This work describes a combine harvester simulator and virtual environment (VE). This interactive and realistic simulator is a novel and unique apparatus used for development and testing of human-machine systems during the design of agricultural vehicles and systems. The combine simulator and VE are being used to develop and evaluate new technologies and automated systems. The simulator provides an innovative testing platform in which to conduct active harvesting experiments that would otherwise be difficult or impossible to perform. The successes of two studies, 'auger spout aiming' and 'combine implement adjust' are described, including experimental results. The novel approach used with this simulator to acquire the voice of the customer can be generalised to the development of other products with a human interface, and applications in other domains are considered.