JP3435081B2 - Reconfigurable Space Manipulator System for Space - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reconfigurable multi-limb manipulator system for a space in which a plurality of arms are connected to each other according to a work form to form a manipulator, and more specifically, to perform work in space. Small multi-limb manipulator (extension length of several tens of cm to 3 m)
The present invention relates to a reconfigurable multi-limb manipulator system for space that can be configured as a system.

[0002]

2. Description of the Related Art Conventionally, unlike industrial robots, space robots have been developed as robots for work in space. Such space robots include an on-orbit robot that performs various services of a spacecraft flying in a satellite orbit and an exploration robot that performs various measurements on the surface of the moon and planets. Space robots are expected to perform various tasks in future missions such as support for unmanned space activities, support for manned space activities, and space exploration in future space activities. The space robots developed so far include the following.

The Shuttle for space shuttles as shown in FIG. 1 are those already developed or under development.
le-RMS (Canada) robot arm 100, FIG.
JEMRMS (Japan
ese Experimental Module Remote Manipulator System
: Japan) etc. In FIG. 2, 201 is a supply section pressurizing section, 202 is a manipulator, 203 is a precision work robot arm, 204 is a supply section exposing section, 205 is an airlock, 206 is an exposing section, and 207 is a pressurizing section. In such a robot arm, a dedicated gripping part (10
cm), it is used to move objects in space and capture statically fixed and floating satellites.

Further, as shown in FIG. 3, SSRMS (Space Station Remoter Manipulator) for space station is used.
System; USA / Canada), such as crossing a dedicated moving port or moving on a rail to perform the above work. In FIG. 3, 301 is a space station, 302 is a mobile transporter, 303 is a mobile remote service base system, 304
Is a space station remote manipulator. These are systems with a crane-type manipulator of 10 m scale.

As a system having a slightly small 2-5 m scale single-arm / multi-arm manipulator, as shown in FIG. 4, an arm hand camera 403 and an arm monitor camera of an "ETS-VII" manipulator (Japan). Four
Robot arm 401 having 02, or reference numeral 3 in FIG.
As shown in 05, SPDM for space station
(Canada) robot arm, JEMRMS child arm as shown by reference numeral 203 in FIG. These are intended to handle small-sized operating objects provided with a dedicated gripping part (several to several tens of cm).

[0006] Among those that have been studied and tested so far, there are outboard exposure spaces that astronauts should perform (hereinafter EV
Although it has been developed with the aim of substituting for work (A), FTS (Flight-Telerobotic) has been discontinued.
-Servicer: USA) and a non-manipulator type robot Charlotte (US) that was developed with the aim of performing routine work related to space experiments in pressurized space (hereinafter referred to as IVA) onboard )and so on.

[0007] Furthermore, at a more basic research level, the robot component can be exchanged and reconfigured during flight in a satellite orbit, and the operation position can be reached while avoiding obstacles. There are a snake type with multiple degrees of freedom, and a human type suitable for IVA work and EVA work that is designed to sufficiently secure the workability of crew members.

[0008]

By the way, one of the important targets for future research on space robots is a robot that substitutes a part of IVA work and EVA work currently performed by crew members in a manned system. It is a robot that works with unmanned systems such as on-orbit work machines and solar power generation platforms. With the IVA robot, the work of monitoring and turning on / off the meter of the space experiment device,
It is a robot that performs work such as replacement of experimental sample cassettes. With the EVA robot, the work clearance (precision to several mm) with a finer work precision (precision to several mm) is provided from the function provision of the work of exchanging objects to be operated (precision of 10 mm or more) and the work assistance of EVA-Crew. Since the space area required for the robot to perform its work is small, it is desirable to carry out maintenance / inspection, space experiments, assembly / disassembly, and other such work / support work inside / outside the ship.

Further, it is desired that the work of the unmanned platform can be performed such as assembling / wiring / adjusting / disassembling the system and system maintenance work. As a robot for these tasks, the functions that should be provided are the movement function for expanding the work range, the reconfiguration function, the multi-arm operation function,
It is a robot arm with improved work ability, such as a hand (dexterous finger) function for high precision work.

However, until now, in order to realize a practically useful and effective space robot system, there has been no specific construction technique that satisfies the requirements from the following multifaceted viewpoints. In designing a robot system, the system penalty on the user side due to the introduction of a robot is minimized (cost reduction, weight reduction, storability, failure resistance, reliability,
Operability / simplification of special robot-specific interface) to improve operability (safety / certainty / efficiency / easiness)
It is important to make a comprehensive system design with necessary and possible levels of dexterity and multi-functionality without sacrificing this.

The technology of the robot system that has been developed so far includes a function of crossing a dedicated port to expand an operation range, a snake function by a multi-degree-of-freedom serial link, a reconfiguration function / repair function by a module configuration, and the like. However, it is not possible to construct a concrete and effective space robot system with such individual element technologies.

Next, the problems of the multifaceted problem will be described with reference to specific examples. For example, with an EVA robot, EVA-
In order to give a force equivalent to that of Crew (outboard worker), the joint torque needs to be several tens Nm. The joint part
In the current motor technology, the diameter is 10 cm or more and the weight is up to several kg. As a manipulator, the weight is over 50 kg and the length is over 1 m, and a wide working clearance is required. Workability is further degraded with dual arms.

For example, in a conventional robot system, if an attempt is made to have a function of crossing a dedicated port or the like in order to expand the work range, interface connection of the dedicated port (needs 100 or more) and a base part. The mechanism becomes large-scale, and the burden on the spacecraft side becomes extremely large.

For example, the hand precision of a conventional space robot is about 5 to 10 mm, but in order to have an absolute position reproduction precision of 2 to 3 mm in order to perform a finer work, a wide temperature range is required. If it is a manipulator for space that is premised on the operation and preservation of, in that case, the arm length must be shortened to about several tens of cm, or an active thermal control system must be introduced at the joint part.

In addition, for example, redundant multiple winding joints are used to improve reliability, and drive amplifier "N" is used.
There is also a method of adopting “out of M (N <M) redundancy method” (this is a redundancy method of driving N motors while switching M amplifiers that can be substituted), but the complication of elements and weight / size This results in a decrease in functionality and an increase in operational complexity.

