JP4479578B2 - Emergency stop system for mobile robot - Google Patents

Description

The present invention relates to an emergency stop system for a mobile robot. More specifically, the present invention relates to an emergency stop system for an autonomous mobile robot including a self-position detecting device that detects a self-position of the robot.

  An apparatus for detecting a position by using radio waves or ultrasonic waves has been developed. An autonomous mobile robot has been developed that incorporates this device in a robot, receives the radio waves flying into the robot's activity range, and detects the position of the robot by analyzing the received radio waves. As the self-position detection technique, a technique similar to GPS that detects a position by receiving a radio wave transmitted from an artificial satellite is used.

  In addition to the method described above, the self-position detection method detects the robot's self-position by transmitting ultrasonic waves toward the robot's activity range and analyzing the reception timing of the ultrasonic waves received by the robot. can do. Alternatively, by mounting a radio wave radar or an ultrasonic radar on the robot, the position of the radar can be detected to detect the self position of the robot.

  Such an autonomous mobile robot is expected to replace human work and perform cooperative work in the same environment as humans. Therefore, there may be various things such as a structure, an apparatus, or an instrument in the work environment of the robot. If the robot performs work in such an environment, there is a risk of interference with people or objects. In the case of interference, it is necessary to stop the robot quickly and safely.

  For this reason, various emergency stop devices for robots have been developed. For example, as disclosed in Japanese Patent Publication No. 4-11356, a stop signal is transmitted to the robot by radio or infrared, or a sound wave having a specific frequency is disclosed as disclosed in Japanese Patent Laid-Open No. 5-318431. Some are used as stop signals.

Japanese Examined Patent Publication No. 4-11356 Japanese Patent Laid-Open No. 5-318431

  However, since the conventional emergency stop device described above uses a stop signal by radio, infrared, or sound wave, the stop signal may not be received by the robot due to an unexpected disturbance. That is, there is a possibility that the robot cannot be stopped reliably. For example, when a plurality of robots are operated cooperatively, a signal transmitted from each robot to the controller (command side) or a signal transmitted from the controller to each robot interferes, and each robot generates a stop signal. The robot may not be able to receive and the robot may not stop. In addition, there is a possibility that the robot does not stop because it enters the shadow of a plurality of robots and the stop signal does not physically reach the robot.

  Furthermore, in recent years, since robots are used in various environments, stop signals are received due to the occurrence of unexpected disturbances from radio signals and electrical products other than signals transmitted and received between the controller and the robot. There are cases where this is not possible.

Accordingly, the present invention has been made to solve the above-described problems, and is an autonomous mobile type that can surely make an emergency stop even when the robot cannot receive an emergency stop signal. It is an object to provide an emergency stop system for a robot.

Emergency shutdown system of the autonomous mobile robot according to the present invention has been made in order to solve the above problems, the emergency stop system of the autonomous mobile robot to operate in accordance with a command signal from the controller installed in the robot outside, A receiving means for receiving the command signal and the self-position detection signal, comprising: a self-position detection signal sending means for sending and stopping a self-position detection signal for detecting the self-position of the robot; Control means for controlling the operation of the robot based on the contents of the command signal and the self-position detection signal received by the robot, and the control means has an emergency stop signal as the command signal. when receiving, or the receiving the self-position detecting signal transmitter stops the self-position detecting signal When the stage stops receiving the self-position detection signal, it is characterized in that for emergency stop the robot.

In this emergency stop system , when the receiving means receives the emergency stop signal, the robot is emergency stopped by the control means. Since this emergency stop signal is transmitted to the robot by radio, there is a possibility that the receiving means cannot receive the emergency stop signal as in the conventional apparatus. However, in this emergency stop system , even when the receiving means does not receive the self-position detection signal, the robot is emergency stopped by the control means.

  Here, since the self-position detection signal transmission means for transmitting the self-position detection signal can be controlled on the command side, the reception means does not receive the self-position detection signal by stopping the transmission of the self-position detection signal Can produce. Therefore, when the robot is to be emergency stopped, the emergency stop signal is transmitted on the command side and the transmission of the self-position detection signal is stopped, so that the robot can be surely emergency stopped.

That is, in this emergency stop system , when an emergency stop signal is received by the receiving means, the robot is emergency stopped by the control means based on the emergency stop signal, as in the prior art. Even when the emergency stop signal is not received by the receiving means, since the transmission of the self-position detection signal is stopped, the receiving means does not receive the self-position detection signal. For this reason, the robot is brought to an emergency stop by the control means. Therefore, even when the robot cannot receive the emergency stop signal, the robot can be surely emergency stopped.

The emergency stop system for an autonomous mobile robot according to the present invention comprises a plurality of the self-position detection signal transmitting means, and the control means receives the emergency stop signal as the command signal when the receiving means, or It is desirable that the robot is brought to an emergency stop when all of the self-position detection signals from the self-position detection signals are not received.

