Steering column testing
Test benches for dynamic testing of steering column
The testing of steering columns is achieved by a rotation of the steering wheel to a certain angle while the other end of the column is hold with a corresponding force. To perform these tests, two electric actuators are required. The first one is to control the angle of the steering wheel. The second one (steering gear side) is synchronized with the first one but is clamped to the column with a define function for the holding force: Md= f(j).
To investigate the wearing of the steering shaft, it is possible to change the clamping point on the column during the test with a translation movement oscillating at a frequency up to 10 Hz.
The test rigs are equipped with angular, moment, distance and displacement sensors.
To suit a variety of steering shaft geometry, the test benches can run in different adjustable axes. For application limited to only a certain type of steering columns, the design is adapted in order to facilitate the setup of the parts.
Operation, parameters of the tests, online graphics and documentation of the tests are controlled by DYNA-MESS testing software CIMTronic Control 2000.
Test machines for timing belts/gears
Dynamic testing of timing belts and gears for service life investigation
The test machine is designed to perform tests on two belts simultaneously. Speed and torque can be adjusted independently for each belt to be tested. The following features are possible with this machine:
- Data recording of fatigue tests
- Pulsed testing with a fixed drive
- Endurance tests with a define load profile
Test modules for various test applications:
- The fixed drive can apply a torque with a frequency up to 10 Hz.
- The drive can apply torque to follow previously recorded vehicle data. The actuator then switches to the appropriate control (angle or torque).
Temperature control is also possible during the test from -50°C up to 125°C.
The following parameters can be measured: belt pretension, torque, angle and the temperature of the belt. All sensors, except the belt temperature sensors, are located outside the test cabinet.
Technical data
| Drive speed: | 0 to 3.000 min-1 |
| Max. torque : |
25 Nm (static) |
| Max. frequency: | 10 Hz |
| Angular displacement: | ± 5 ° |
Pedals and pedal assemblies testing
To perform tests on pedals assemblies, DYNA-MESS uses servo-pneumatic actuators. In addition to the fatigue test to be performed, testing machines by DYNA-MESS allow to evaluated other characteristics like the reliability of the bearings, cylinders, springs, etc.
Pedal operation
The pedals assembly, during the fatigue test, is subjected to a force and displacement control. After moving the pedal to the desired position, the servo-pneumatic actuator switches to force control to apply a user-defined force on the pedal. DYNA-MESS software allows the user to set all these parameters as position, force and loading frequency.
Counterforce simulation
The generation of counterforce acting on the pedal system (brake or clutch force) is also possible by installing another servo-pneumatic actuator. The desired reaction force curve can be defined by the user as a function of the pedal travel. Thus, the control loops for the pedal actuator and the counterforce actuator are linked by a functional relation.
Blocking test
In this case the pedal lever is blocked into a position and a cyclic load with a frequency of 5 Hz is applied. This test can be used to determine the fatigue strength of the pedal lever.
Environmental simulation
DYNA-MESS testing machines can also handle temperature control by using a special cabinet. The temperature during the test can be varied from -40°C up to 80°C.
Test inside the vehicle
Servo-pneumatic actuators can be used to perform test inside the vehicle. With this method, it is possible to reproduce more accurately the normal use of the pedal assembly. Everything can be tested like brakes and clutch system as well as the pedal assembly on the chassis of the vehicle.
Rubber/metal components
Steering wheel testing
DYNA-MESS offers machines to perform fatigue tests on steering wheels. In most cases the steering wheel is fixed by the central hub and the load is applied on the outside rim.
Fatigue test
For fatigue tests, the load can be applied in the following directions on the steering wheel:
- axial
- tangential
The oscillating frequency is between 1 to 10 Hz and the force is generally lower than 1 kN. The steering wheel can be analyzed for any visible damages, cracks or permanent deformations.
For that kind of tests, DYNA-MESS uses its TP 1 LCF servo-pneumatic actuator.
Permanent deformation
The evaluation of the deformation of the steering wheel under load is possible by measuring the variation of the position of one point before and after the load application.
DYNA-MESS use servo-pneumatic actuators to perform those tests. The testing software provided with the machine offers the possibility to change the position where the load is applied without unclamping the steering wheel. This means that it is possible to:
- Measure the load and deformation in more than one place without dismounting the part
- Perform automated tests to determine the deformation of the steering wheel as a function of the load.
Multiaxial loading
Complex loads can be applied with the test rigs equipped with multiple test cylinders. A standard multiaxial test rig consist of a torsion actuator and multiple linear actuators. With that, it is possible to combine bending and torsion stress on the same test rig.
DYNA-MESS testing software ensures an exact compliance to the set values and a perfect phasing of all the individual actuators.
Torsion tests
In addition to the experiment that use linear actuators, torsion tests can be performed with special torsion drives.
In that case, the steering wheel is fixed by the outside rim and a torsion load is applied to the central hub.
Just as the fatigue test, the following parameters can be evaluated: cracks, visible damages and permanent deformation.
Depending on the test to be performed, DYNA-MESS torsion test machines are equipped with servo-pneumatic or servo-hydraulic actuators.
