This paper presents a miniaturized robot for pulling in pull cords in ductwork for analyzing the ductwork and for detection
of the pipe run. The robot consists of an electrical engine with adjustable mechanical power depending on the application.
For prototyping as well as for producing small batch series the polymer housing of the robot is milled or build by rapid
manufacturing, repectively. The design can also be fabricated by injection molding which is suitable for mass production.
Driving is realized by transforming the mechanical power into motion wheels with profiles fitting to the ductwork. These
can be plugged to the drive axle and changed easily. A tension spring is used to presses the robot to the tube wall for a
required preload of the motion wheels.