Identification and localization of mobile robots

Patent metadata

Field	Value
Publication number	US-10814474-B2
Application number	US-201916422498-A
Country	US
Kind code	B2
Filing date	May 24, 2019
Priority date	Dec 20, 2018
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

Autonomous mobile robots may communicate with each other to avoid hazards, mitigate collisions, and facilitate the operation that they are intended for. To enhance such cooperation, it would be highly advantageous if each robot were able to determine which robot, among a plurality of other proximate robots, corresponds to each communication message. The specific identity of each robot is generally unknown to the other robots if a plurality of robots are in range. Systems and methods provided herein can enable robots and other equipped devices to determine the spatial location of each other robot in proximity, by detecting a pulsed localization signal emitted by each of the other robots. In addition, each robot can transmit a self-identifying code, synchronous with the emitted localization signal, so that other robots can associate the proper code with each robot. After such localization and identification, the robots can then cooperate more effectively in mitigating potential collisions.

First claim

What is claimed is:

1. A system, mounted on a first robot, for localizing a second robot, comprising:
a wireless transmitter configured to transmit a first wireless message;
a localization signal emitter configured to emit a first localization signal comprising pulsed visible or infrared light synchronized with the first wireless message;
a wireless receiver configured to receive a second wireless message from the second robot;
a localization signal detector configured to detect, and to determine an arrival direction of, a second localization signal from the second robot, the second localization signal comprising pulsed visible or infrared light synchronized with the second wireless message; and
a processor configured to cause the localization signal emitter to emit the first localization signal synchronously with the first wireless message, to determine a direction toward the second robot based at least in part on the arrival direction of the second localization signal, and to associate the second localization signal and the direction toward the second robot with the second wireless message.

2. The system of claim 1 , wherein the first wireless message includes a first predetermined non-transient identification code associated with the first robot, and the second wireless message includes a second predetermined non-transient identification code associated with the second robot.

3. The system of claim 1 , wherein the processor is further configured to perform one or more of the following steps:
determine which particular robot, among a plurality of other robots, is the second robot based at least in part on the direction toward the second robot, as determined from the arrival direction of the second localization signal;
decode a second identification code by analyzing the second localization signal;
identify the second robot by comparing an image of the second robot and the direction toward the second robot;
form a plurality of successive images of the second robot at successive times, and calculate an updated direction toward the second robot based on at least two of the plurality of images;
communicate with the second robot after determining both the direction toward the second robot and a pre-determined non-transient identification code associated with the second robot;
determine, based at least in part on one or more communications with the second robot, whether an imminent collision is avoidable or unavoidable;
avoid, in cooperation with the second robot, an imminent collision, if such avoidance is possible or
cause the second robot to avoid an imminent collision, at least in part by communicating with the second robot, if such avoidance is possible and necessary;
wherein the avoid, in cooperation with the second robot, an imminent collision, or the cause the second robot to avoid an imminent collision, includes the following steps:
avoid interference between the first and second robots by communicating wirelessly with the second robot after detecting the second localization signal and determining, according to the arrival direction of the second localization signal, which robot, among a plurality of robots proximate to the first robot, is the second robot;
determine a second predetermined non-transient identification code configured to persistently represent the second robot specifically, and then transmit, specifically to the second robot, a wireless message that includes the second identification code;
determine whether the second robot includes a localization system comprising a second localization signal emitter configured to emit the second localization signal, and a second localization signal detector configured to determine an arrival direction of the first localization signal;
prepare, in cooperation with the second robot, a first sequence of actions comprising a plurality of sequential positive accelerations, active or passive decelerations, waiting times, or steering actions of the first robot, and a second sequence of actions comprising a plurality of sequential positive accelerations, active or passive decelerations, waiting times, or steering actions of the second robot;
avoid a collision, at least in part by communicating with the second robot after determining the direction toward the second robot and a pre-determined non-transient identification code which is persistently associated with the second robot;
communicate with the second robot, and prepare, at least in part based on communications with the second robot, one or more sequences of actions configured to avoid the collision or to minimize the harm of an unavoidable collision, and to implement a selected one of the sequences of actions;
wait, after receiving a wireless message from the second robot, for a predetermined waiting interval, and then prepare a gate interval, and transmit a responsive wireless message at a randomly selected time during the gate interval; and
delay emitting the first localization message while another wireless message is in progress.

4. The system of claim 3 , wherein the processor is configured to wait, after receiving a wireless message from the second robot and determining that another wireless message has been transmitted during the predetermined waiting interval, for a second waiting interval, and then to prepare a second gate interval, and to emit a wireless message during the second gate interval.

5. The system of claim 4 , wherein the second waiting interval is shorter than the predetermined waiting interval.

6. The system of claim 1 , further including a visible-light or infrared camera configured to create an image of robots proximate to the first robot and of a particular localization signal comprising visible light or infrared pulses emitted by a particular one of the robots proximate to the first robot.

7. The system of claim 1 , wherein the first wireless message includes a first predetermined non-transient identification code persistently associated with the first robot, and the second wireless message includes a second pre-determined non-transient identification code associated with the second robot, and the processor is further configured to associate the second identification code with the second robot.

8. The system of claim 1 , wherein the first localization signal begins when the first wireless message ends, or the first wireless message begins when the first localization signal ends, or the first localization signal and the first wireless message are present at the same time, or the first localization signal is emitted responsive to a predetermined icon in the first wireless message.

9. The system of claim 1 , wherein the localization signal emitter is configured to emit the first localization signal in temporal proximity to the first wireless signal.

10. The system of claim 1 , wherein the localization signal emitter is configured to encode a first identification code in the first localization signal comprising a plurality of visible light or infrared pulses, by modulating a width of each pulse or by modulating intervals between the pulses.

11. The system of claim 1 , wherein the localization signal emitter is configured to emit the first localization signal such that the first localization signal is detectable to other robots proximate to the first robot regardless of the position of the other robots.

12. The system of claim 11 , wherein the first localization signal has azimuthal symmetry or spherical symmetry.

13. The system of claim 1 , wherein the first identification code is encoded in the first localization signal.

14. The system of claim 1 , wherein the system is mounted on an unoccupie

Assignees

• Newman David E
• Massengill R Kemp
• Autonomous Roadway Intelligence Llc

Inventors

• Newman David E
• Massengill R Kemp

Classifications

• G05B2219/39135

  For multiple manipulators operating at same time, avoid collision · CPC title

• B25J9/1682

  Dual arm manipulator; Coordination of several manipulators · CPC title

• B25J9/1676

  Avoiding collision or forbidden zones · CPC title

• B25J19/023

  including video camera means · CPC title

• B25J19/06 Primary

  Safety devices · CPC title