Mastering the rising trot and developing a quiet hand are amongst the challenges faced by a beginner. So the riding simulator, which might otherwise cause amusement, really is quite a good idea. I saw this model in a newspaper article today.
This simulator can replicate walk, trot, canter and, it is claimed, lateral work. It does come with a rather high (approximately $80,000) price tag. Presumably, there are less expensive simulators that can replicate the trot and canter, useful for developing a good seat and hand. With quality rider training priced at $50+ per half hour in Britain, and rather more for "premium" training, an item like this might prove profitable for a busy, well organised riding centre in or near a metropolitan area.
I remember how difficult it was, when learning to ride, to develop balance and position when the longest trot or canter in a straight line was 40 metres down the long side of the riding school. A realistic simulator might have proven useful.
When running the trail riding centre, I met guests who had never trotted or cantered for more than 40 metres at a time. For them, a 25km trail ride was quite an eye-opener.
I would like to see a project in which the forces applied by riders to their horses are measured. Parameters like pressure under the saddle and tension on the reins, at each pace and in different maneuvers (such as jumping). Modern instrumentation ought to permit real-time measurement of a wide range of pressure inputs whilst the horse works. It might prove to be an excellent project for a group of engineering students in the final year of their degree. For part of the work, perhaps an instrumented simulator might be useful, though the movement of the horse's back under the saddle probably means that a real horse will be needed for meaningful results.
This kind of a project might finally answer questions regarding what really goes on beneath traditional and tree-less saddles. It will also be extremely interesting to find out numerically just what a "contact" really is, and how much it varies between riders.