Apparatus for and method of testing dynamic characteristics of components of vehicle

A dynamic test method for a component of a vehicle, comprising the steps of:

• supporting a dummy chassis with a plurality of actuators connected to a frame;
• supporting the component of the vehicle as an object to be tested, which component includes at least a first wheel, on the dummy chassis;
• calculating forces produced by second wheels other than the first wheel corresponding to the component, and calculating a force generated from the first wheel as an object to be tested, from at least either one of data of reaction on a dummy road surface and data of rotation of the dummy road surface, and calculating a force acting upon the vehicle from a resultant force of these forces generated at the first wheel and the second wheels;
• calculating a load effected at the first wheel;
• and loads effected at the second wheels, with the use of a numerical model of the vehicle;
• driving the actuators so as to apply the thus calculated loads to the first wheel in order to establish a stroke and an alignment of an assembly of the first wheel;
• calculating strokes and alignments of assemblies of the second wheels, with the use of the numerical model of the vehicle;
• and driving the actuators in accordance with the stroke and the alignment of the assembly of the first wheel, which have been established, and the stroke and the alignments of the second wheels other than the first wheel, which have been calculated, so as to adjust an attitude of the dummy chassis to an attitude of the vehicle.

A vehicle component dynamic test apparatus, comprising:

• a frame supported on a base;
• a plurality of actuators connected to said frame, which support a dummy chassis which carries thereon a component of said vehicle to be tested including at least one wheel;
• a dummy road surface simulator supported on the base and having a dummy road surface adapted to simulate a road surface on which the vehicle runs;
• a first control device for the dummy road surface;
• a reaction force measuring element which measures a reaction force produced when the wheel of the component makes contact with the dummy road surface;
• an attitude detecting device comprising displacement detectors provided respectively for each of the actuators, which detects an attitude of the dummy chassis with respect to the frame;
• a second control device for the actuators;
• a numerical model storage device which stores numerical models of the vehicle;
• and
• a computer electrically coupled to said reaction force measuring device, said numerical model storage device, said attitude detecting device and said first and second control devices for computing an attitude of the dummy chassis and a load applied to the road surface from each of wheels of the vehicle, from a measured reaction force delivered from the reaction force measuring device with the use of the numerical models stored in the numerical model storage device, and for delivering instruction signals to the second control device for the actuators and the first control device for the dummy road surface simulator so as to decrease a difference between the attitude of the dummy chassis detected by the attitude detecting device and the computed attitude of the dummy chassis, and to decrease a difference between a load applied to the dummy road surface, which is obtained from the reaction force of the wheel corresponding to the component to be tested, measured by the reaction force measuring device, and the calculated load which would be applied to the road surface by the first wheel corresponding to the component.