Pneumatic impact-drive and tube crawler device for non-destructive inspections

An impact-drive concept is presented for small tube inspection applications. It uses energy transmitted through impacts, in order to move a small device inside pipes of 1" diameter. This device can be connected to an inspection module (camera or ultrasound sensor, for example) and is able to crawl through bends and along many meters with an acceptable speed (minimum 10 mm/s). The impact-drive concept is not new. Some solutions were explored with piezoelectric and electromagnetic actuators. For this prototype, compressed air is used, with a rotating valve controlled with an electrical motor.