Method of Active Freewheel Control of a Remote-Operated Pipe Crawler Vehicle

• US 20190331284A1
• Filed: 04/26/2018
• Published: 10/31/2019
• Est. Priority Date: 04/26/2018
• Status: Active Grant

• Current Assignee: Deep Trekker Inc. (Halma PLC)
• Original Assignee: Deep Trekker Inc. (Halma PLC)
• Inventors: Phillips, Sean, Koerth, Kyle
• Granted Patent: US 11,054,079 B2
• Time in Patent Office: Days
• CPC Class Codes: F16L 2101/30 Inspecting, measuring or testing
• CPC Class Codes: F16L 55/32 being self-contained
• CPC Class Codes: F16L 55/46 Launching or retrieval of pigs or moles
• CPC Class Codes: F16L 55/48 Indicating the position of the pig or mole in the pipe or conduit
• CPC Class Codes: G05D 1/0011 associated with a remote control arrangement
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• CPC Class Codes: G05D 1/0891 specially adapted for land vehicles

Abstract

A method of active freewheel control (AFW) of a remote-operated pipe crawler vehicle provides a means of retrieving the pipe crawler vehicle after remote visual inspection of a pipe or other passage through a camera assembly on the pipe crawler vehicle. After the vehicle is remotely driven through the pipe to an inspection location, an operator may engage one or more modes to reverse the drive system of the vehicle back to the entry point of the pipe. The AFW system employs an arrangement of integrated sensors and software to intelligently control a simplified drive system that allows the crawler vehicle to assist motion when a tether connecting the vehicle to a control unit is pulled on.

Claims

1. A method of active freewheel control of a remote-operated pipe crawler vehicle comprises the steps of:

(A) providing a pipe crawler unit, wherein the pipe crawler unit comprises a processor and a drive system;

(B) providing a control unit communicably coupled with the pipe crawler unit through a tether cable;

(C) receiving vehicle advancement signals from the control unit through the processor;

(D) operating the drive system in a forward direction according to the vehicle advancement signals;

(E) receiving a return signal from the control unit through the processor;

(F) detecting a tether tension signal between the tether and the pipe crawler unit; and

(G) operating the drive system in a reverse direction opposite the forward direction, if the tether tension signal is detected.

2. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

providing the pipe crawler unit further comprises a steering system; and

operating the drive system and the steering system according to the vehicle advancement signals.

3. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 2,

wherein the vehicle advancement signals comprise drive signals and steering signals;

wherein the drive system is engaged according to the drive signals, and

wherein the steering system is engaged according to the steering signals.

4. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

receiving a ramp mode selection with the processor from the control unit;

operating the drive system in the reverse direction, if the tether tension signal is detected, and if the ramp mode selection is received with the processor; and

ceasing to engage the drive system in the reverse direction, if the tether tension signal ceases to be detected.

5. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

receiving a hold mode selection from the control unit with the processor; and

operating the drive system in the reverse direction at a predetermined return speed, if the tether tension signal is detected, and if the hold mode selection is received.

6. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 5 comprises the steps of:

providing a return proximity tether value; and

operating the drive system in the reverse direction at a reduced speed, if a tether extension value falls below the return proximity tether value, wherein the reduced speed is less than the predetermined return speed.

7. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

providing a tether extension sensor communicably coupled with the processor;

activating the steering system and the drive system according to the vehicle advancement signals;

continually accumulating a tether extension value through the tether extension sensor while the drive system is engaged in the forward direction; and

continually reducing the tether extension value through the tether extension sensor while the drive system is engaged in the reverse direction.

8. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

receiving a stop signal from the control unit through the processor; and

ceasing to operate the drive system, if the stop signal is received.

9. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

providing the pipe crawler unit further comprises a camera assembly;

receiving camera control signals from the control unit through the processor; and

operating the camera assembly according to the camera control signals.

10. The method of active freewheel control of a remote-operated pipe crawler vehicle as claimed in claim 1 comprises the steps of:

providing at least one inertial sensor of the pipe crawler unit and a gravity compensation algorithm;

measuring a roll value and an incline value through the at least one inertial sensor; and

operating the drive system according to the gravity compensation algorithm using the roll value and the incline value through the processor, wherein the roll value and the incline value are inputs to the gravity compensation algorithm.