Optical grid enhancement for improved motor location

Patent metadata

Field	Value
Publication number	US-9465968-B2
Application number	US-201514640504-A
Country	US
Kind code	B2
Filing date	Mar 6, 2015
Priority date	Sep 15, 2011
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

Methods for performing a scheme that results in a refined measurement pattern within an optical grid are provided. Physically adjusting spacing of elements within an optical grid to achieve enhanced resolution is historically unfeasible, as reduction of the spacing causes light sensors of the optical grid to pick up false signals when reading light beams. Technology introduced by the present invention generates a virtual reduced spacing of the elements within the optical grid by using two signals that are slightly different. These slightly different signals can accomplish, at least, quarter-grid spacing resolution within the optical grid. Additionally, the enhanced resolution derived from the virtual reduced spacing is employed to govern movement of a motor. The motor movement is in response to one or more changes of direction such that the motor is operating in its linear range. Advantageously, the virtual reduced spacing allows for substantial movement in a non-linear phase, while only limited movement in a linear phase is necessary to locate accurately a target within the optical grid.

First claim

The invention claimed is:

1. A non-transitory computer-readable storage medium having computer-useable instructions embodied thereon for performing a method, the method comprising:
virtually reducing spacing within an optical grid, wherein the virtually reducing of the spacing within the optical grid is comprised of:
detecting wavelengths of light emitted from at least a single light source impinging upon the optical grid, wherein the detecting of the wavelengths is comprised of receiving input from a first beam of light by reading the first beam of light using a first sensor and a second sensor, wherein the first sensor is spatially offset from the second sensor, and
based on the input, deriving a pattern of transitions as a function of the spatial offset between the first sensor and the second sensor, wherein the pattern of transitions includes one or more transitions that correspond with one or more visual elements, respectively, of the optical grid; and

recording the pattern of transitions in association with clock cycles that are stored against the one or more transitions therein.

2. The computer-readable storage media of claim 1 , wherein deriving the pattern of transitions comprises measuring when a signal curve of the first-beam wavelength produces a high signal.

3. The computer-readable storage media of claim 2 , wherein deriving the pattern of transitions comprises measuring when a signal curve of a second-beam wavelength produces a high signal.

4. The computer-readable storage media of claim 3 , wherein deriving the pattern of transitions comprises applying an algorithm to the signal-curve measurements to identify a transition when either the first-beam wavelength or the second-beam wavelength exclusively produces the high signal.

5. The computer-readable storage media of claim 1 , wherein the components of the optical grid comprise a first light source for emitting the first beam of light.

6. The computer-readable storage media of claim 5 , wherein the components of the optical grid comprise a second light source for emitting a second beam of light.

7. A non-transitory computer-readable storage media having computer-useable instructions embodied thereon for performing a method of virtually reducing spacing of components within an optical grid by detecting wavelengths of light impinging upon the optical grid, the method comprising:
receiving input from a first beam of light emitted from a first light source by reading at least one sensor;
receiving input from a second beam of light emitted from a second light source by reading the at least one sensor, wherein the first beam is offset from the second beam;
based on the inputs, deriving a pattern of transitions as a function of the offset between the first beam and the second beam, wherein the pattern of transitions includes one or more transitions that correspond with one or more visual elements, respectively, of the optical grid, and wherein the pattern of transitions is derived upon the first beam of light and the second beam of light emitted from the first and second light sources, respectively, being refracted from the visual elements of the optical grid and being received by the at least one light sensor; and
recording the pattern of transitions in association with clock cycles that are stored against the one or more transitions therein.

8. The computer-readable storage media of claim 7 , wherein a signal curve of the first-beam wavelength and a signal curve the second-beam wavelength are out-of-phase.

9. A computerized method for utilizing a motor to locate a target between visual elements of an optical grid, the method comprising:
accessing a pattern of transitions derived from measuring one or more beams refracted from the optical grid;
calibrating the motor by counting clock cycles of spacing that separate adjacent transitions within the pattern of transitions;
using the pattern of transitions to advance the motor in a forward direction at a first rate;
upon reaching the target, stopping the motor and counting clock cycles between the target and a transition, within the pattern of transitions, immediately before the target;
operating the motor in a reverse direction until the target and the transition immediately before the target are passed; and
using the counted clock cycles to advance the motor from the transition immediately before the target in the forward direction at a second rate to locate the target.

10. The computerized method of claim 9 , comprising identifying the target is encountered when moving the motor in the forward direction.

11. The computerized method of claim 10 , comprising recording the clock cycles that elapsed between passing a transition immediately before the target and encountering the target.

12. The computerized method of claim 11 , wherein locating comprises beginning forward movement of the motor from the transition immediately before the target while counting down the recorded clock cycles.

13. The computerized method of claim 12 , wherein locating comprises stopping movement of the motor upon completion of counting down the recorded clock cycles, wherein a position of the motor upon stopping corresponds with a location of the target on a barcode.

14. A computer system for performing a method of locating a target on a substrate, the computer system comprising a processor coupled to a computer-readable storage medium, the computer-readable storage medium having stored thereon a plurality of computer-software components executable by the processor, the computer software components comprising:
a resolution component that receives inputs from a light sensor provided within an optical grid, wherein the inputs indicate a beam of light refracting off the substrate and meeting the light sensor;
a processing component that performs an exclusive-or operation using the inputs received by the resolution component and that generates a pattern of transitions from results of the exclusive-or operation;
a characterization component that calibrates a motor, wherein the motor calibration determines a first operating region and a second operating region of the motor, and wherein the motor is configured to move the substrate forward or rearward with respect to the optical grid; and
a communication component that interacts with the motor to locate the target using the pattern of transitions, wherein locating the target comprises:
(a) identifying a particular transition within the pattern of transitions that exists a number of clock cycles before the target;
(b) counting down the number of clock cycles while the motor is moving the substrate within the second operating region from the particular transition toward the target; and
(c) instructing the motor to stop movement of the substrate upon the clock cycles being counted down, wherein the light sensor is substantially aligned with the target upon stopping the motor.

15. The computer system of claim 14 , wherein at least one beam of light is emitted from a light source provided within the optical grid.

16. The computer system of claim 15 , wherein beams of light are emitted with similar wavelengths, while a timing of the beams of light is offset such that the wavelengths are out of phase.

17. The computer system of claim 16 , wherein the beams of light include a first beam of light and a second beam of light that includes a second-beam wavelength that is out of phase from a first-beam wavelength of the first beam of light.

18. The computer system of claim 17 , wherein the processing component is configured to

Assignees

• Intermec Ip Corp
• Intermec Ip Corp

Inventors

• El Akel Khalid
• Stang Jean-Pierre
• Serres Bernard

Classifications

• G06K7/10851 Primary

  Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device (basic electronic circuitry H03) · CPC title

• G01B11/16

  for measuring the deformation in a solid, e.g. optical strain gauge · CPC title

• G01B11/25

  by projecting a pattern, e.g. {one or more lines,} moiré fringes on the object (G01B11/255 takes precedence {; image analysis for depth or shape recovery G06T7/50}) · CPC title

• G01B11/167

  by projecting a pattern on the object · CPC title

• G01B11/28

  for measuring areas · CPC title