  When only one self-position detection signal transmission means is provided, when signal transmission from the self-position detection signal transmission means is stopped, signal transmission from the self-position detection signal transmission means is stopped due to an emergency stop. The case may be due to a failure of the self-position detection signal transmission means or the like. For this reason, even if the signal transmission is stopped due to a failure of the self-position detection signal transmission means or the like, the robot is brought to an emergency stop.

Therefore, in this emergency stop system for an autonomous mobile robot, a plurality of self-position detection signal transmission means are provided, and when the receiving means receives an emergency stop signal as a command signal by the control means, or from each self-position detection signal. When all of the self-position detection signals are not received, the robot is caused to make an emergency stop. As a result, the possibility that all the self-position detection signal transmission means will fail at the same time is very low, so even if the signal transmission is stopped due to a failure, the reception means is The self-position detection signal transmission can be received. Therefore, when the transmission of the self-position detection signal is stopped due to a failure of the self-position detection signal transmission device or the like, the robot continues the normal operation without making an emergency stop. That is, in this emergency stop system , the robot can be surely made to make an emergency stop only when an emergency stop is required.

In the emergency stop system for an autonomous mobile robot according to the present invention, when the controller transmits an emergency stop signal as the command signal, the self-position detection signal transmitted from the self-position detection signal transmission means. It is desirable to stop.

  By doing so, since the transmission of the self-position detection signal is stopped only by issuing the emergency stop signal, the operator only has to perform the same operation as before.

According to the emergency stop system for an autonomous mobile robot according to the present invention, as described above, the autonomous mobile type can reliably stop the robot even when the robot cannot receive the emergency stop signal. A robot emergency stop system is provided.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a most preferred embodiment that embodies an emergency stop system for an autonomous mobile robot according to the present invention will be described in detail with reference to the drawings. In this embodiment, a case where two biped walking robots are operated cooperatively will be described.

  First, the mechanical configuration of the robot will be briefly described with reference to FIG. FIG. 1 is a skeleton diagram showing the mechanical configuration of the robot. In the robot 50, both legs and both arms are swingably connected to the trunk (torso), and each joint has actuators 1 to 17 with encoders. Specifically, the robot 50 includes two actuators 1, 2, 6 and 7 at the left and right hip joints, respectively, and has two axes of freedom. Similarly, the robot 50 is provided with the actuator 17 at the hip joint and has one axis of freedom, the actuators 3 and 8 are provided at the left and right knee joints, respectively, and has one axis of freedom, and the left and right ankles. The joints are provided with actuators 13 and 16, respectively, and have one axis of freedom. Thereby, the robot 50 can adjust each joint angle by operation | movement of each actuator 1-17, and can measure each joint angle.

  Next, the operating environment of the robot will be described with reference to FIG. FIG. 2 is an explanatory diagram schematically showing the state of the operating environment of the robot. The above-described robot 50 is basically operated by the controller 60. Further, three self-position detection signal transmission devices 20 that transmit the self-position detection signal 21 are provided in the activity range of the robot 50. Thereby, the self-position detection signal 21 jumps over the entire range of the robot 50. The self-position detection signal transmission device 20 may be installed in an optimal number (the number of self-position detection signals that can fly over the entire activity range) as appropriate based on the size of the activity range of the robot 50. The self-position detection signal 21 is received by the robot 50 (more precisely, a computer device 30 described later), and the self-position is detected by analyzing the received self-position detection signal 21. As the self-position detection signal 21, for example, infrared rays, lasers, radio waves, ultrasonic waves, radio wave radars or ultrasonic radars, or a combination thereof (for example, indoor GPS or signals using infrared rays and lasers) are used. can do.

  In the present embodiment, indoor GPS is used as the self-position detection signal transmission device. In indoor GPS, an infrared LED and a laser are transmitted, and the robot receives these to detect its own position. The reason why the indoor GPS is used is to avoid interference with various radio waves.

  In this embodiment, as shown in FIG. 2, the two robots 50 and 50 are operated cooperatively. The robots 50 and 50 are configured to operate based on commands from the controller 60. Further, the controller 60 is provided with an emergency stop button 61 (see FIG. 3) for emergency stopping the robot 50. The command from the controller 60 is transmitted to the robots 50 and 50 by radio. In addition, the status data of the robots 50 and 50 is transmitted to the controller by radio.

  Next, the operation (walking operation) of the robot 50 will be briefly described with reference to FIG. FIG. 3 is a perspective view simply showing how the robot walks. The robot 50 operates by changing the relative postures of both feet and arms with respect to the trunk according to the gait data indicating the positions of the trunk, left toe, right foot, left hand and right hand. ing. More specifically, in the present embodiment, while the right foot 22 of the robot 50 is in contact with the ground, the left foot 24 is moved as a free leg like a track 24a, and when the left foot 24 touches, this time the right foot 22 is used as a free leg. It moves like 22a. Thereafter, similarly, the left foot 24 is moved as a free leg like a track 24b, and then the right foot 22 is moved as a free leg like a track 22b to continue walking. Also, both arms 26 and 27 can be operated on the same principle as both feet 22 and 24.

