Full Vehicle Testing

The requirement for a full vehicle testing rig is to simulate the damage from both maneuver loads and endurance track excitations. In contrast to axle test rigs where all the loadings can be applied in a closed force loop, complete vehicle simulation also reproduces the complex distributed loadings which are produced by the multiaxial excitations at the tire contact patches and are reacted by the inertia of the vehicle body.

The following types of full vehicle simulators are available:

• Six Degree of Freedom (6DOF) Simulators
• 12 / 14 Channel Simulators
• Long Stroke Simulators
• Truck Simulators
• Center of Gravity Restraint Simulators

Six Degree of Freedom (6DOF) Full Vehicle Testing Rig

Full vehicle testing rigs are available from IST which allow forces to be applied in all six degrees of freedom (6DOF) at each spindle. These are vertical, longitudinal and lateral loads together with braking, steering and camber moments. They are specifically designed to work in conjunction with wheel force transducers which measure forces in all six degrees of freedom.

IST's unique gain scheduling option for Labtronic™ 8800 digital controller allows the vertical actuator to be operated in load control, resulting in exceptionally high levels of correlation of field measured loads with those reproduced in the laboratory.

Select image to enlarge 12 / 14 Channel Simulators

IST has manufactured a wide range of such complete vehicle test simulators. Operating through fixtures, these systems have been developed over many years, including lightweight loading rods, patented ball joints, hydrostatic bearings and restraint systems. These simulators reproduce vertical, lateral, longitudinal and optionally braking forces and can effectively and accurately reproduce the loadings generated by durability test tracks.

Long Stroke Simulators

Select image to enlarge IST is the only manufacturer of proven test rigs that allows braking and cornering maneuver simulation without restraints on the vehicle body. The maneuver loadings are compressed in time to allow them to be reproduced within the ±500 mm stroke of the horizontal actuators. A unique computer-controlled hydraulic clamping system allows the longitudinal actuator to apply either a braking load at the tire contact patch or a pure longitudinal load at the mid point of the wheel.

The test rig produces no erroneous loadings on the body through external mechanical reaction fixtures and produces excellent results for both the body structure and the axle assembly. Connection of an external pump to supply pressure for the vehicle brakes and the use of wheel force transducers to acquire the desired response data on the test track and as transducers for the iterative drive signal generation on the test rig ensures minimal preparation time for tests and maximum utilization of the test rig.

Truck Simulators

A 12-actuator complete vehicle test rig for heavy trucks is available from IST. These compact test rigs apply vertical, longitudinal and lateral loads to each wheel of the vehicle. The compact design operates with inclined actuators working via bellcranks. The actuators are fixed in extremely stiff trestles ensuring resonance free operation and permitting extensive hard piping of the hydraulics.

The vertical actuators are fitted with a hydraulic pre-load system with a battery of accumulators which applies the static load to the axle. This allows the dynamic part of the actuator to be dimensioned for the dynamic loadings only, resulting in a lower oil flow rate requirement and reducing energy costs.

LabSite™ and Labtronic™ are trademarks of Instron and LabSite^® and Labtronic^® are registered trademarks of Instron in Germany.