[0016] Further, even if an attempt is made to replace the on-orbit and improve the reliability and operability by using a modular structure capable of exchanging joints and the like, if not properly designed, there are many coupling mechanism interfaces for modularization. Becomes more complicated.

Similarly, if the manipulator has multiple degrees of freedom (more than 7 degrees of freedom) in order to improve workability and reliability, it causes an increase in weight and cost, and further, a single failure occurs. However, most of the functions may be lost depending on the failure mode, and it cannot be generally said that the system can be a degenerate function maintenance system (a system in which as many system functions as possible remain according to the occurrence of a failure).

In other words, if the robot is simply designed in accordance with the required functional requirements in order to improve general-purpose work ability and reliability, a complicated system is inevitable, resulting in higher price and lower reliability. There is a problem in that the size and weight of the robot increase, and as a result, an effective system configuration cannot be obtained.

Further, since the development of a space robot requires a high development cost and a development period of several years, the technology accumulated by developing and operating one robot system is as much as possible in the next robot. It is important to be able to inherit it for development, and robots in space systems that are operated for a long time such as 10 years have the potential to incorporate the evolving robot-related elemental technologies and update the system. It is desirable that the system be

Although it is expected that the space robot will be comprehensively designed so as to satisfy such a point of view, no one that comprehensively satisfies such a problem has been presented so far.

Therefore, an object of the present invention is to provide a reconfigurable multi-limb manipulator system for space which can be constructed as a small multi-limb manipulator system for working in space.

[0022]

In order to achieve such an object, the reconfigurable multi-limb manipulator system for space according to the present invention has the following basic concept for constructing a system. (2) Equipped with a simple, lightweight, microscopic joint that takes advantage of the universe's low gravity, and a small, lightweight arm that uses internal force operation, and (3) Flexibility. (4) Equipped with smart perception for automatic machine operation and interactive operation,
(5) Equipped with an end effector for movement, reconfiguration, and operation, and (6) Reduces the wire harness (weight reduction) by performing distributed control using a high-performance embedded computing and high-speed serial internal communication bus. (7) Incorporate elemental technologies such as ensuring operability with an onboard monitoring system. (8) Regarding high reliability, since it is difficult to achieve both dexterity and redundancy, a manipulator system is configured by a plurality of the same manipulators configured by simple elements without redundancy, and a plurality of arms are provided. We decided to secure system reliability by reconfiguring.

Therefore, the reconfigurable space multi-limb manipulator system according to the present invention is a reconfigurable space multi-limb manipulator system for performing various space operations under low gravity. As a feature of the system, a system is basically composed of a plurality of manipulators (arms) having the same structure and system components. One arm functions as one robot, and by being connected to each other, its shape is changed to function as one or a plurality of robots.

Due to such a feature, it is required to improve the reliability by constructing the system with a plurality of arms having a simple structure without using a lot of internal redundancy in the inside of a single arm. Can meet. Furthermore, for a system already deployed in space, a high-performance arm equipped with a common (backward compatible) interface is replenished from the ground, replaced and added to maintain the overall system and improve its performance. be able to.

Further, since the development of a space robot requires a high development cost and a development period of several years, the technology accumulated by developing and operating one robot system should be applied to the next robot as much as possible. It is important to be able to inherit, and robots in space systems that will be operated for a long time such as 10 years are systems that have the potential to update the system by incorporating evolving robot-related element technologies. Is desirable. According to the system configuration of the present invention, the cooperative use of a plurality of robots for performing work and mutual monitoring is particularly effective in the universe in which humans are heavily burdened. The system according to the invention facilitates this.

For example, in order to improve reliability, redundant multi-winding joints are used, or a drive amplifier "N out of M (N <M) redundant system" (replaceable M There is a method of adopting a redundant system in which N motors are driven while switching amplifiers), but this complicates the system components and increases the weight and size, resulting in deterioration of functionality and complication of operation. In addition, even if joints and other components are designed to be interchangeable, and if they are not properly designed even if they are exchanged on orbit to improve reliability and operability, the number of coupling mechanism interfaces for modularization increases, and It gets complicated. Similarly, if the manipulator has multiple degrees of freedom (more than 7 degrees of freedom) in order to improve workability and reliability, it causes an increase in weight and an increase in price. Since most of the functions may be lost, it cannot be generally said that the system can be a degenerate function maintaining system (a system in which as many system functions as possible remain according to the occurrence of a failure). In other words, if a robot is simply designed according to functional requirements in an attempt to improve general-purpose work ability and reliability, a complicated system will result, resulting in higher cost, lower reliability, and increased robot size and weight. , And as a result, it does not become an effective system. These are solved by the system configuration of the present invention having the above-mentioned features.

A second feature of the reconfigurable multi-limb manipulator system for space according to the present invention is that the boom of the arm is equipped with a distributed computer having a high-speed serial communication function, and cooperative control of the entire robot system is performed. And calculate the process of monitoring other manipulators,
Perform processing calculations for high-speed communication lines. This distributed computer is a computer that is configured as a multi-arm manipulator and changes its function according to the form of the robot to perform the central calculation of the robot, or depending on the form, perception (image, vibration, force, etc.) ) Data processing and data relay computer.

The third feature of the reconfigurable multi-limb manipulator system for space according to the present invention is that, as a third feature, operating arms having basically one degree of freedom (driven by one motor) are provided at both ends of each arm. It is equipped with an end effector having an electrical coupling connector with this end effector.
It is assumed to have a function of operating the operation target. Further, this end effector can be electrically and mechanically coupled by gripping a dedicated port prepared on a spacecraft or a robot system. The number of lines for electrical coupling is extremely reduced by using a high speed communication line processed by a distributed computer. Specifically, the number is reduced to about 10 to 30.

By having such features, reconfiguration of the robot system and walking (walking) on the dedicated port can be easily realized. Furthermore, for example, it is possible to realize the autonomy of the robot control system required for walking on the spacecraft in the process of assembly without a moving port.

