JP4155804B2 - Control device for legged mobile robot - Google Patents

Description

【００８６】
図６及び図７に示すように、機体上で挟み込みを起こす危険があると推測される部位１８箇所に、挟み込みセンサを配設している。
【００８７】
挟み込みセンサが挟み込みを検出するための挟み込み条件を定量的にするために、本発明者らは、人の指や爪について、挟み込みに対して耐えられる痛さの限界力の調査を実施した。下表には、この限界力テストの結果をまとめている。但し、指を押す物はステンレス製φ１２ｍｍの円柱とアルミ製平板の２種類とし、測定箇所は、人差し指の指先腹、爪、第１関節爪側、指先側面の４箇所とした。
【００８８】
【表２】

【００８９】
限界力テストの結果、挟み込み条件の最低荷重は２ｋｇであることが確認された。これを基に、本実施形態では、挟み込みセンサで感知する感圧力を２ｋｇと設定する。
【００９０】
挟み込みセンサは、例えばシート状の感圧センサ(シート面全体で力を感じる)、これにより挟み込む部分を広範囲にカバーし、安全性が高まる。感圧センサの取付け範囲は、ロボット可動部とロボット自身の部位との接触点と回転軸との隙間とする。
【００９１】
人の手や指などが、その挟み込み力が２ｋｇを超えると、ロボットの動作が停止され、部位毎の条件によって挟んだ部位を瞬時に開く動作をしたり、瞬時に脱力したり、ロボットの姿勢状況毎に対応挙動を選択する。これにより、ロボットが姿勢を崩し転倒したりすることによる人への２次災害を回避する。
【００９２】
また、回転軸にトルク・リミッタ機構を備え、ロボット筐体表面に柔軟で手、指などへの挟み込み力を分散し、危害を軽減、手・指などをロボット筐体表面の摩擦等により咥え込まないような形状、摩擦特性を持つ材料を備えるものとする。安全上、抜ける方向は前でも後ろでも構わないが、咥え込まれてロボット転倒時に一緒に持っていかれることを避けなければならない。指を咥え込んだまま機体が転倒すると非常に危険である。
【００９３】
本実施形態では、各部位毎に、挟み込みを検出したときのロボットの対処動作としての適応制御方法を割り当てている。また、各部位毎に、センサ感圧力やトルク・リミット値を適量にする。センサ出力により挟み込みが検知されたら、瞬時に該当する可動部用アクチュエータの動作を止め、アクチュエータのトルク又は力を減じ、該当する可動部を開放する方向にアクチュエータを動かす。
【００９４】
また、本実施形態では、ロボットの姿勢状況毎に、挟み込みを検出したときのロボットの対処動作としてのロボットの適応制御方法を割り当てる。センサ出力により挟み込みが検知されたら、瞬時に該当する可動部用アクチュエータの動作を止め、アクチュエータのトルク又は力を減じ、姿勢を大きく崩し転倒することによる２次災害を回避しつつ、該当する可動部を開放する方向にアクチュエータを動かす。
【００９５】
特に、脚の状態姿勢に応じて挟み込みセンサの検知後の対応方法を変えることで、アクチュエータのトルク又は力を減じ、姿勢を大きく崩し転倒することによる２次災害を回避する。例えば、片足接地時、両足接地時、動態時、静止時毎の対応動作を実行する。
【００９６】
図８には、脚についての挟み込みセンサによる適応姿勢・挙動の動作手順をフローチャートの形式で示している。このような動作手順は、ロコモーション生成部１４又はモーション再生部１５がエラー検出部１６からのエラー通知に応答して実行する。同図に示すように、足が地面に接地しているか否か、歩行中か立ち止まっているかにより、適応方法を選択するようになっている。
【００９７】
挟み込みセンサを検知したときのロボットの姿勢状態が動態接地の場合、さらに、その接地状態を確認する（ステップＳ１）。
【００９８】
両足接地の場合には、挟んだ軸を開放するように動き、転倒しないように他方の脚でバランスをとり（ステップＳ２）、安定姿勢へと移行する。
【００９９】
また、片足接地の場合、挟んだ軸を開放するように動き、接地していない他方の脚を接地し、バランスをとるように適応制御して（ステップＳ３）、両足で安定姿勢をとるようにする。
【０１００】
ここで、ステップＳ２又はＳ３において、バランスをとることに失敗した場合には、安全な転倒制御に従い、機体が倒れることによって、安全を確保する（ステップＳ４）。
【０１０１】
一方、挟み込みセンサを検知したときのロボットの姿勢状態が静態接地の場合、片足、両足ともに接地状態にし（ステップＳ５）、挟んだ軸を開放する様に元の姿勢に戻り（ステップＳ６）、安定姿勢を保つ。
【０１０２】
ここで、元の姿勢に戻ることができない場合には、安全な転倒制御に従い、機体が倒れることで、安全を確保する（ステップＳ７）。
【０１０３】
ステップＳ４又はＳ７において、挟み込み回避の動作により、ロボットが転倒した場合、人や周辺への危害を防止するために、転倒の姿勢や転倒動作の適応制御方法を割り当てる。
【０１０４】
また、男女年齢やその他の条件など、ユーザ毎に挟み込みセンサの検知する力を変えるようにしてもよい。ユーザ固有の条件等については、視覚や音声で認識する。
【０１０５】
この場合、接触するユーザの体格など手の大きさや耐力によって適用する挟み込みセンサが検知する値をレベル分けし、ユーザに適した対応ができるようにする。例えば、下記表のようにあらかじめモード（ＡＢＣ・・）を分けておく。小さな子供や女性の場合、センサの検知する力の大きさを小さくし、より安全性を高める。この場合、アプリケーションレベルも場合分けされる（ゲイン値・動作速度の調整など）。
【０１０６】
【表３】

【０１０７】
また、部位毎に挟み込みセンサで検知する力を変えるようにしてもよい。また、部位によって挟み込み形状や挟まれるモーメント位置によって検知する力を変えるようにしてもよい。
【０１０８】
［追補］
以上、特定の実施例を参照しながら、本発明について詳解してきた。しかしながら、本発明の要旨を逸脱しない範囲で当業者が該実施例の修正や代用を成し得ることは自明である。
【０１０９】
本発明の要旨は、必ずしも「ロボット」と称される製品には限定されない。すなわち、電気的若しくは磁気的な作用を用いて人間の動作に似せた運動を行う機械装置であるならば、例えば玩具等のような他の産業分野に属する製品であっても、同様に本発明を適用することができる。
【０１１０】
