Sometime recently, there was a report of microchip in cricket bats. This is a little thingummy that will sit on the bat handle, Intel makes this, and is expected to revolutionise how cricket shots are shown to the viewers; it is called Batsense. What it will do is record bat speed through a stroke and impact, angle, follow-through, and the time between the lift and hit. Can one imagine how the same technology could be used in badminton racquets? If will most likely made to fit the bottom of racquet handle without much change in handling characteristics. Not only will it be valuable in training, but coaching for proper technique of racquet preparation, one of the key elements!
Umm, isn't the USENSE sensor or the Oliver PLASMA TX5 RDS exactly what you are imagining? These can be bought right now, although the accuracy is questionable.