For example, if a conventional robot system is to have a function of crossing a dedicated port or the like in order to expand the work range, the interface connection of the dedicated port (100 or more conventionally) or the base mechanism is required. It will be a huge one, and the burden on the spacecraft will be extremely heavy. On the other hand, future space robots will have various space experiments such as infrared cameras, 3D cameras, high-magnification cameras, and special sensor heads such as vibrometers for in-orbit inspection work. It is expected to equip the tip with an experimental head for life systems, etc., but as mentioned above, such an equipment (payload) system also has the above-mentioned common interface to simplify the entire robot. You can

The combination technology of the "distributed computer" and the "wiring-saving high-speed internal communication system" according to the present invention is basically used in recent FA (Factory Automation) systems and research robots. As a basis of the configuration, first, a wiring-saving system is adopted in order to easily realize the reconfiguration and the walking movement system. Furthermore,
In order to realize the function of moving between multiple docked spacecrafts, walking over dead spacecrafts and spacecraft in the process of assembly, the purpose is to pass through a place that is not a dedicated movement port (for example, handrail or truss). However, in the present invention, this function is realized by making each robot autonomous by the distributed computers distributed inside the robot arm. In this case, a built-in battery is indispensable, and in some cases it is necessary to prepare air link communication in the vicinity, but this is a simple additional function and can be realized by a known technique.

A fourth feature of the reconfigurable space type multi-limb manipulator system according to the present invention is that the joint of the arm is provided with a small motor and a drive circuit with an output margin. The joint of this arm is a small joint with a small steady force (continuous output) but a large instantaneous force (up to several seconds), so that it can exhibit a relatively large operating force in a short time despite its small size. It is configured. With this feature, it is possible to reduce the size and weight of the robot, reduce the work clearance, and achieve good workability.

A fifth feature of the reconfigurable multi-limb manipulator system for space according to the present invention is that an operation target having a dedicated interface for a robot can be operated by an internal force operation of an end effector finger. Is designed to. This end effector's fingers prevent the force torque generated during operation from being transmitted to the arm.This feature enables safe, reliable, efficient and easy manipulator operation without imposing a burden on the payload side. can do.

This is, for example, for an EVA robot.
-To give a force equivalent to that of Crew (outboard worker), the joint torque needs to be several 10 Nm, and the joint has a diameter of several tens of cm and a few kg in the current motor technology. Is weight ~ 50 kg, length ~
It becomes a little over 1 m, requires a wide work clearance, and further deteriorates workability with single and double arms. At the current technical level, for example, in robot technology including the ground, the function equivalent to "fingers" is immature, and when reliable work such as work in space is required, normally,
Although the end effector and the operation article have a dedicated interface, the present invention is further improved to have a system configuration in which a relatively small work expected in space is efficiently performed by a small arm.

A sixth feature of the reconfigurable space type multi-limb manipulator system according to the present invention is that the end effector is provided with a small camera having a wide depth of field (several mm to several m). The dedicated ports and dedicated controls are equipped with small markers for measurement (10 mm square). With such a feature, it is possible to monitor and observe a wide range of peripheral area, and it is possible to measure the position and orientation of a relative object with a relative 6 degrees of freedom to a close range.

For example, the hand precision of a conventional space robot is about 5 to 10 mm, but in order to perform finer work, it is necessary to have an absolute position reproduction precision of 2 to 3 mm. . In a space manipulator which is premised on operation and storage in a wide temperature range, it is unavoidable to shorten the arm length to about several tens of cm or introduce an active thermal control system into the joint. For this reason, in the conventional technique, a marker of several cm square apart from the contact portion is required in order to measure the relative position / orientation by imaging with a camera 10 to 30 cm apart. According to the two requirements of peripheral observation and marker measurement, the end effector is equipped with a small camera with a wide depth of field, and a dedicated port or dedicated operation object has a small measuring marker (~ 10 mm).
It is realized by the system configuration of a small robot with a manipulator arm.

Using the reconfigurable space multi-limb manipulator system of the present invention having various characteristics as described above,
When the system is constructed, the manipulator system of the robot arm can be a multi-limb manipulator system configuration with excellent flexibility and practicality.

With the reconfigurable multi-limb manipulator system for space of the present invention, for example, a two-limb manipulator
When configuring the system, an arm that has a hollow boom that connects multiple joints with connection ports at both ends,
One-limb manipulator arm having an end effector having an operating finger portion and an electrical coupling portion and provided at both ends of the arm, and a distributed control computer having a communication function and a joint control function inside the hollow boom. The two-limb type manipulator arm is arbitrarily combined at the position of the coupling port to form a two-limb type manipulator system. Here, since the parts / modules of the system element are made common and simple, the cost can be reduced.

Further, according to the reconfigurable space type multi-limb manipulator system of the present invention, the ability to cope with various works and the walking movement inside and outside the vessel can be achieved by the arbitrary configuration of the manipulator by the reconfiguration of the lightweight arm. Since the functions will be provided, it is possible to configure a manipulator system that has the necessary functions as a practical space robot (low user burden for introduction, excellent operability, working ability as a robot). .

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, modes for carrying out the present invention will be specifically described with reference to the drawings. A system configuration example in the case of configuring the reconfigurable multi-limb manipulator system for space according to the present invention will be described with respect to an outline of the system and each element of various system configurations. As a design example of the manipulator system configuration here, a configuration example of a three-limb type manipulator system (with three manipulator arms) is shown in FIG. 5, and a configuration example of a two-limb type manipulator system (with two manipulator arms). As shown in FIG.

Since these systems have the same system configuration, detailed examples of system elements will be described by taking the system configuration of the three-limb type manipulator system as an example. As shown in FIG. 5, the arm 50 of one manipulator has a total length of, for example, 80 cm, and has a joint having two degrees of freedom at the center and at both ends (a joint rotating in the axial direction and a joint rotating in the direction perpendicular to the axis). It is configured as a link mechanism including a joint part 51 that is a combination of the above, and has a so-called 6-degree-of-freedom serial link structure. At both ends of the arm, as will be described later, an end effector 52 including operating fingers, a camera, a connector, etc.
Are equipped with. Further, in the hollow boom 53 that constitutes the link mechanism of the arm 50, a joint drive circuit, a wire harness, and distributed control that performs joint control, joint cooperative control of the entire robot, operation monitoring, system management, communication interface, and the like. A calculator is placed. In FIGS. 5 and 6, 57 is a spacecraft, and 56 is a coupling port provided in the spacecraft.