  Here, in order for the robot 50 to continue walking, data for storing the reference position W of the trunk and the trajectories 22a, 22b, 24a, and 24b of both toes (left toe Lf, right toe Rf) is necessary. Further, in order to move both arms 26 and 27, data for storing the reference position W of the trunk and the trajectories of both hands (left hand tip Lh, right hand tip Rh) is necessary. Therefore, a computer device 30 (see FIG. 4) for creating such data (gait data) is built in the robot 50. The computer device 30 corresponds to “reception unit” and “control unit” of the present invention. Since the hardware configuration of the computer device 30 is the same as that of a general-purpose computer, description thereof is omitted.

  The gait data indicates the positions of the trunk, both feet, and both hands in a global coordinate system that defines the coordinates of the space in which the robot 50 is active. Here, in order to indicate the positions of the trunk, both feet, and both hands, reference points are defined on the trunk, left foot, right foot, left hand, and right hand, respectively. The gait data is a global coordinate system that indicates the positions of the trunk reference point, the left foot reference point, the right foot reference point, the left hand reference point, and the right hand reference point over time. Coordinate data (x, y, z) is provided. The coordinate data (x, y, z) changes with the elapsed time t from the start of the operation of the robot 50.

  As shown in FIG. 4, the robot 50 includes devices (joint angle group calculation device 31 and actuator control device 32) for moving the robot 50, as shown in FIG. 4. Further, the computer device 30 stores a data group (basic gait data) for determining the posture of the robot 50. The computer device 30 controls the joint angle group calculation device 31 and the actuator control device 32 based on the stored basic gait data. FIG. 4 is a block diagram showing a robot control system.

  Here, the joint angle group calculation device 31 solves so-called inverse kinematics from the gait data (Lfs (t), Rfs (t), Lhs (t), Rhs (t), Ws (t)). The joint angle is calculated. Then, the joint angle group calculation device 31 sends the calculated joint angle group to the actuator control device 32. The actuator control device 32 controls driving of the actuators 1 to 17 of each joint of the robot 50. Then, the actuator control device 32 controls the driving of the actuators 1 to 17 of each joint based on the joint angle group sent from the joint angle group calculation device 31 and calculates the joint angle of the robot 50. It is supposed to adjust to.

  In addition, the computer device 30 receives the self-position detection signal 21 transmitted from the self-position detection signal transmission device 20, analyzes the received self-position detection signal 21, detects the self-position, and sets the self-position detection signal to the self-position. Based on the gait data.

  Next, an emergency stop of the robot 50 will be described with reference to FIGS. FIG. 5 is an explanatory diagram schematically showing the state of the operating environment of the robot when the emergency stop process is executed. FIG. 6 is a flowchart showing the contents of the emergency stop process. The emergency stop of the robot is executed by pressing the emergency stop button 61 according to the judgment of the operator. In the present embodiment, for example, when the robots 50 and 50 interfere with each other (or when they are likely to interfere), the emergency stop button 61 is pressed.

  When the emergency stop button 61 is pressed by the operator, an emergency stop command is transmitted from the controller 60 to the computer devices 30 and 30 of the robots 50 and 50. In addition, the controller 60 turns off all of the self-position detection signal transmission devices 20, 20, 20 and stops the transmission of the self-position detection signals 21, 21, 21. As a result, as shown in FIG. 5, the self-position detection signals 21, 21, 21 from the self-position detection signal transmission devices 20, 20, 20 do not fly within the activity range of the robots 50, 50.

  On the other hand, in the robot 50, the emergency stop processing subroutine shown in FIG. Here, the contents of this processing will be described. First, it is determined whether an emergency stop command has been received (S1). At this time, when an emergency stop command is received (S1: YES), the computer device 30 returns the actuators 1 to 17 to the initial state via the actuator control device 32 and stops the robot 50 (S3). Then, the subroutine processing is terminated. On the other hand, if the emergency stop command has not been received (S1: NO), it is determined whether any of the self-position detection signals 21, 21, 21 has been received (S2).

If none of the self-position detection signals 21, 21, 21 has been received in S 2 (S 2: YES), the computer device 30 returns the actuators 1 to 17 to the initial state via the actuator control device 32. The robot 50 is stopped (S3). Then, the subroutine processing is terminated. On the other hand, if any of the self-position detection signals 21, 21, 21 is received (S2: NO), the processing of this subroutine is terminated. That is, the robot 50 continues normal operation.
In the process of S3, if the robot 50 does not fall, the actuators 1 to 17 may be stopped immediately without returning to the initial state.

