Positioning an object with respect to a target location

• US 10,083,331 B2
• Filed: 05/09/2017
• Issued: 09/25/2018
• Est. Priority Date: 09/11/2015
• Status: Active Grant

• Current Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Original Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Inventors: Ackley, H. Sprague, Stang, Jean-Pierre, El Akel, Khalid
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US15/590,599
• Publication Number:
  US 20170243039A1
• Time in Patent Office: 504 Days
• Field of Search: 23546224
• CPC Class Codes: G06K 2007/10524 Hand-held scanners
• CPC Class Codes: G06K 7/10554 Moving beam scanning
• CPC Class Codes: G06K 7/10752 Exposure time control
• CPC Class Codes: G06K 7/10831 Arrangement of optical elements, e.g. lenses, mirrors, prisms optical elements per se G02B
• CPC Class Codes: G06K 7/1413 1D bar codes

Abstract

Systems and methods are provided for positioning an object with respect to a target location, such as for auto-focusing. One implementation includes a positioning device, which includes a reference object having a plurality of dark-shaded bars arranged in parallel with and separated from each other by spaces equal to a width of each of the bars. The positioning device also includes a motor configured to move in a reciprocating manner and a sensor configured to sense at least one of the bars or spaces. The motor is connected to the reference object or the sensor and moves the reference object or sensor with respect to the other. The motor is configured to stop at a target location in two phases of motion.

Claims

1. A method for positioning an object, the method comprising the steps of:

providing an optical grid having a first set of optical elements and a second set of optical elements, the first set of optical elements being optically distinguishable from the second set of optical elements;

moving an optical sensor in a forward direction with respect to the optical grid, wherein transitions are encountered when the optical sensor senses a border between one of the first set of optical elements and one of the second set of optical elements;

beginning a clock cycle counter when a target location is reached;

stopping the clock cycle counter when a first transition beyond the target location is encountered to obtain a first clock cycle count;

continuously moving the optical sensor in the forward direction until at least a second transition beyond the target location is encountered;

reversing the direction of movement of the optical sensor and moving the optical sensor in a reverse direction;

resetting and beginning the clock cycle counter a second time when the first transition beyond the target location is encountered in the reverse direction; and

stopping the movement of the optical sensor when the clock cycle counter reaches the first clock cycle count.

2. The method of claim 1, wherein the optical sensor is coupled in a fixed relationship to the object, whereby the object is positioned with respect to the target location.

3. The method of claim 1, wherein the first set of optical elements includes a plurality of parallel dark-shaded or opaque bars and the second set of optical elements includes a plurality of parallel light-shaded or transparent bars, the dark-shaded or opaque bars being parallel with and interspersed with the light-shaded or transparent bars.

4. The method of claim 3, wherein the width of each of the bars of the first and second sets of optical elements is the same.

5. The method of claim 1, comprising utilizing a piezo motor to move the optical sensor in the forward and reverse directions.

6. The method of claim 1, wherein the target location is positioned between two adjacent transitions.

7. The method of claim 1, wherein at least the second transition beyond the target location includes a plurality of transitions.

8. A method comprising:

moving, to a target location, either

a reference object including a plurality of shaded or opaque bars arranged in parallel with and separated from each other by spaces or

a sensor configured to sense at least one of the bars and spaces of the reference object,

wherein the moving to the target location consists essentially of;

moving in a forward direction, with a motor, either the reference object or the sensor;

stopping the movement in the forward direction;

moving in a reverse direction, with the motor, either the reference object or the sensor; and

stopping the movement in the reverse direction, comprising stopping, with the motor, either the reference object or the sensor at the target location.

9. The method of claim 8, wherein:

the method comprises sensing the target location while moving in the forward direction, and counting clock cycles until a first transition beyond the target location is encountered; and

the stopping the movement in the forward direction comprises stopping after at least a second transition beyond the target location is reached.

10. The method of claim 9, wherein:

the counting the clock cycles until the first transition beyond the target location is encountered provides a first count; and

the method comprises;

beginning counting, during the moving in the reverse direction, clock cycles when the first transition beyond the target location is reached to provide a second count, and

stopping the movement of the motor when the second count is the same as the first count.

11. The method of claim 10, wherein each transition is an intersection between a bar and a space.

12. The method of claim 8, wherein a plurality of sensors are arranged on the motor.

13. The method of claim 8, wherein an optical lens is connected to the motor.

14. The method of claim 8, wherein the motor is incorporated in a housing of a barcode scanner.

15. A method, comprising:

moving an optical sensor in a forward direction with respect to an optical grid, wherein the optical grid comprises a first set of optical elements and a second set of optical elements, the first set of optical elements being optically distinguishable from the second set of optical elements, wherein transitions are encountered when the optical sensor senses a border between one of the first set of optical elements and one of the second set of optical elements;

beginning a clock cycle counter when a target location is reached;

stopping the clock cycle counter when a first transition beyond the target location is encountered to obtain a first clock cycle count;

continuously moving the optical sensor in the forward direction until at least a second transition beyond the target location is encountered;

reversing the direction of movement of the optical sensor and moving the optical sensor in a reverse direction;

resetting and beginning the clock cycle counter a second time when the first transition beyond the target location is encountered in the reverse direction; and

stopping the movement of the optical sensor when the clock cycle counter reaches the first clock cycle count.

16. The method of claim 15, wherein the optical sensor is coupled in a fixed relationship to the object, whereby the object is positioned with respect to the target location.

17. The method of claim 15, wherein the first set of optical elements includes a plurality of parallel dark-shaded or opaque bars and the second set of optical elements includes a plurality of parallel light-shaded or transparent bars, the dark-shaded or opaque bars being parallel with and interspersed with the light-shaded or transparent bars.

18. The method of claim 17, wherein the width of each of the bars of the first and second sets of optical elements is the same.

19. The method of claim 15, comprising utilizing a piezo motor to move the optical sensor in the forward and reverse directions.

20. The method of claim 15, wherein the target location is positioned between two adjacent transitions.