The end effectors 52 provided at both ends of the arm 50 have a plurality of operating fingers and connector portions for mechanical structural connection for walking movement / reconstruction, electrical connection, and various operations. And equipped with CCD camera. In addition, a wire harness composed of a power supply line and a high-speed serial communication bus penetrates into the boom 53 of the arm 50, and the end effectors 52 at both ends are connected to the outside (coupling at a coupling port). Is equipped with a wire harness.

In the robot central portion 54, which is the base of the arm 50, there is a coupling port 55 for coupling with the end effector 52 of each arm 50 and allowing the power line / high-speed serial communication bus to penetrate through the arm 50. It is installed in three places. Further, although not shown, a plurality of vibration sensors for monitoring the operation of the robot arm are attached to various parts of the entire robot arm. The signal detected by the vibration sensor is input to the distributed control computer provided in the hollow boom.

Further, according to this manipulator system, as will be described later, a plurality of arms 5 of the manipulator are provided.
With the control of 0, walking movement while grasping an object,
Multi-arm work in combined and separated states, multiple arms 5
It can be applied to a variety of tasks such as the expansion of the stride in the serial connection state of 0 and the snake action to avoid obstacles, and the powerful force work in the parallel connection state of the three arms 50. Function can be realized. In addition, each has a port for moving and reconfiguring the link mechanism at both ends, and by separately preparing a non-movable boom with a straight line / curve and a boom with a passive joint, it is possible to expand the stride and reach the snake movement. It can be easily reconfigured into a robot arm form suitable for each work, such as expansion of the distance.

FIG. 6 is a diagram showing a configuration example of a two-limb type manipulator system. When two manipulator arms are combined, as shown in FIG. 6 (A), the two manipulator arms are combined and combined in a T-shape, and connected to the connection port 61b provided in the joint portion at the center of the first manipulator arm 61. On the other hand, the second manipulator arm 62
One end effector 62 provided at both ends of the
A is combined to form the system. This makes the first
It functions as a robot arm having 11 degrees of freedom between the end effector 61a provided at the end of the second manipulator arm 61 and the end effector 62b provided at the other end of the second manipulator arm 62. Will be done.

Further, as shown in FIG. 6 (B), two arms may be combined in series and coupled. In this case, the coupling port 61b provided at the joint portion at one end of the first manipulator arm 61.
On the other hand, an end effector 62a provided at the other end of the second manipulator arm 62 is coupled to form a system. As a result, the end effector 6 at the end of the first manipulator arm 61 is
Between 1a and the end effector 62b at the end of the second manipulator arm 62, it can be used as a robot arm having 13 degrees of freedom.

FIGS. 7A and 7B are block diagrams showing the circuit configuration of the electric system provided inside the boom of the arm of the manipulator. As shown in FIG. 7A, in one manipulator arm composed of the basic elements of the end effector section 71, the joint section 72 and the boom section 73, the wire harness 63, A joint drive circuit 64, a distributed control computer 65, and a communication processing circuit 66 are provided. The distributed control computer 65 performs joint control, joint coordinate control of the entire robot, operation monitoring, system management, and data processing such as communication interface processing. A joint motor 74 is embedded in the joint portions 72 provided at both ends of the boom portion 73 constituting the arm link mechanism, and the joint motor 74 is driven by the joint drive circuit 64 according to the joint control program by the distributed control computer 65. Drive controlled. The joint 72
Is composed of a pair of a first joint motor that rotates in the axial direction and a second joint motor that rotates in a direction perpendicular to the axial direction, and each joint motor is jointed according to a joint control program by the distributed control computer 65. Drive control is performed by the drive circuit 64.

The end effector section 71 has a CCD camera section 67 having a wide depth of field by an optical system lens assembly, and a connector section 68 for electrical coupling when used in a system configuration coupled with a port. Is provided. Further, the end effector section 71 is provided with a plurality of operating fingers (not shown) for performing various operations and a drive motor 69 of a drive mechanism thereof. The control of these operating fingers is drive-controlled via a drive control circuit in accordance with a drive control program by the distributed control computer 65 provided in the boom portion 73, similarly to the joint motor.

These connectors 68 are connected to the wire harness 63, and the wire harness 63 is composed of a power supply line and a data bus wiring in which the number of signal wirings is reduced by a high-speed serial communication bus. This wire harness 6
3 is connected to the communication processing circuit 66, and is provided so as to penetrate between the manipulators.

The CCD camera section 67 is shown in FIG.
As shown in, the CCD unit 76, the pre-processing / A / D conversion unit 7
7. The focus control lens drive control unit 78 is provided, and the video signal from the camera body unit 76 is preprocessed / A /
In the D conversion unit 77, digitized and image processed,
The video signal is passed through the communication processing circuit to the wire harness 6
3 is transmitted via the high-speed serial communication bus.

Next, an operation example of the manipulator system having a system configuration in which a plurality of manipulator arms having such a configuration are coupled will be described. Figure 8
10A to 10C are views illustrating modes in various work modes in the case where three manipulator arms having six degrees of freedom are combined to form a manipulator system. Here, one manipulator arm has six joints and has six degrees of freedom. A manipulator system is constructed by using three of these. The work mode shown in FIGS. 8 and 9 has three manipulator arms (81, 82,
83) are linked together. The movement mode is shown in Fig. 8.
This mode is used in the form shown in FIG. It travels using three arms as three legs to move to the work place. In this case, for example, while holding the material with one arm 82, the remaining arms 81 and 83 are held.
It can also be used to walk using two legs. There is a work mode that is used to transfer goods.

The one-handed work mode is a mode used in the form as shown in FIG. One arm 81 is fixed to the base as a foot, and one arm 83 is used for (one-handed) work, and the other arm 82 is one arm by the CCD camera provided in the end effector section. 83
One-handed work is monitored by. This allows the work to proceed while monitoring.