要するに、例示という形態で本発明を開示してきたのであり、本明細書の記載内容を限定的に解釈するべきではない。本発明の要旨を判断するためには、冒頭に記載した特許請求の範囲の欄を参酌すべきである。
【０１１１】
【発明の効果】
以上詳記したように、本発明によれば、自由度の高い脚式移動ロボットが作業中に安全を確保することができる、優れた制御装置を提供することができる。
【０１１２】
また、本発明によれば、脚式移動ロボットの作業中にオペレータや近隣のユーザを巻き込んだ事故を回避することができる、優れた制御装置を提供することができる。
【０１１３】
また、本発明によれば、脚式移動ロボットの作業中に可動部の動作によって人の手指などを挟み込む危害を好適に防止することができる、優れた制御装置を提供することができる。
【０１１４】
本発明に係る脚式移動ロボットの制御装置によれば、オペレータとの間で触覚を利用した接触による情報の授受を行なうときに、手や指などを挟み込まれる危険をなくすことができる。したがって、安全なロボットを提供することができ、加えて恐怖感などを人に与えることがなくなり、ロボットとの情報授受を安心して楽しめるという効果がある。
【図面の簡単な説明】
【図１】本発明の実施に供される脚式移動ロボット１００が直立している様子を前方から眺望した様子を示した図である。
【図２】本発明の実施に供される脚式移動ロボット１００が直立している様子を後方から眺望した様子を示した図である。
【図３】脚式移動ロボット１００の自由度構成を模式的に示した図である。
【図４】脚式移動ロボットに適用される制御システムの機能構成を模式的に示した図である。
【図５】歩行操作時における脚式移動ロボットのエラー検出処理の手順を示したフローチャートである。
【図６】脚式移動ロボット１００の各部位への挟み込みセンサの配置例を示した図である。
【図７】脚式移動ロボット１００の各部位への挟み込みセンサの配置例を示した図である。
【図８】脚についての挟み込みセンサによる適応姿勢・挙動の動作手順を示したフローチャートである。
【符号の説明】
１１…ロボットの各リソースの管理及び姿勢遷移制御モジュール
１２…復帰マネージャ
１３…エージェント
１４…ロコモーション生成部
１５…モーション再生部
１６…エラー検出部
１７…ゲート
１８…デバイス・マネージャ
１９…ゲートウェイ
２０…思考系モジュール
３０…遠隔操作系
３１…ＰＣアプリケーション
３２…入力デバイス[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a legged mobile robot having at least a plurality of movable legs, and more particularly to a control device for ensuring safety of a legged mobile robot having a high degree of freedom during work.
[0002]
More particularly, the present invention relates to a control device for avoiding an accident involving an operator or a nearby user during work of a legged mobile robot, and more particularly, by operation of a movable part during work of a legged mobile robot. The present invention relates to a control device for preventing the danger of pinching human fingers and the like.
[0003]
[Prior art]
A mechanical device that uses an electrical or magnetic action to perform a movement resembling human movement is called a “robot”. It is said that the word “robot” comes from the Slavic word “ROBOTA (slave machine)”. In Japan, robots began to spread from the end of the 1960s, but many of them are industrial robots such as manipulators and transfer robots for the purpose of automating and unmanned production operations in factories. Met.
[0004]
Recently, research and development on legged mobile robots simulating the body mechanisms and movements of biped upright walking such as humans and monkeys has progressed, and expectations for practical use are also increasing. Leg type movement with two legs standing up is unstable and difficult to control posture and walking, compared to crawler type, four or six legs type, etc., but walking with irregularities on the work path such as rough terrain and obstacles It is excellent in that it can realize flexible movement work, such as being able to cope with discontinuous walking surfaces such as up and down of surfaces and stairs and ladders.
