Optical tracking robot system

• US 4,627,511 A
• Filed: 10/07/1985
• Issued: 12/09/1986
• Est. Priority Date: 10/18/1984
• Status: Expired due to Term

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Yajima, Hiroshi
• Primary Examiner(s): Love, John J.
• Assistant Examiner(s): Camby, Richard M.
• Application Number:
  US06/785,162
• Time in Patent Office: 428 Days
• Field of Search: 180/167, 180/168, 180/169, 901/1, 901/47, 250/203 R, 250/491.1, 318/587, 364/424
• US Class Current: 180/167
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals

Abstract

In an optical tracking robot system, a target has a light emitting section with a high light emitting directivity, for emitting a light beam modulated into pulses. A tracking robot has a tracking sensor section for monitoring a light beam by a pair of light receiving elements, for processing signals from the received light beam, and for generating and supplying drive control signals to a travel control section. In response to drive control signals the travel control section generates and supplies drive signals to a driver section. The driver section drives the tracking robot so that the robot advances while turning to the right when the output level of the right side light receiving element is higher than that of the left side light receiving element, and to the left when the latter is higher than the former. The robot also has an approach sensor section which detects the light beam by means of a light receiving element, and generates and supplies stop control signals to the travel control section. The travel control section supplies stop signals to the driver section, thereby stopping the robot.

Claims

1. An optical tracking robot system comprising:

light emitting means attached to a target, said light emitting means including a source of operating voltage;

at least one light emitting element coupled to said operating voltage source for emitting a light beam modulated into pulses; and

modulator means for modulating the operating voltage of said light emitting element impulses;

tracking sensor means for monitoring the light beam emitted from said light emitting means and including means for generating drive control signals to determine the drive direction of a tracking robot;

approach sensor means including a light receiving element provided at a front portion of the tracking robot at a different height from said light emitting element, for detecting an approach to the target;

aperture means provided in front of said light receiving element for restricting the light receiving area of said light receiving element such that an approach detection distance from the target can be adjusted to a desired value;

an amplifier detector means including means for amplifying pulse signals received by said light receiving element, means coupled to said amplifying means for demodulating the amplified signals by means of a band-pass filter, and output means coupled to said demodulating means for generating an output signal; and

comparator means for comparing the level of the output signal generated by said output means of said amplifier detector means with a predetermined threshold level and generating stop control signals to stop the tracking robot based on the result of said comparison when the tracking robot approaches the target;

travel control means for receiving said drive control signals from said tracking sensor means and said stop control signals from said approach sensor means and for generating drive signals and stop signals; and

driver means for driving the tracking robot in response to said drive signals from said travel control means and for stopping the robot in response to said stop signals from said travel control means.

2. The optical tracking robot system of claim 1, wherein said tracking sensor means comprises:

a pair of light receiving elements provided at the front of the tracking robot, said pair of light receiving elements having receiving areas which are arranged to receive light from respective different directions, the light receiving areas of said pair of light receiving elements overlapping each other, said pair of light receiving elements receiving said light beam emitted by said light emitting means;

a pair of amplifier-detector means coupled to respective ones of said pair of light receiving elements, each of said amplifier-detector means including means for amplifying a pulse signal received by its associated light receiving element, means including a band-pass filter for detecting and demodulating the amplified signal, and means for outputting a signal corresponding to said detected and demodulated signal; and

a pair of A/D convertor means coupled to respective ones of said amplifier-detector means for converting the output signals from its associated amplifier-detector means into said drive control signal, said drive control signals being supplied to said travel control means.

3. The optical tracking robot system of claim 2, wherein said drive control signals are digital signals, each comprising a plurality of bits.

4. The optical tracking robot system of claim 3, wherein said stop control signals are one-bit digital signals.

5. The optical tracking robot system of claim 1, wherein said stop control signals are one-bit digital signals.

6. The optical tracking robot system of claim 1, wherein said aperture means comprises an adjustable aperture means.

7. The optical tracking robot system of claim 1, wherein said light receiving element of said approach sensor means has a diagonally downward light receiving directivity.

8. The optical tracking robot system of claim 2, wherein said pair of light receiving elements of said tracking sensor means are provided at the front portion of the tracking robot and are horizontally spaced from each other, the light receiving areas of said pair of light receiving elements including said overlapping area and including horizontally spaced non-overlapping areas, said overlapping areas being located between said non-overlapping areas.

9. The optical tracking robot system of claim 8, wherein said drive control signals determine the left and right drive direction of said tracking robot.

10. The optical tracking robot system of claim 1, wherein said drive control signals determine the left and right drive direction of said tracking robot.