The form of the work mode shown in FIG. 9A is a dual arm work mode. In the work mode used in such a form, while one arm 81 is fixed as a foot to the base, the work of moving the material is performed by the two arms (two arms) of the arm 82 and the arm 83. In other words, the work object is grasped and moved by the two arms, or one end of the operation object is fixed by one arm, and the other end of the operation object is positioned by the other arm. This is a work mode in which operation is performed with multiple arms.

In the work mode mode of the high output mode, the mode as shown in FIG. 9B is used. In this case, for work requiring a stable and large force, two arms of the arm 81 and the arm 83 are firmly fixed to the base as legs and the work is performed by the other arm 82. This is a work mode when performing work that requires a strong force. For example, it is a form of a work mode in the case of performing a high output work such as insertion and removal of a connector.

Further, this is an example of the system configuration of the three-limb type manipulator system. The form of the work mode coupled in series is three arms 8 as shown in FIG. 10 (A).
In this mode, 1, 82, 83 are connected in series and used. That is, for inspection work and operation at a remote place, three arms are connected in series and used as one long arm. In this case, for example, the arm 81 and the arm 82
The joint is used by fixing it in a braked state so that a strong tip force can be utilized only by the joint of the arm 83. This work mode is suitable for remote inspection work and operations. In this work mode, the inspection work is performed by the CCD camera provided on the end effector portion of the one end arm, and the work is performed by the operation finger provided on the end effector portion of the one end arm. To do.

Further, as another form of the work mode of the system configuration coupled in series, there is, for example, a separation cooperation mode as shown in FIG. 10 (B). In the work mode of separation and cooperation, the work by the two arms of the arm 81 and the arm 82 connected in series and the work by the single arm 83 work in cooperation with each other. This is a work mode that can be suitably used for the delivery and assembly of parts.

FIG. 11 is a diagram for explaining an example of the operation of the multi-degree-of-freedom serial link manipulator depending on the degree of freedom of the tip. As described above, in the form of the work mode in which a plurality of arms are connected in series to configure the system, many joints of the series arms can obtain a sufficient degree of freedom of movement even if they are not directly involved in the work. Many unnecessary joints are fixed with a brake, and the joints of the arm at the tip control the required degree of freedom when performing work. For easy understanding, a two-dimensional plane manipulator as shown in FIG. 11 will be described as an example. In this case, since the degree of freedom of the plane movement is 3, the 6-joint serial link type manipulator as shown has three redundant degrees of freedom.

If all the six joints of this serial link are activated and a tip force is applied, the load on the joints (92, 93, 94) on the side of the base portion 91 becomes large. 3 joints 9 from 91 side
2, the joint 93, and the joint 94 have three degrees of freedom fixed by a brake, and the joint 97, the joint 96, and the joint 95 from the side of the effector portion 98 at the tip end are operated with three degrees of freedom, thereby making it stronger. Try to generate tip power.

On the other hand, although the tip force may be a slight force, the work itself by the effector portion may require a corresponding torque force. In this case, operate with the operating finger of the effector part as a lever, or by attaching the effector part to the work target and letting the work load escape to the operation object, operate within the effector part or with the effector part. Work as if operating with internal force between objects.

FIG. 12 is a view for explaining an example of operation with internal force by a plurality of operating fingers of the end effector. An example of the stripping operation of the coating is shown in FIGS. 12 (A) to 12 (C). In this case, the operating finger of the effector is controlled so that the internal force can be operated so that force / torque due to the operation is not applied to the arm. In FIGS. 12A to 12C, 120 is a covered casing part, 121 is a covered 1
22 is an effector unit, 123 is an arm, and 124 is an operating finger. In the case of stripping the coating, first, as shown in FIG. 12A, the operating finger 12 of the effector section 122 of the arm
4 into the gap between the housing 120 and the cover 121, and
As shown in FIG. 2B, the operation finger 124 is opened. In the gap between the opened casing 120 and the cover 121, FIG.
As shown in (C), the operation finger 124 is further inserted to continue the stripping operation of the coating.

Further, in the work of pulling out the pin, as shown in FIG.
When pulling out 26, the auxiliary arm 1 of the effector section
The tip of 27 is attached to the mounting surface 125, and the jig 1
The pin 126 to be operated is grasped by 28, and the jig 1
By moving 28 upward, the pin 126 is pulled out. As a result, no force or torque is applied to the arm 123 due to the operation.

The operation of the effector section by such an internal force is extremely effective especially when performing service work in the unmanned spacecraft. This is a simple internal force operation interface (handle, recess, protrusion, etc.) for the object to be operated.
By making it easier to perform the operation. As a result, the required work force can be carried by the effector section, and the tip force of the manipulator arm and the work force of the effector section can be separated.

When the reconfigurable multi-limb space manipulator system according to the present invention is used to construct a system for a microscopic force manipulator for space, for example, the system configuration is as follows.

Small system by miniaturization of steady tip force ORU (Orbital Replacement Unit;
Equipment compatible with on-orbit exchange) exchange, on-orbit inspection, EV
When examining and analyzing space work such as A and IVA in detail,
With a tip force of about 5 to 10 N and a torque of about 5 Nm (hereinafter referred to as tip force), many operations can be performed without losing efficiency. It can be seen that a space manipulator with a small tip force (fine force manipulator) is effective as a robot that cannot exist on the ground. As a result, the joint output torque of a small space manipulator has been conventionally reduced to 10 to several liters.
The joint of the space manipulator which has been configured with 0 Nm is 5
A robot having a slimness and a light weight can be obtained by setting it to 10 Nm or less.

Effector work by internal force On the other hand, the tip force may be a slight force, but the work itself by the effector portion requires appropriate force and torque. For this reason,
Operate with the operating finger of the effector part as a lever, attach the effector to the work target, and let the work load escape to the operation object, and operate with the internal force inside the effector or between the effector and the operation object Work in this way.

This is extremely effective especially when performing service work in an unmanned spacecraft. For example, it can be easily realized by providing the operation object itself with a simple internal force operation interface. As a result, the required work force can be carried by the effector unit, and the manipulator tip force and the effector work force can be separated.