[0005]
A legged mobile robot that reproduces a human biological mechanism and movement is particularly called a “humanoid” or “humanoid robot”. The humanoid robot can provide, for example, life support, that is, support for human activities in various situations in daily life such as a living environment.
[0006]
Most of the human working space and living space are formed according to the human body mechanism and behavioral style of biped upright walking, and the current mechanical system that uses wheels and other driving devices as moving means to move There are many barriers. Therefore, in order for the mechanical system, that is, the robot to perform various human tasks and penetrate deeply into the human living space, it is preferable that the movable range of the robot is substantially the same as that of the human. This is also why the practical application of legged mobile robots is highly expected.
[0007]
A legged mobile robot with a high degree of freedom is assumed to be used in any environment, and there are many scenes that deviate from the operating conditions guaranteed by the control system of the aircraft.
[0008]
In addition, robots that have mechanical moving parts and are intended for exchanging information and entertainment with humans through the movement of the moving parts are robots such as toys, etc. Unlike humans, it is difficult for humans to anticipate the movement of the robot.
[0009]
For this reason, there exists a subject that there exists a danger that a finger etc. will be pinched by a movable part. In addition, there is a problem that it is difficult to enjoy exchange of information due to fear of the danger.
[0010]
Therefore, the possibility of unexpected errors and malfunctions is higher than other mechanical devices, and accidents involving operators and neighboring users are likely to occur. Therefore, it is preferable that the robot autonomously performs avoidance processing for each error.
[0011]
[Problems to be solved by the invention]
An object of the present invention is to provide an excellent control device capable of ensuring safety during operation of a legged mobile robot having a high degree of freedom.
[0012]
A further object of the present invention is to provide an excellent control device that can avoid an accident involving an operator or a nearby user during the operation of a legged mobile robot.
[0013]
A further object of the present invention is to provide an excellent control device that can suitably prevent the danger of pinching a human finger or the like by the operation of a movable part during the operation of a legged mobile robot.
[0014]
[Means and Actions for Solving the Problems]
The present invention has been made in consideration of the above problems, and is a control device for a legged mobile robot having at least a plurality of movable legs,
A sandwiching detection unit that is disposed at a mechanical movable part of the legged mobile robot and a part of the legged mobile robot that contacts the mechanical movable part, and detects sandwiching of an object due to the operation of the movable part;
In response to detection of pinching by the pinching detection unit, an operation control unit that performs an operation of avoiding or releasing pinching;
A control device for a legged mobile robot, comprising:
[0015]
According to the control device for a legged mobile robot according to the present invention, when a pinch of a user's finger or the like is detected at a predetermined part, an operation for avoiding this is executed. In other words, the movement of the mechanical movable part prevents the danger that the robot for the purpose of exchanging information with humans and entertainment may pinch human fingers and the like by the movement. Accordingly, it is possible to provide a safe robot, and in addition, there is no fear of giving a person a feeling of fear, and there is an effect that information exchange with the robot can be enjoyed with confidence.
[0016]
Here, the pinching detection unit is disposed on at least one of the outer thigh, the thigh back, the thigh front, and the thigh inside of the leg of the legged mobile robot.
[0017]
In addition, the pinching detection unit is disposed on at least one of the inside of the shin or the front of the shin of the leg of the legged mobile robot.
[0018]
In addition, the pinching detection unit is disposed on the instep of the legged mobile robot.
[0019]
Further, the pinching detection unit is disposed on at least one of a hand side or an elbow of the hand of the legged mobile robot.
[0020]
In addition, the pinching detection unit includes a robot moving unit and a robot moving unit in a dangerous robot posture in which a hand or a finger may be pinched between the moving unit of the robot having a rotation axis and any part of the robot itself that contacts the rotating unit. It can be configured by a pressure-sensitive sensor that can detect pinching in the gap between the contact point with the robot's own part and the rotation axis.
[0021]
Further, the operation control unit may select a corresponding behavior for each posture state of the robot. For example, depending on the posture status of the robot, the operation of the robot is stopped, or the actuator is moved in a direction to release the corresponding movable part instantaneously, or the corresponding movable part actuator is defeated instantaneously. .
[0022]
In addition, the motion control unit may execute a corresponding operation every time when one foot is touched, when both feet are touched, when moving, and when stationary.
[0023]
Further, the pinching detection unit may change the force for detecting pinching for each user, such as gender age and other conditions.
[0024]
Further, the pinching detection unit may change the force for detecting pinching for each part.
[0025]
Other objects, features, and advantages of the present invention will become apparent from more detailed description based on embodiments of the present invention described later and the accompanying drawings.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0027]
FIG. 1 and FIG. 2 show a state in which the “human-shaped” or “human-shaped” legged mobile robot 100 used for carrying out the present invention is viewed from the front and the rear. . As shown in the figure, the legged mobile robot 100 includes a torso, a head, left and right upper limbs, and left and right lower limbs that perform legged movement. For example, a control unit built in the torso. (Not shown) controls the overall operation of the aircraft.
