Communications spooler for a mobile robot

• US 8,485,330 B2
• Filed: 10/24/2011
• Issued: 07/16/2013
• Est. Priority Date: 03/26/2003
• Status: Active Grant

• Current Assignee: Flir Detection, Inc. (Teledyne Technologies Incorporated)
• Original Assignee: iRobot Corporation
• Inventors: Pack, Robert Todd, Sawyer, Tyson, Won, Chikyung, More, Grinnell
• Primary Examiner(s): KIM, SANG K
• Application Number:
  US13/279,962
• Publication Number:
  US 20120097783A1
• Time in Patent Office: 631 Days
• Field of Search: 191/12.2 A, 191/12.2 R, 901/1, 89/11.3, 242/419.1
• US Class Current: 191/12.2A
• CPC Class Codes: B65H 75/425 attached to, or forming part of a vehicle, e.g. truck, trailer, vessel
• CPC Class Codes: B65H 75/4484 Electronic arrangements or adaptations for controlling the winding or unwinding process, e.g. with sensors
• CPC Class Codes: B65H 75/4486 Electric motors
• CPC Class Codes: F41H 11/16 Self-propelled mine-clearing vehicles; Mine-clearing devices attachable to vehicles
• CPC Class Codes: F41H 7/005 Unmanned ground vehicles, i.e. robotic, remote controlled or autonomous, mobile platforms carrying equipment for performing a military or police role, e.g. weapon systems or reconnaissance sensors F41H11/16 takes precedence
• CPC Class Codes: F42B 15/04 using wire, e.g. for guiding ground-to-ground rockets
• CPC Class Codes: H02G 11/02 using take-up reel or drum

Abstract

A cable handling system mounted to a mobile robot to dispense and retrieve cable at zero tension includes a cable reel drive and a downstream tension roller drive that includes an idler. As a cable passes through the tension roller drive, position along the length of the cable and/or the cable speed is monitored accurately by a sensor attached to the idler. A system controller in communication with the sensor controls the cable reel drive and the tension roller drive for dispensing and retrieving cable downstream of the tension roller drive.

Claims

1. A method of controlling a length of cable between a cable reel and a tension roller drive in a cable handling system for a mobile robotic platform, the method comprising:

rotating a tension pulley of the tension roller drive to move a dispensed or retracted length of cable;

estimating a stowed length of cable remaining on the cable reel;

computing a length of cable located between the cable reel and the tension roller drive, based at least in part on the dispensed or retracted length of cable and the stowed length of cable; and

rotating the cable reel to adjust the length of cable located between the cable reel and the tension roller drive.

2. The method of claim 1, further comprising:

providing an idler roller in contact with the cable such that a movement of the cable causes a corresponding rotation of the idler roller; and

measuring the dispensed or retracted length of cable based at least in part on the corresponding rotation of the idler roller.

3. The method of claim 1, wherein the estimating step comprises:

monitoring a rotation of the cable reel;

monitoring a rotation of the tension pulley; and

comparing the rotation of the cable reel and the rotation of the tension pulley.

4. The method of claim 3, further comprising maintaining tension on the length of cable located between the cable reel and the tension roller drive.

5. The method of claim 3, wherein the comparing step is based on the ratio of the rotation of the cable reel and the rotation of the tension pulley.

6. The method of claim 3, further comprising scaling the result of the comparing step by a coefficient.

7. The method of claim 6, wherein the coefficient comprises at least one of a cable reel internal diameter, a cable reel hub width, a cable diameter, and a cable packing fraction.

8. The method of claim 4, wherein the computing step comprises:

estimating the length of cable located between the cable reel and the tension roller drive; and

comparing the estimated length of cable with a distance between the cable roller and a predetermined location on the cable reel, wherein the predetermined location is based at least in part on the stowed length of cable.

9. The method of claim 1, further comprising:

measuring the dispensed or retracted length of cable based at least in part on the rotation of the tension pulley.