  As described above, the robot 50 is to make an emergency stop when the emergency stop command is received (S2: YES) or when none of the self-position detection signals 21, 21, 21 is received (S2: YES). Become. Here, when the robot 50 is to be emergency stopped only by the emergency stop command as in the prior art, the emergency stop command is transmitted wirelessly in the present embodiment. There is a possibility that the robot 50 does not receive the stop command. However, in this embodiment, even if the emergency stop command is not received by the robot 50, the robot 50 is emergency stopped when none of the self-position detection signals 21, 21, 21 is received. .

  In the present embodiment, when the robot 50 is to be brought to an emergency stop, the emergency stop button 61 is pressed by the operator. Then, the controller 60 transmits an emergency stop command to the robot 50 and stops the transmission of the self-position detection signals 21, 21, and 21. Accordingly, even when the robot 50 cannot receive the emergency stop command, the transmission of the self-position detection signals 21, 21, and 21 is all stopped, so that the robot 50 can be surely emergency stopped. it can.

  Here, even when the self-position detection signal transmission device 20 fails for some reason, the transmission of the self-position detection signal 21 may be stopped. However, in this embodiment, three self-position detection signal transmitters 20 are provided, and it is very unlikely that all the self-position detection signal transmitters 20 will simultaneously fail. For this reason, even if any of the self-position detection signal transmission devices 20 breaks down, the computer device 30 can receive the self-position detection signal 21 from the self-position detection signal transmission device 20 that has not failed. Thereby, the robot 50 continues normal operation without an emergency stop. That is, in the present embodiment, the robot 50 can be surely made to make an emergency stop only when the robot 50 needs to be made an emergency stop.

As described above, according to the emergency stop system according to the present embodiment, when the emergency stop button 61 is pressed by the operator, the controller 60 transmits an emergency stop command to the robot 50. All transmissions of the self-position detection signals 21, 21, 21 are stopped. Then, when the computer device 30 of the robot 50 receives an emergency stop command from the controller 60, the robot 50 is emergency stopped. Even when the computer device 30 of the robot 50 cannot receive the emergency stop command, since the transmission of the self-position detection signals 21, 21, 21 is all stopped, the robot 50 Stop. As described above, according to the emergency stop system according to the present embodiment, even when the robot 50 cannot receive the emergency stop command, the robot 50 can be surely stopped.

  It should be noted that the above-described embodiment is merely an example and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, the case where the present invention is applied to a biped robot is illustrated, but the present invention is not limited to a biped robot, and the present invention is not limited to a robot to which an emergency stop signal is not given by wire. Can be applied. Specifically, for example, an autonomous mobile robot working in a factory that may adversely affect radio signals because various facilities and machines are installed, or various electrical appliances and OA devices are installed. Therefore, the present invention can be applied to an autonomous mobile robot working in a home or office that may adversely affect a radio signal.

It is a skeleton figure which shows the machine structure of a robot. It is explanatory drawing which shows the state of the operating environment of a robot typically. It is the perspective view which showed a mode that the robot walked simply. It is a block diagram which shows the control system of a robot. It is explanatory drawing which shows typically the state of the operating environment of a robot when an emergency stop process is performed. It is a flowchart which shows the content of an emergency stop process.

Explanation of symbols

1 to 17 Actuator 20 Self-position detection signal transmitter 30 Computer device 31 Joint angle group calculator 32 Actuator controller 50 Robot 60 Controller 61 Emergency stop button

Claims (3)

In an emergency stop system for an autonomous mobile robot that operates based on command signals from a controller installed outside the robot,
A self-position detection signal transmission means for transmitting and stopping a self-position detection signal for detecting the self-position of the robot is provided outside the robot .
A receiving means for receiving the command signal and the self-position detection signal, and a control means for controlling the operation of the robot based on the contents of the command signal and the self-position detection signal received by the receiving means . In preparation for
The control means receives the emergency position signal as the command signal, or the self-position detection signal transmission means stops the self-position detection signal and the receiving means receives the self-position detection signal. An emergency stop system for an autonomous mobile robot characterized in that when the robot stops running, the robot is emergency stopped. In the emergency stop system of the autonomous mobile robot according to claim 1,
A plurality of self-position detection signal transmission means,
The control means makes the robot make an emergency stop when the receiving means receives an emergency stop signal as the command signal or when it does not receive all of the self-position detection signals from the self-position detection signals. An emergency stop system for autonomous mobile robots. In the emergency stop system of the autonomous mobile robot according to claim 1 or 2,
Wherein the controller, when transmitting an emergency stop signal as the command signal, the emergency stop system of the autonomous mobile robot, characterized in that stops the self-position detecting signal transmitted from the self-position detecting signal transmitter.

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