[0028]
Each of the left and right lower limbs is composed of a thigh, a knee joint, a shin, an ankle, and a foot, and is connected by a hip joint at the substantially lower end of the trunk. The left and right upper limbs are composed of an upper arm, an elbow joint, and a forearm, and are connected to the left and right side edges above the trunk by shoulder joints. The head is connected to the substantially uppermost center of the trunk by a neck joint.
[0029]
The control unit includes a controller (main control unit) that processes the drive control of each joint actuator constituting the legged mobile robot 100 and an external input from each sensor, etc., and a housing in which a power supply circuit and other peripheral devices are mounted. It is. In addition, the control unit may include a communication interface and a communication device for remote operation. The robot control system according to the present embodiment is configured such that the robot autonomously performs an avoidance process for each error, which will be described in detail later.
[0030]
FIG. 3 schematically shows the degree of freedom configuration of the legged mobile robot 100.
[0031]
The robot shown in the figure is a humanoid robot having two legs and two arms. This robot has limbs attached to the airframe, and the left and right arms have 7 degrees of freedom: shoulder joint pitch axis, shoulder joint roll axis, upper arm yaw axis, elbow joint pitch axis, forearm yaw axis, wrist roll axis, wrist pitch axis. And left and right leg portions having six degrees of freedom, that is, a hip joint yaw axis, a hip joint roll axis, a hip joint pitch axis, a knee pitch axis, an ankle pitch axis, and an ankle roll axis.
[0032]
Each of these joint degrees of freedom is actually realized by an actuator / motor. In the present embodiment, a small AC servo actuator of a gear direct connection type and a servo control system integrated into one chip and built in a motor unit is mounted. This type of AC servo actuator is disclosed in, for example, Japanese Patent Laid-Open No. 2000-299970 (Japanese Patent Application No. 11-33386) already assigned to the present applicant.
[0033]
An acceleration sensor A1 and a gyro G1 are mounted on the airframe. Also, at the four corners of the left and right soles, there are uniaxial load cells (F1 to F8) for detecting the floor reaction force in the vertical direction of the sole and infrared ranging sensors (D1 to D8) for measuring the distance to the floor, respectively. Four are attached. An acceleration sensor (A2, A3) and a gyroscope (G2, G3) are attached to the center of the left and right soles, respectively.
[0034]
The legged mobile robot according to the present embodiment is equipped with a sensor for detecting pinching of the operator's fingers and the like in addition to the sensor group for posture control, which will be described later. Give up.
[0035]
The robot control system according to the present embodiment is configured such that the robot autonomously performs avoidance processing for each error. FIG. 4 schematically shows a functional configuration of a control system applied to the legged mobile robot according to the present embodiment.
[0036]
As shown in the drawing, the legged mobile robot according to the present embodiment operates according to a command from the thinking system module 20 that is mounted on the body and controls autonomous movement, or a command from the remote control system 30 that is mounted outside the body. It has become.
[0037]
The thinking system module 20 realizes autonomous actions and operations on the aircraft.
[0038]
The remote control module 30 is configured by a computer system having a wireless LAN function, such as a personal computer (PC), and includes an input device and a PC application 31.
[0039]
The input device 32 is configured by a user input device such as a joystick, a keyboard, or a mouse, and receives an instruction to the robot based on a manual operation from the user.
[0040]
The PC application 31 is connected to the robot via a wireless LAN and exchanges data with the actual robot. The PC application 31 constantly monitors the input device signal, converts it into a command for the robot, transmits it to the robot, and can receive a reply and an error notification from the robot side.
[0041]
The gateway 19 is an in-robot object that implements a communication protocol such as TCP / IP (Transmission Control Protocol / Internet Protocol) and realizes communication (wireless or wired) with an external computer such as the remote control system 30.
[0042]
Each resource management and posture transition control module 11 of the robot distributes processing in units of resources such as a head, a body, an arm, and a leg in accordance with the sent command. In addition, regarding the posture transition, consistency is determined, and a transition from a posture inconsistent to a command to a consistent posture is also in charge.
[0043]
When the robot falls into an unknown posture, the return manager 12 returns from the unknown posture to the closest known posture and returns to a predetermined posture transition model.
[0044]
The agent group plans operations for each resource, and requests locomotion generation and motion playback according to the contents. In the illustrated example, the Agent group includes a Head Agent 13A that plans head movements, a Body Agent 13B that plans trunk movements, and a Walk Agent 13C that plans walking movements.
[0045]
The locomotion generation unit 14 is an object that generates a gait in real time in response to a request from an agent, and calculates the joint angles of the lower limbs in consideration of stabilization of the posture with respect to the generation result, Create a command value for the device.
[0046]
The motion reproducing unit 15 changes the command value of each joint angle according to the motion requested by the agent.
[0047]
The error detection unit 16 always refers to the sensor value from each device and monitors the presence or absence of an error state. Examples of the error state referred to here include a torque limiter, overcurrent detection, pinching, overturning, and stability determination. Priorities are set in advance for each error, and detection and avoidance processing is performed from the highest priority.
