#$%^&*AU2016269501A120170720.pdf#####ABSTRACT Apparatus, including a rigid gripper configured to fasten around a cylindrical object. The apparatus further includes a pair of conductors attached to the gripper so 5 as to make contact with one another, while the gripper is fastened around the cylindrical object, at a location along a length of the conductors that varies responsively to a diameter of the cylindrical object. The apparatus also includes a sensing circuit configured to measure an 10 impedance of a current passing through the pair of conductors and to generate an indication of the diameter responsively to the impedance.1/10 LOO (.0 C/) -6 C) 0i C 0D d
