PURPOSE: To improve the precision in an endurance test by automating the test.

CONSTITUTION: A jig fitted to a manipulator of a positional control and force control type is made to engage with a body to be tested of which the attitude can be changed from a first attitude to a second one and from the second attitude to the first one, and a forcible attitude changing operation is given repeatedly by the manipulator. The position of the fore end of the jig during the change of the attitude and/or an external force acting on the jig is monitored, and when the result of monitoring shows a prescribed abnormal tendency, a prescribed processing for return from abnormality which is determined beforehand is executed.