Equipped with instantaneous strong tip force In space work, strong instantaneous torque / instantaneous force of several seconds or less, such as final torque of tightening, torque of start of loosening, short-term or intermittent force operation to mechanism in abnormal state, etc. Is desired. To do this, as a joint motor,
A DC motor or step motor is used, and a large drive current is applied to the indirect motor instantaneously (1 to 5 seconds). As a result, driving can be performed while considering thermal constraints. In this case, there is a constraint on the load bearing capacity of the gear part, and in the harmonic drive that is often used in joints of small space manipulators, ratcheting torque is a constraint. Allowable torque.

Method of Operating with Stronger Steady Tip Force Even if the manipulator is made to have a small force, the manipulator system in the form of serial connection with a multi-degree-of-freedom system configuration, in particular, aims to maximize the tip force. As an effective operation method, in addition to an operation method that positively utilizes the normally considered singularity, a method that produces only a short span of movement by operating with only the degree of freedom of the tip.
As explained in Fig. 11, joints near the base part with the largest load are not used for operation, and brakes and controls (+ reducer
It is fixed by back-drive-torqe), and the operation is performed by operating only the degree of freedom on the tip side.

As described above, according to the reconfigurable space type multi-limb manipulator system of the present invention, the hollow boom portion of the manipulator arm is provided with the wire harness by the distributed control computer and the high-speed serial communication bus. The number of wires in the wire harness is reduced by the high-speed internal communication function.

In order to realize a space robot arm having a walking movement function / reconstruction function as a component when constructing a space micromanipulator system, in terms of weight and system configuration, It is necessary to reduce the wire harness (wiring inside the manipulator), but according to the conventional method, the number of wirings exceeds 100. Therefore, when the wire harness is passed through the manipulator arm, the loss torque at the joint portion reaches, for example, -10 Nm or more. That is, a large joint force is required just to bend the wire harness. Further, in order to compensate the position of the serial link of the flexible joint, it is necessary to equip some cameras, which also increases the number of wire harnesses. In order to realize walking movement and reconfiguring function, it is necessary to attach / detach the power line / signal line connector that is connected at the base, but if the number of harnesses is large, the manipulator tip and the moving / reconfiguring port will be large. Must be equipped with a port.

According to the reconfigurable multi-limb manipulator system for space of the present invention, such a problem can be solved by using, for example, an embedded microcomputer (32-bit processing RISC computer) as a distributed control computer. General-purpose interface for data communication (USB; IEEE1394)
The problem is solved by equipping a high-performance serial communication bus using.

The video signal photographed by the CCD camera section 67 of the effector section is digitized, and JPEG compression is performed by the middleware (intermediate signal processing section) in the distributed control computer provided in the boom section for high speed serial communication. By serial transfer via the bus,
The delay time due to the communication processing is several hundreds msec or less, and the video of any video channel can be transmitted to telemetry or an advanced image processing computer.

Further, joint control is performed by a distributed control computer incorporated in the boom portion of the manipulator arm, and control signals for cooperative control between joints and manipulator arms are transferred in the same manner as in the high-speed serial communication bus. Transfer through. With regard to the transmission of control signals of various special devices attached to the effector unit, the control signals can be transmitted and controlled by the high-speed serial communication bus by standardizing the bus interface. As a result, the number of wire harnesses in the arm can be minimized, and even if the transmission of video signals from various places is included, it is practically possible.
The number can be reduced to about 20 and the bending loss torque of the wire harness can be reduced, and the equipment related to the movement / reconstruction can be remarkably miniaturized, and the robot system can be matched.

Next, the structure of the effector portion which is used for both movement and operation will be specifically described. The effector unit equipped at the tip of the manipulator has a moving port function and the maximum operation function, and does not require a new connecting member by modularization. 13 to 16 are diagrams illustrating the configuration of the end effector and various operation examples by the operating finger. FIG. 13 is a partial sectional view of the end effector for explaining the truss operation. A plan view is shown in FIG. 13 (A), and a front view is shown in FIG. 13 (B). In the figure, 130 is an end effector, 131 is an arm,
Reference numeral 132 is an operating finger, 133 is a CCD camera, 134 is a light emitting diode for illumination, and 135 is a connector. As illustrated, in the truss operation, the three operating fingers 132 of the end effector 130 grip the grip portion of the truss structure. The grip portion of the truss structure is provided with a cutout portion in alignment with the positions of the three operating fingers 132, and the three operating fingers 132 are gripped so as to match this.

FIG. 14 is a partial view of the end effector for explaining the tether anchor operation. In the figure, 130 is an end effector, 132 and 132a are operating fingers, and 133.
Is a CCD camera, 134 is a light emitting diode for illumination, 1
35 is a connector, 141 is a first anchor, 142 is a second anchor, and 143 is a third anchor. As shown, in the anchor operation, the end effector 130
The operation finger 132a is used to operate the nail of the anchor. In the operation example of FIG. 14A, since the claw of the anchor is pulled back by the spring force, the claw of the anchor 141 is operated by moving the operating finger 132a upward. As shown in FIG. 14B, the second anchor 142
In this example, the operation finger does not have to be operated. Further, as shown in FIG. 14C, in the example of the third anchor 143, since the nail of the anchor is not operated by the force of the spring, it is operated by the operation finger 132a.

FIG. 15 is a partial sectional view of the end effector for explaining the micro-conical operation. FIG. 15 (A)
When the micro conical 150 having the shape as shown in FIG. 3 is grasped by the three operating fingers 132 of the end effector 130, the constricted portion is grasped by the three operating fingers 132 from the shape of the micro conical 150. Grab it. In the figure, 130 is an end effector, and 13
1 is an arm, 132 is an operating finger, and 150 is a micro-conical. In this case, FIG. 15B and FIG.
As shown in (C), the mounting positions of the three operating fingers 132 are aligned with the constricted positions of the micro-conical to be operated and gripped.

FIG. 16 is a partial sectional view of the end effector for explaining the handrail operation. In the operation in this case, the handrail 16 having a shape as shown in FIG.
0 is gripped by the three operating fingers 132 of the end effector 130. In this case, FIG. 16 (B) and FIG.
As shown in (C), from the shape of the handrail 160,
One operating finger is engaged with the concave portion on the upper surface of the handrail 160, and the other two operating fingers are engaged with the cutout portions on the opposite side, and these are grasped and grasped. As in the case described above, in the figure, 130 is an end effector, 132 is an operating finger, and 160 is a handrail. Also in this case, the attachment positions of the three operating fingers 132 are aligned with the recessed portions and the cutout portions of the handrail 160 to be operated, and the handrail 160 is gripped.

