application, homologation, test drives
and tests on test benches:

Our experts deal with
with all facets of driving dynamics.

Using extensive, in-house measurement technology such as steering and braking robots, they carry out approval-relevant and manufacturer-specific tests. As part of the application, they tune the parameters for the electronic control systems as well as for spring, damper and steering systems. With our experts, we are able to supplement the objective measurements with the subjective assessment as well. We assess driving dynamics and ride comfort on the basis of our customers’ driving maneuver catalogs or TRE’s own specifications.

Within the framework of our benchmarks, we compare the products of different manufacturers and develop the basis for optimizing their chassis for our customers.

This enables TRE to take on extensive development tasks in the field of vehicle dynamics and offer its customers a one-stop service.

Driving Maneuvers Catalog (FMK)

At the end of the application, our specialists test the quality of the bedding. To this end, they conduct tests at test sites around the world according to customer-specific or TRE’s own driving maneuver catalogs – directly at the OEM or at a free test site. In this way, we ensure that the application of ESP/ESC, ABS and EPB meets the brand-specific requirements of the vehicle manufacturers.

Homologation

Steering robot

With our steering robots from ABD we perform driving maneuvers for the evaluation of the cornering behavior of vehicles and stability tests for the evaluation and verification of the ESC system (in compliance with the various legal requirements such as FMVSS126, ECE R13H Annex 9a or KMVSS Art.90-2). The tests take place at our customers’ test sites or freely available test sites around the world and form the basis for certifications. Based on the results, we make recommendations for the release of the different systems.

Not only are we proficient in all driving maneuvers, such as the Sine with Dwell, Fishhook and J-Turn, but we also use our own measurement technology to record data: With our OXTS, GPS and inertial navigation system, we can determine the vehicle response very precisely. In this way, we determine exact values with which the cornering and lateral behavior of the vehicles can be precisely evaluated and compared. Our repertoire also includes customized driving maneuvers to determine various driving dynamic variables. They are carried out by trained TRE experts in close coordination with our customers.

TRE experts also have extensive know-how in the use and adaptation of steering robots in motor vehicles. They have not only developed their own connections to the vehicle, but also mastered the handling, programming of driving maneuvers and data evaluation.

Furthermore, customer-specific driving maneuvers to determine various vehicle dynamic variables are also part of our repertoire and are performed by our trained TRE experts in close coordination with the customer.

 

Braking/driving robot

No matter whether Auto Motor und Sport test, ECE-R 13H Annex 9b or other approval-relevant tests: Tests with brake robots from ABD are one of TRE’s specialties. After all, many years ago we were one of the first companies ever to use them for vehicle testing. In the meantime, we have continuously developed the connection to the vehicle and the measurement technology, for example by using GPS and inertial navigation systems. This guarantees precise measured values and good comparability of the results.

With our brake robots from ABD, we can control for pedal travel, pedal force, as well as vehicle deceleration, and adjust brake pressure to within less than one bar. This gives us precise information about braking behavior in different situations – for example, depending on tires or brake pads.

 

Application

Spring damper systems / 7-stamp system

For the application of vertical dynamics, we use a testrig with seven hydraulic rams(7-Post Rig), which can be controlled by both force and displacement. The four wheel rams (125 millimeters amplitude) are responsible for the vertical movement of the wheels, while the three chassis rams (150 millimeters amplitude) contribute the pitch and roll moments as well as the aerodynamic forces. On the test bench, we can examine drivable and non-drivable road vehicles as well as drivable and non-drivable racing vehicles.

With our 7-post rig, we perform modal analysis (e.g., heave, pitch, roll, and torsion excitations) with and without chassis excitations, track simulations with and without chassis excitations, tests to condition virtual vehicle models, and validation tests for simulation models. However, the test rig is also suitable for complete vehicle measurements (e.g. body stiffness and frequency analyses), vertical excitation of aggregate bearings and pre-tuning of derivatives. State-of-the-art test rig technology delivers reproducible results.

TRE also has its own servo-hydraulic damper test bench (100 millimeters amplitude, six meters per second), which we can use to determine shock absorber characteristics and perform release tests. With its help, we check and modify currently installed identifiers, validate defects on the damper and offer our customers a complete service for determining all tuning variants. Our experts can draw on extensive experience with damper systems from various damper manufacturers.

 

Steering systems

When it comes to subjective tuning of steering systems, our many years of experience are of particular benefit to us: our application engineers are very familiar with the influence of the various parameters on driving behavior. In this way, we ensure that the calibration of various steering systems such as EPS, Servotronic or EHPS generates the desired brand-typical driving feel in terms of comfort, straight-line stability, cornering behavior, center position and torque buildup. If it cannot be achieved by purely applicative measures, we develop the necessary changes to the hardware together with our customers.

For objective measurements of temperature effects on steering behavior, we also use tests in the thermal wind tunnel at the customer’s request. There we can thermally measure the steering systems under various boundary conditions in a reproducible manner.

 

Brake control systems

On the road all over the world: Our application engineers test prototypes on our customers’ test sites, on the Nordschleife of the Nürburgring or on the ice of Scandinavian lakes. Thanks to our proximity to motorsport, we have a great deal of experience in the application of chassis systems of all kinds. Our test engineers have excellent skills in assessing vehicle behavior and excel in vehicle control – even at the limits of driving dynamics.

TRE not only takes care of the initial deployment, but also adapts derivatives to the requirements of different markets, for example.

When servicing brake control systems, we find the optimum compromise between driving safety and the driving behavior typical of the brand. We understand the philosophy of our customers, and our applicators ensure that the “DNA” of each manufacturer remains tangible in the chassis. This is done in close coordination with our customers and the system suppliers.

Subjective tuning

Subjective tuning puts the finishing touches on the vehicle at the end of development. In the process, we test and modify all facets of the application worldwide on public roads and under various climatic conditions – including such important vehicle characteristics as spring/damper/stabilizer tuning, elastokinematics, the combination of wheel and tire, and electronic control systems.

Thanks to their long experience, our test drivers have an extremely good feel for each vehicle and thus ensure that a chassis also exhibits the desired brand-typical handling in all vehicle derivatives.

Our experts test and apply the vehicles on proving grounds, race tracks and public roads. TRE test engineers are also trained for testing on the Nordschleife.