Highly Miniaturized Robots for Inspection of Small Nuclear Piping

Abstract

Bomb-making in the 20th century resulted in the creation of massive facilities to produce Uranium. These are now defunct, heavily contaminated and facing decommissioning. As part of a multi-billion-dollar agenda, the measurement of radioactivity is required for the safe disposal of residual Uranium in piping. Existing methods involve manual cutting of asbestos-lined thermal enclosures and performing repeated hazardous and inaccurate measurements of radiation from the outside. Manual techniques have proven too approximate, slow and inefficient for this need. Robots, as addressed here, perform accurate, efficient measurement by operating from the inside and viewing the Uranium directly on the interior of the pipe walls.

Carnegie Mellon University has already developed a first-of-kind robot, RadPiper, to address this problem within the largest of these pipes. Development of the large robot had the advantage of big mobility, big batteries, big computing, big sensors and a big radiation detector. The compelling need is the development of a family of such robots for service in the full range of smaller sizes important in these facilities.

This paper describes the development and technical details of a modular robot, NanoPiper, to operate inside the smallest, 3”, piping within these facilities. NanoPiper development has the challenge of constraint to miniaturized mobility, small batteries, small computing, small sensors and a small radiation detector. This miniaturization is so profound that there is a fundamental question of possibility, and success is not foregone. The principles, configuration, and manifestation of such a device are the distinctions of this research.

NanoPiper builds a robust and accurate radioactive model using newly invented acoustic localization, state-of-the-art geometric profiling and miniaturized radiation sensing. Its autonomous robotic in-pipe functionality delivers the precision, repeatability, and certainty unachievable by traditional manual methods.

Creation of NanoPiper is the case proof that the robot for the smallest relevant pipe size is achievable. This exhibits that a family of robot sizes is feasible for all intermediate pipe sizes from those serviced by RadPiper down to those serviced by NanoPiper. The technology is a transformational contribution to the nuclear cleanup industry.