As described above, in the reconfigurable multi-limb manipulator system for space of the present invention, the CCD camera provided in the end effector is provided with the wide depth of field camera. The space manipulator system joints that are used in a wide operating temperature range and storage temperature range often use playful designs to ensure thermal reliability. With such a simple design, it is difficult to expect high absolute accuracy in tip position reproducibility, especially when configuring a multi-degree-of-freedom serially coupled manipulator system. Therefore, since the positional accuracy required for robot work is relative accuracy with the operation object,
As a method to easily secure the relative accuracy by visual measurement,
Adopt a wide depth of field camera.

Further, it is effective to attach a marker for relative position measurement to an object of automatic machine operation (R-ORU or moving port), but avoid a large one (5 to 40 cm) as in the present situation. CCD for the end effector
A small (~ 1 cm) marker system that can measure close to the camera is used. For mounting the gripped ORU, etc.,
By measuring the relative position of U and Worksite with a camera on another arm and performing position control, a large-sized (conventional, several cm to several tens cm) insertion guide that has been conventionally used can be downsized. . To this end, the optical system of the CCD camera section of the end effector has a wide depth of field, can measure relative positions up to just before a contact of several mm, and is in a situation when another arm is operating. The visibility of up to several meters shall be secured in order to monitor and guide.
Such a so-called dark optical system is not suitable for a ground robot, but is particularly applicable to a system based on relatively slow operation such as space work.

Further, in the past, in order to improve the workability and to impart softness to the hand, a passive flexible mechanism is provided, or compliance control (the softness of the hand is realized by software). In addition, we have carried out a method of cooperatively controlling each joint based on the force / torque sensor information. Such a passive and flexible mechanism is not desirable for remote operation because the robot environment model cannot be determined, and the method of providing a force / torque sensor at the hand complicates the mechanism of the end effector.

Therefore, paying attention to the fact that the manipulator posture does not change significantly in the operation for which compliance control is expected in the robot arm for space use, the posture of ensuring the sensor sensitivity is taken by the multi-degree-of-freedom robot, and the servo of each joint is set. It is controlled by the above distributed computer in a programmable manner. Then, a method of controlling specified softness and damping is used by using a torque sensor incorporated in each joint.

Further, in order to improve the certainty and efficiency of the automatic machine operation and to simplify the system relating to the runaway of the robot, an onboard monitoring system is introduced. To easily perform on-board automatic monitoring, real-time coordinate management of robots / manipulators according to marker measurement by a monitoring camera can be mentioned. If the control systems are switched independently, the dual-armed feature allows one arm to work while the other monitors. As a result, it is possible to ensure and improve the efficiency of automatic machine operation and to make the system related to robot runaway robust and simple.

According to the reconfigurable multi-limb manipulator system for space according to the present invention, it is possible to design a system relating to reliability. Space equipment is usually designed to eliminate single points of failure because it is expensive and difficult to repair. In the conventional manipulator system for space, in the manned system, it is possible to replace it by EVA work in case of joint failure, and in the unmanned system,
Currently, the system has several single points of failure. As described above, the “N out of M” redundancy of the multiple winding joint and the drive amplifier for redundancy leads to complication and is not preferable as a system configuration method. Generally, it is difficult to achieve both dexterity and redundancy. In the system configuration according to the present invention, basically, a system is configured by a plurality of manipulator arms configured by simple elements without redundancy. The configuration of the entire robot system can be variously handled as follows, depending on the requirements of the spacecraft system used.

For example, when a manipulator system is used in a small-scale space system such as a space shuttle, a small platform, an orbital working machine, etc., the system configuration is designed so that the two-limb type manipulator satisfies the system function requirement. If possible, one manipulator arm will be added, and system design will be performed as a robot arm having a three-limb type manipulator system. When there is no failure, the three-limb type manipulator system is used with improved operability, and when there is a failure, the efficiency is reduced and the two-limb type manipulator system is used. Further, if the system configuration can be designed so that the system function requirement satisfies the system function requirement with the three-limb type manipulator, the manipulator arm with one limb for on-orbit standby will be provided, and the system will be configured with a total of four limb type manipulators.

By adopting such a reconfigurable multi-limb manipulator system, in the case of a spacecraft system having a long life, the failed manipulator can be recovered and replenished by the replenishment / recovery system. For large systems such as stations and space solar power generation platforms, determine the number of manipulators required as a whole from the requirements of reliability and operability, and use it as a three-limb, two-limb, or more multilimb system depending on the work. You can

Further, in order to create a robot that is effective in practical use, it is important to design a system that has expandability and versatility and to update it sequentially. The reconfigurable space multi-limb manipulator system according to the present invention is not a conventional central / lower-level computer system configuration but a distributed system, which is backward-compatible and has a higher-performance communication function and end effector function. By adding a new high-performance manipulator with, it is possible to use the old manipulator while developing the system without making it obsolete. This is a great advantage not seen in the past.

As described above, the reconfigurable space multi-limb manipulator system can constitute a space robot system that achieves the intended purpose. Such a robot arm system is effective under microgravity or weightlessness such as on an orbit, and by the same concept, the moon of gravity (1/6) g or gravity (1/2) g
It can be easily extended to work robots on Mars' surface. Further, it is easy to change the sizing according to the size of the work target.

[0088]

As described above, according to the reconfigurable multi-limb manipulator system for space of the present invention, the system can be used for space experiments on an unmanned vehicle or an unmanned platform depending on the system configuration of the robot arm. -It can be used for system inspection and maintenance, robot assembly in small missions, space experiments, etc. In addition, when used in a manned system, it reduces crew work during simple space experiments onboard ships, supports simple inspection and maintenance and space experiments outside the ship, and automatically operates by robots during unmanned operations. Applicable.

[Brief description of drawings]

FIG. 1 Conventional Shuttle-R for Space Shuttle
It is a figure explaining the robot arm of MS.

FIG. 2 is a diagram illustrating a JEMRMS parent arm for a space station under development.

