System and method to measure force or location on an L-beam

• US 9,360,383 B2
• Filed: 04/04/2013
• Issued: 06/07/2016
• Est. Priority Date: 04/04/2013
• Status: Active Grant

• Current Assignee: NATE J Coleman and Aexius LLC
• Original Assignee: NATE J Coleman and Aexius LLC
• Inventors: Coleman, Nate J., Long, Michael A.
• Primary Examiner(s): Gibson, Randy W
• Application Number:
  US13/857,140
• Publication Number:
  US 20140299389A1
• Time in Patent Office: 1,160 Days
• Field of Search: 177/211, 177/229, 177/238
• US Class Current: 1/1
• CPC Class Codes: G01B 21/16 for measuring distance of clearance between spaced objects
• CPC Class Codes: G01G 19/40 with provisions for indicating, recording, or computing price or other quantities dependent on the weight indicating means for weighing apparatus G01G23/18; recording means for weighing apparatus G01G23/18; computers in general G06
• CPC Class Codes: G01G 3/1404 combined with means to connect the strain gauges on electrical bridges
• CPC Class Codes: G01L 1/2206 Special supports with preselected places to mount the resistance strain gauges; Mounting of supports
• CPC Class Codes: G01L 1/2262 involving simple electrical bridges

Abstract

Force and location sensing systems and methods are disclosed. A method comprises bending a L-beam at an initially unknown location on a force-supporting portion of the L-beam, the L-beam substantially having a tension side and a compression side, measuring a first local stress at a first location on the tension side, measuring a second local stress at a second location on the tension side, measuring a third local stress at a third location on the compression side, and measuring a fourth local stress at a fourth location on the compression side. A weight-sensing storage system capable of tracking removed items is disclosed with a product image captured via a camera, a plurality of sensors on an L-beam, a first signal from the plurality of sensors indicating a first state prior to change of the product image, and a second signal indicating lower strain on the L-beam than the first signal.

Claims

1. A force-sensing and location-sensing method, comprising:

bending a force-receiving portion of an L-beam;

measuring tension-side strain via a first sensor and a second sensor on the tension side of a leg portion;

measuring compression-side strain via a third sensor and a fourth sensor on the compression side of the leg portion;

determining local stress based on the known geometry and the known material; and

resolving an unknown force on the force-receiving portion of the L-beam;

where the first sensor measures local strain;

a first pair of lateral sensors on the leg portion of the L-beam and a second pair of lateral sensors on the leg portion of the L-beam, where the first and second pair of sensors are perpendicular in orientation to the first, second, third, and fourth sensors;

where the first, second, third, and fourth sensors are capable of sensing strain on the leg portion caused in part by an unknown force on the force-receiving portion of the L-beam; and

where an unknown location of an applied force on the force-receiving portion of the L-beam is resolved by measuring tension and compression on the leg portion of the L-beam.

2. the method of claim 1, wherein the L-beam comprises:

a known geometry, and a known material; and

where the leg portion comprises;

a tension side and a compression side.

3. the method of claim 2, where each sensor is a Wheatstone bridge.

4. the method of claim 3, where the unknown force is measured in local units of stress.

5. A stress measurement system to determine force or location on an L-beam, comprising:

a force-receiving portion;

a leg portion comprising a tension side;

a first sensor on a tension side of the leg portion, where the first sensor measures local strain;

a second sensor on a tension side of the leg portion;

a third sensor on a compression side of the leg portion;

a fourth sensor on the compression side of the leg portion;

a first pair of lateral sensors on the leg portion of the L-beam and a second pair of lateral sensors on the leg portion of the L-beam, where the first and second pair of sensors are perpendicular in orientation to the first, second, third, and fourth sensors;

where the first, second, third, and fourth sensors are capable of sensing strain on the leg portion caused in part by an unknown force on the force-receiving portion of the L-beam; and

where an unknown location of an applied force on the force-receiving portion of the L-beam is resolved by measuring tension and compression on the leg portion of the L-beam.