An autonomous mobile robot is designed to take decisions locally: its behavior is therefore not globally determinist but influenced locally as a function of the situation in which it finds itself. The testing of this type of behavior is therefore complex. Moreover, and in cases such as nuclear power plants where safety is all important, it is necessary to check that the 'back-up' software is truly so under all operational conditions. The purpose of this paper is to present possible solutions to assist in testing the ability of a robot to undertake its mission. The methods of qualification, methods for defining trials and new methods applicable to robot trials in a structured or unstructured environment are described. >