[0048]
In the present embodiment, the concept of a gate 17 is introduced to the locomotion generating unit 14 and the motion reproducing unit 15. While the gate 17 is open, the locomotion generation unit 14 and the motion playback unit 15 accept a command from the client, but when the gate 17 is closed, the command can be rejected. Further, the error detection unit 16 is in charge of opening / closing the gate 17. Further, even when the gate 17 is closed, the gate 17 can cope with a command from the error detection unit 16 and can realize an error avoidance operation.
[0049]
The device manager 18 communicates with each device constituting the robot such as an actuator and a sensor, and transmits a command value and receives a measurement value.
[0050]
In the basic operation of the control system shown in FIG. 4, in the remote control system 30, the input device signal is monitored by the application 31 on the PC and converted into a robot command. The created command is sent to the resource management and posture transition control system module 11 of the robot through the gateway 19 in the robot via the wireless LAN. Thereafter, a response to the command is similarly sent to the PC application 31.
[0051]
When an error is detected, all requested commands are blocked by the robot internal processing, and the influence on the operation system input does not adversely affect the robot. In addition, since the type of error that has occurred is also sent to the operation system, feedback to the input device 32 can be applied accordingly. When the error is resolved, a notification to that effect is sent to the operation system, and normal command input from the remote operation system can be resumed.
[0052]
On the other hand, commands can be transmitted from the thinking system module 20 instead of the remote control system 30 during the autonomous behavior of the robot. When an error is detected, all requested commands are blocked by robot internal processing. When the error is resolved, a notification to that effect is sent to the operation system, and normal command input from the remote operation system 30 can be resumed. Further, even when an error occurs, the thinking system module 20 can be used for processing such as arbitrary emotion expression according to the error type.
[0053]
Hereinafter, the operation of this control system will be described.
[0054]
When performing remote operation, the PC application 31 issues a command to the robot based on the input information obtained via the input device 32, and transfers this to the robot via the wireless LAN.
[0055]
Upon receiving a command from the remote control system 30 via the gateway 19, each resource management and posture transition control 11 module of the robot plans an operation for each resource by the corresponding agent 13, and determines the location according to the contents. The motion generation unit 14 or the motion playback unit 15 is requested to express the motion. The locomotion generation unit 14 or the motion playback unit 15 calls the device manager 18 and transmits command values to various devices of the corresponding robot.
[0056]
From various devices of the robot, sensor information detected when driving based on the command value is transmitted to the input device through a path opposite to the propagation of the command.
[0057]
The device manager 18 also notifies the error detection unit 16 of sensor information detected when driven based on a command value from the remote operation system 30.
[0058]
The error detection unit 16 detects errors such as a torque limiter, overcurrent detection, pinching, overturning, and stability determination based on the sensor information. When an error on the machine is detected, the locomotion generation unit 14 and the motion playback unit 15 are instructed to close the gate 17. The locomotion generation unit 14 and the motion reproduction unit 15 reject a command from the client (the remote operation system 30 or the thinking system module 20) via the gate 17 in response to the gate closing.
[0059]
In addition, the error detection unit 16 issues a command for requesting the body operation at the time of error detection to the locomotion generation unit 14 or the motion reproduction unit 15 together with an instruction to close the gate 17.
[0060]
Further, when the error detection unit 16 detects an error, the error detection unit 16 issues an error notification to each resource management and posture transition control module 11 of the robot. Each resource management and posture transition control module 11 of the robot notifies the remote operation system 30 of the error type via the gateway 19. The error type is also notified to the thinking module 20.
[0061]
The locomotion generation unit 14 or the motion playback unit 15 performs an error avoidance process according to a command from the error detection unit 16. In addition, the locomotion generating unit 14 or the motion reproducing unit 15 returns a status associated with the command execution to the error detecting unit 16.
[0062]
The error detection unit 16 determines whether or not the error has been canceled based on sensor information from various devices of the robot. When the error is canceled, the locomotion generating unit 14 and the motion reproducing unit 15 are instructed to open the gate 17. With the opening of the gate 17, the locomotion generating unit 14 and the motion reproducing unit 15 can accept a command from the client via the gate 17.
[0063]
The error detection unit 16 also notifies the resource management and posture transition control module 11 of the robot of error cancellation. Each resource management and posture transition control module 11 of the robot sends a return end notification to the remote operation system 30 via the gateway 19 and also sends a return end notification to the thinking system module 20.
[0064]
FIG. 5 shows a flowchart of the error detection processing procedure of the legged mobile robot during the walking operation.
[0065]
When the power of the legged mobile robot is turned on, hardware self-diagnosis and other initialization processes are executed (step S1).
[0066]
Next, a connection in a wireless LAN or other network form is established with a remote control system constituted by a PC or the like (step S2), and a command can be exchanged.
[0067]
When a command related to the aircraft operation is received from the remote operation system 30 (step S3), each resource management and posture transition control module 11 of the robot determines whether or not the operation content matches the state on the posture transition model of the current aircraft. It discriminate | determines (step S4).
