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.
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.
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.
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.
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.
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.
