The present invention provides a robotic locomotive device (1) that is capable of driving itself forwards and backwards, anchoring and steering itself whilst inside a tubular structure (200), for example, the human colon, or any structure comprising two opposing walls (202, 204). In this respect, the device is made up of two or three segments (102, 104, 106) covered in an elastic material and driven by an internal actuating mechanism. All of the segments (102, 104, 106) have a concertina configuration that enable a shortening and lengthening motion. As well as contracting and extending in length, at least one of the end segments (102, 106) is capable of bending at an angle away from the longitudinal axis such that it becomes wedged or jammed between the walls (202, 204) of the tubular structure (200). That is, the end segments (102, 106) are capable of both a bending action and a contracting and extending action. The device (1) moves by alternately jamming a segment (102, 104, 106) between the walls (202, 204) of the tubular structure (200), and then contracting or extending the segments (102, 104, 106) to inch the device (1) forward with a more effective locomotive action. As such, the present invention provides a simplified design that is more robust to harsh or unclean environments, whilst still maintaining the level of performance required from such a device.