[0068]
If the operation command does not match the state on the posture transition model, the posture that is consistent with the operation command is searched (step S5), and the posture transition is executed (step S6).
[0069]
Next, the locomotion generation unit 14 or the motion reproduction unit 15 derives each joint angle corresponding to each parameter (step length, walking cycle, direction) of the operation command input from the remote operation system 30 by a technique such as inverse kinematics. (Step S7). Then, the device manager 18 adds a control amount in consideration of posture stabilization from the values of the sole sensors (step S8), and transmits a command value to each actuator (step S9).
[0070]
When no command is input from the remote control system 30 (step S3), or after the processing of the input command is completed (step S9), the error detection unit 16 is based on the sensor information returned from the device manager 18. Then, an error is detected (step S10).
[0071]
If no error is detected, the process returns to step S3 and waits for the next command input from the remote control system 30. On the other hand, if an error is detected, the error detection unit 16 Notifies the locomotion generation unit 14 and the motion playback unit 15 of the error and stops other operations, and also notifies each resource management and posture transition control module 11 of the robot of the error (step S12). Each resource management and posture transition control module 11 of the robot notifies the error type to the higher-level remote control system.
[0072]
The error detection unit 16 has an error detection priority from the viewpoint of ensuring the operation of the machine. In this embodiment, priority is given in the order of torque limiter, overcurrent, pinching, overturn detection, and stability determination.
[0073]
The error detection unit 16 first detects a torque limiter error in each joint actuator (step S12). If an error is detected, the gain of each joint actuator, which is the location where the torque limiter is working, is reduced, each joint angle command value is changed to a measured value, and the torque is lowered (step S13).
[0074]
Next, the error detection unit 16 detects an overcurrent in each joint actuator (step S14). If an overcurrent is detected, the gain of the joint actuator that is the location where the overcurrent is generated is reduced, each joint angle command value is changed to a measured value, and the torque is reduced (step S15).
[0075]
Next, the error detection unit 16 detects pinching in each joint (step S16). When the pinching is detected, a predetermined pinching countermeasure operation is executed (step S17). In the present embodiment, when information is exchanged with a human by contact using tactile sensation, an operation for avoiding pinching of fingers and the like is performed. This will be described in detail later.
[0076]
Next, the error detection unit 16 detects whether or not the aircraft has fallen (step S18). When a fall is detected, the gain of each joint actuator is reduced and a passive posture corresponding to the direction of the fall is taken (step S19).
[0077]
Next, the error detector 16 determines the stability of the aircraft (step S20). If stability has been lost, the locomotion generating unit or the motion reproducing unit is instructed to perform the operation of stepping on the leg and raising the center of gravity so as not to fall down (step S21).
[0078]
After performing the process according to the error detected in any of steps S13, S15, S17, S19, or S21, or if no error is detected, it is determined whether or not the error has been resolved (step S22). .
[0079]
If the error has not been resolved, the process returns to step S10, and the above-described error detection process is repeatedly executed.
[0080]
If the error is resolved, each resource management and posture transition control module 11 of the robot searches for the known posture closest to the current unknown posture (step S23), and executes the posture transition (step S23). S24), the process returns to step S3 and waits for the input of the next command from the remote control system.
[0081]
In step S17 of the flowchart shown in FIG. 5, when a pinch of a user's finger or the like is detected at a predetermined part, an operation for avoiding this is executed. In other words, the movement of the mechanical movable part prevents the danger that the robot for the purpose of exchanging information with humans and entertainment may pinch human fingers and the like by the movement.
[0082]
The contact point between the robot movable part and the robot's own part when the robot is in a dangerous robot posture where a hand or a finger can be caught between the robot's movable part having a rotation axis and any part of the robot that contacts the robot's own part A pressure-sensitive sensor capable of detecting pinching is provided as a pinching sensor in a gap (not limited to 12 mm or less) between the rotating shaft and the rotating shaft.
[0083]
As the pressure-sensitive sensor, for example, a sheet-type or button-type structure can be adopted. Alternatively, a torque limiter mechanism is provided on the rotating shaft. In addition, the robot housing is provided with a material having a shape and a friction characteristic that is flexible and does not add an object to be sandwiched such as a hand or a finger due to friction.
[0084]
6 and 7 show examples of arrangement of pinching sensors in each part of the legged mobile robot 100 shown in FIGS. The table below summarizes the location of the pinch sensor.
[0085]
[Table 1]

[0086]
As shown in FIGS. 6 and 7, pinching sensors are arranged at 18 portions where it is estimated that there is a risk of pinching on the airframe.
[0087]
In order to quantify the pinching conditions for the pinching sensor to detect pinching, the present inventors conducted a survey on the limit force of pain that can withstand pinching on human fingers and nails. The table below summarizes the results of this marginal force test. However, there were two types of objects to push the finger: a stainless steel φ12 mm cylinder and an aluminum flat plate, and the measurement points were four on the fingertip abdomen, nail, first joint nail side, and fingertip side of the index finger.
