Inspection robot for horizontal tube inspection having vertically positionable sensor carriage

A method of inspecting horizontal tubes in an industrial environment, comprising:

• positioning a drive module of an inspection robot on a top tube of a plurality of vertically arranged layers of tubes;
• moving a sensor carriage assembly of the inspection robot vertically to align with a selected tube of the plurality of vertically arranged layers of tubes;
• rotating the sensor carriage assembly from a descent position to an inspection position;
• interrogating the selected tube with a sensor of the sensor carriage assembly as the inspection robot travels along a length of the top tube of the plurality of vertically arranged layers of tubes;
• determining a movement of the drive module along the top tube using an encoder including a passive wheel, a spring, and a sliding coupler;
• and
• biasing, using the spring, the passive wheel toward the top tube to ensure contact between the passive wheel and a surface of the top tube.

An inspection apparatus, comprising:

• a drive module comprising a motor and a pair of wheels structured to engage a top tube of a vertically arranged layer of tubes, wherein the motor is operatively coupled to at least one wheel of the pair of wheels;
• at least one telescoping pole;
• a sensor carriage assembly coupled to the at least one telescoping pole;
• a lowering mechanism operationally coupled to the at least one telescoping pole and structured to selectively extend or retract the at least one telescoping pole thereby providing a selected vertical position of the sensor carriage assembly;
• and
• an encoder comprising a passive wheel, a spring, and a sliding coupler, the spring being structured to bias the passive wheel toward the top tube to ensure contact between the passive wheel and a surface of the top tube, the encoder being operatively coupled to at least one of the motor or the pair of wheels and adapted to determine a movement of the drive module along the top tube;
• a controller configured to receive data from the encoder and to determine a location of the drive module along the top tube.