[0088]
[Table 2]

[0089]
As a result of the limit force test, it was confirmed that the minimum load under the sandwiching condition was 2 kg. Based on this, in the present embodiment, the pressure sensitive sensed by the pinching sensor is set to 2 kg.
[0090]
The pinching sensor is, for example, a sheet-like pressure sensor (feeling the force on the entire sheet surface), thereby covering a wide range of the pinching portion, thereby improving safety. The attachment range of the pressure sensor is a clearance between the contact point between the robot movable portion and the robot's own part and the rotation axis.
[0091]
If the pinching force of a person's hand or finger exceeds 2 kg, the robot's movement is stopped, the movement of the pinched area is instantaneously opened depending on the condition of each part, the force is instantaneously defeated, the robot's posture Select the corresponding behavior for each situation. As a result, a secondary disaster to a person caused by the robot breaking its posture and falling is avoided.
[0092]
In addition, a torque / limiter mechanism is provided on the rotating shaft, which distributes the force to pinch the hand or fingers to the robot casing surface to reduce the danger. It shall be provided with a material that has a shape and frictional characteristics that cannot be inserted. For safety reasons, the direction of exiting may be in front or behind, but it is necessary to avoid being taken in and taken together when the robot falls. It is very dangerous if the aircraft falls while holding your finger.
[0093]
In the present embodiment, an adaptive control method is assigned as a coping operation of the robot when the pinching is detected for each part. In addition, the sensor pressure and torque limit values are set to appropriate amounts for each part. When pinching is detected by the sensor output, the operation of the corresponding movable part actuator is stopped instantaneously, the torque or force of the actuator is reduced, and the actuator is moved in a direction to open the corresponding movable part.
[0094]
In this embodiment, a robot adaptive control method is assigned as a robot coping operation when pinching is detected for each posture state of the robot. When pinching is detected by the sensor output, the operation of the corresponding movable part actuator is instantaneously stopped, the torque or force of the actuator is reduced, the posture is largely destroyed, and the secondary disaster caused by the fall is avoided, and the corresponding movable part Move the actuator in the direction to release.
[0095]
In particular, by changing the response method after detection of the pinch sensor according to the posture and posture of the legs, the torque or force of the actuator is reduced, and the secondary disaster caused by the posture being largely collapsed and falling is avoided. For example, the corresponding operation is executed every time when one foot is touched, when both feet are touched, when moving, and when still.
[0096]
FIG. 8 shows an operation procedure of the adaptive posture / behavior by the pinching sensor for the leg in the form of a flowchart. Such an operation procedure is executed by the locomotion generation unit 14 or the motion reproduction unit 15 in response to an error notification from the error detection unit 16. As shown in the figure, the adaptation method is selected depending on whether or not the foot is in contact with the ground, whether it is walking, or is stopped.
[0097]
When the posture state of the robot when the pinch sensor is detected is dynamic grounding, the grounding state is further confirmed (step S1).
[0098]
In the case of both-foot contact, it moves so as to open the pinched shaft, balances with the other leg so as not to fall (step S2), and shifts to a stable posture.
[0099]
Also, in the case of one-leg grounding, it moves so as to release the pinched shaft, and the other leg that is not grounded is grounded and adaptively controlled to achieve balance (step S3), so that a stable posture is taken with both legs. To do.
[0100]
Here, in the case of failure to balance in step S2 or S3, safety is ensured by the aircraft falling down in accordance with safe overturning control (step S4).
[0101]
On the other hand, if the posture of the robot when the pinch sensor is detected is static grounding, both one foot and both feet are grounded (step S5), and the pinched axis is Open Thus, the original posture is returned (step S6), and the stable posture is maintained.
[0102]
Here, when it is not possible to return to the original posture, safety is ensured by the aircraft falling down in accordance with the safe fall control (step S7).
[0103]
In step S4 or S7, when the robot falls due to the operation of avoiding pinching, an adaptive control method of the falling posture and the falling motion is assigned in order to prevent harm to people and the surroundings.
[0104]
Moreover, you may make it change the force which a pinch sensor detects for every user, such as man and woman age and other conditions. User-specific conditions and the like are recognized visually or by voice.
[0105]
In this case, the values detected by the pinching sensor applied according to the size of the hand such as the user's physique and the strength are classified into levels so that the user can take appropriate measures. For example, the modes (ABC...) Are divided in advance as shown in the table below. In the case of small children and women, the magnitude of the force detected by the sensor is reduced to increase safety. In this case, the application level is also divided into cases (gain value / operation speed adjustment, etc.).
[0106]
[Table 3]

[0107]
Moreover, you may make it change the force detected with the pinching sensor for every site | part. Further, the force to be detected may be changed depending on the sandwiching shape or the sandwiched moment position.
[0108]
[Supplement]
The present invention has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiments without departing from the gist of the present invention.
[0109]
The gist of the present invention is not necessarily limited to a product called a “robot”. That is, as long as it is a mechanical device that performs a movement resembling human movement using an electrical or magnetic action, the present invention similarly applies to products belonging to other industrial fields such as toys. Can be applied.
[0110]
In short, the present invention has been disclosed in the form of exemplification, and the description of the present specification should not be interpreted in a limited manner. In order to determine the gist of the present invention, the claims section described at the beginning should be considered.
[0111]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide an excellent control device capable of ensuring safety during operation by a legged mobile robot having a high degree of freedom.
[0112]
Further, according to the present invention, it is possible to provide an excellent control device that can avoid an accident involving an operator or a nearby user during work of a legged mobile robot.
[0113]
Further, according to the present invention, it is possible to provide an excellent control device that can suitably prevent the danger of pinching a human finger or the like by the operation of the movable part during the operation of the legged mobile robot.
[0114]
According to the control device for a legged mobile robot according to the present invention, it is possible to eliminate the risk of a hand or a finger being caught when information is exchanged with an operator through contact using a tactile sensation. Therefore, it is possible to provide a safe robot, and in addition, there is no effect of giving fear to people, and there is an effect that information exchange with the robot can be enjoyed with peace of mind.
[Brief description of the drawings]
FIG. 1 is a diagram showing a state in which a legged mobile robot 100 used for carrying out the present invention is viewed from the front.
FIG. 2 is a view showing a state in which a legged mobile robot 100 used for carrying out the present invention is viewed from the rear.
FIG. 3 is a diagram schematically showing the configuration of the degree of freedom of the legged mobile robot 100. FIG.
FIG. 4 is a diagram schematically showing a functional configuration of a control system applied to a legged mobile robot.
FIG. 5 is a flowchart showing a procedure of error detection processing of a legged mobile robot during a walking operation.
6 is a diagram showing an example of the arrangement of pinching sensors in each part of the legged mobile robot 100. FIG.
FIG. 7 is a diagram illustrating an arrangement example of a pinch sensor in each part of the legged mobile robot 100. FIG.
FIG. 8 is a flowchart showing an operation procedure of an adaptive posture / behavior by a pinching sensor for a leg.
[Explanation of symbols]
11 ... Management of each resource of robot and posture transition control module
12 ... Return manager
13 ... Agent
14 ... Locomotion generator
15 ... Motion playback part
16: Error detection unit
17 ... Gate
18 ... Device Manager
19 ... Gateway
20 ... Thinking module
30 ... Remote control system
31 ... PC application
32 ... Input device

Claims (7)

A control device for a legged mobile robot having two movable legs,
A pinching detection unit for detecting pinching of an object due to an operation of a movable unit having a degree of freedom around the rotation axis of the legged mobile robot;
In response to detection of pinching by the pinching detection unit, an operation control unit that performs an operation of avoiding or releasing pinching;
With
The pinching detection unit is disposed in a part that is estimated to be at risk of pinching an object by operation of the movable part, or a movable part that is estimated to be at risk of pinching of an object by operating,
The operation control section, upon detecting a pinching of an object by the operation of the movable part contained in the leg, when the sandwiched object in one of the legs of the two movable legs and dynamic ground on two feet while The robot's posture is stabilized using one leg, and in the case of dynamic grounding with one foot, the free leg is grounded and the posture of the robot is stabilized using both feet, and in the case of static grounding with both feet or one foot, the current supporting leg is used. To stabilize the posture of the robot using
A control device for a legged mobile robot. The pinching detection unit is disposed on at least one of the outer thigh, the back thigh, the front thigh, and the thigh inside the leg of the legged mobile robot.
The control device for a legged mobile robot according to claim 1. The pinching detection unit is disposed on at least one of the shin inner side or the shin front surface of the leg part of the legged mobile robot,
The control device for a legged mobile robot according to claim 1. The pinching detection unit is disposed on the instep of the legged mobile robot.
The control device for a legged mobile robot according to claim 1. The pinching detection unit is disposed on at least one of a hand side of the legged mobile robot or an elbow of the hand,
The control device for a legged mobile robot according to claim 1. The pinching detection unit is configured such that the robot movable unit and the robot's own part are located at a site where it is estimated that there is a risk of object pinching due to the movement of the movable unit having a degree of freedom around the rotation axis of the legged mobile robot. Consists of a pressure-sensitive sensor that can detect pinching in the gap between the contact point and the rotating shaft,
The control device for a legged mobile robot according to claim 1. The operation control unit stops the operation of the movable part actuator corresponding to the part where the pinch detection unit detects the object pinching, reduces the torque or force of the actuator, and moves the actuator in a direction to open the corresponding movable part. At the same time, when the pinching detection unit detects the pinching of the object with the movable leg, the posture state and the grounding state of the legged mobile robot are further confirmed. Move to open the axis that sandwiches the object of one leg and balance with the other leg so that it does not fall over, and open the axis that sandwiched the object of one leg that sandwiched the object when one leg touched in a dynamic posture Make sure that the other leg that is not touching the ground is grounded and balanced with both feet. Returns to the original position even in the ground state to open an axis across the object of one of the legs sandwiching an object,
The control device for a legged mobile robot according to claim 1.

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