FIG. 3 is a diagram illustrating an SSRMS for a space station under development.

FIG. 4 is a diagram illustrating a system having a conventional single-arm / multi-arm manipulator.

FIG. 5 is a diagram showing a configuration example of a three-limb manipulator system of an embodiment of a reconfigurable multi-limb manipulator system for space according to the present invention.

FIG. 6 is a diagram showing a configuration example of a two-limb type manipulator system of the same embodiment.

FIG. 7 is a block diagram showing a circuit configuration of an electric system provided inside a boom of an arm of a manipulator.

FIG. 8 is a diagram illustrating a first mode of a work mode in a case where a manipulator system is configured by connecting three manipulator arms having six degrees of freedom.

FIG. 9 is a diagram illustrating a second form of a work mode in the case where a manipulator system is configured by connecting three manipulator arms having six degrees of freedom.

FIG. 10 is a diagram illustrating a third form of a work mode when a manipulator system is configured by three manipulator arms having six degrees of freedom.

[Fig. 11] Fig. 11 is a diagram for describing an operation example according to the degree of freedom of the tip of the multi-degree-of-freedom serial link manipulator.

FIG. 12 is a diagram for explaining an operation example with internal force by a plurality of operation fingers of the end effector.

FIG. 13 is a partial cross-sectional view of an end effector for explaining truss operation.

FIG. 14 is a partial view of an end effector illustrating a tether anchor operation.

FIG. 15 is a partial cross-sectional view of an end effector illustrating a micro-conical operation.

FIG. 16 is a partial cross-sectional view of an end effector for explaining a handrail operation.

[Explanation of symbols]

50 arm 51 joint part 52 end effector 53 boom 54 robot center part 55, 56 coupling port 57 spacecraft 61, 62 manipulator arm 61a, 62a, 62b end effector 61b coupling port 63 wire harness 64 joint drive circuit 65 distributed control computer 66 Communication processing circuit 67 CCD camera section 68 Connector section 71 End effector section 72 Joint section 73 Boom section 74 Joint motor 76 Camera body section 77 Preprocessing / A / D conversion section 78 Focus control lens drive control section 81, 82, 83 Arm 91 Bases 92, 93, 94, 95, 96, 97 Joints 98 Effector 100 Robot arm 120 Covered housing 121 Covering 122 Effector 123 Arm 124 Operating finger 125 Mounting surface 126 Pin 127 Auxiliary arm 128 Jig 130 End effector 131 Arms 132, 132a Operating finger 133 CCD camera 134 Light emitting diode 135 for illumination Connector 141 First anchor 142 Second anchor 143 Third anchor 150 Micro-conical 160 Handrail 201 Replenishment unit pressurization Ward 202 manipulator 203 precision work robot arm 204 replenishment part exposure section 205 airlock 206 exposure part 207 pressurizing section 301 space station 302 mobile transporter 303 mobile remote service base system 304 space station remote manipulator 305 robot Arm 401 robot arm 402 arm monitor camera 403 arm hand camera

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiaki Okami 2-12-1, Ookayama, Meguro-ku, Tokyo Within the Department of Mechanical and Space Engineering, Faculty of Engineering, Tokyo Institute of Technology (56) Reference JP-A-9-29671 (JP, A) ) Japanese Patent Laid-Open No. 4-300174 (JP, A), edited by Japan Standards Association, JIS Industrial Dictionary, Japan, Japan Standards Association, July 15, 1998, 4th edition, page 2067 ( Japan Robot Industry Association Public Relations Committee, Robot Handbook, Japan, Japan Robot Industry Association, March 31, 1995, 1995 edition, pp. 7-9, 56 (58) Fields investigated (Int.Cl . ^7, DB name) B25J 9/00 - 11/00 B64G 1/24

Claims (6)

(57) [Claims] 1. A reconfigurable multi-limb space manipulator system for performing various space operations under low gravity, comprising a plurality of manipulator arms having the same system components. One manipulator arm functions as one robot, and the system configuration is configured such that a plurality of manipulator arms are connected to each other to change the form and function as one or a plurality of robots. Reconfigurable space multi-limb manipulator system. 2. The reconfigurable multi-limb manipulator system for space according to claim 1, wherein the manipulator arm has an arm connecting a plurality of joints by a hollow boom, and an operation provided at both ends of the arm. An end effector having a finger and an electrical coupling portion, and a distributed computer that performs high-speed serial communication processing and robot control provided inside the hollow boom, the distributed computer, cooperative control of the entire robot system,
Robot control that performs monitoring processing to monitor other manipulators, communication control processing for high-speed communication lines, and functions that are changed according to the robot configuration configured as a manipulator consisting of multiple manipulator arms A reconfigurable multi-limb manipulator system for space, which performs central calculation and performs perceptual data processing and data relay depending on the form. 3. The reconfigurable multi-limb manipulator system for space according to claim 1, wherein the manipulator arm has an operating finger of basically one degree of freedom and an electrical coupling connector at both ends of each arm. Equipped with an end effector, the end effector has a function of operating an operation target, and it is electrically and mechanically connected to other manipulator arms by gripping a dedicated port prepared on a spacecraft or robot system. Reconfigurable multi-limb manipulator system for space. 4. The reconfigurable multi-limb manipulator system for space according to claim 1, wherein the arm of the manipulator arm has a small motor and a drive circuit with an output margin, and an instantaneous force is used as a joint function. Is a small joint that is larger than steady force, and is configured to exert a larger operating force than continuous output in a short time, a reconfigurable multi-limb manipulator system for space use. 5. The reconfigurable multi-limb manipulator system for space according to claim 1, wherein the manipulator arm includes an arm having a plurality of joints connected by a hollow boom, and operating fingers provided at both ends of the arm. And an end effector having an electrical coupling part, and a distributed computer for performing high-speed serial communication processing and robot control provided inside the hollow boom, the end effector having a dedicated interface for the robot. The reconfigurable multi-limb for space operation characterized in that the operation target is operated by the internal force operation of the operating finger of the end effector, and the operating finger of the end effector is a mechanism in which force torque generated at the time of operation is not transmitted to the arm. Manipulator system. 6. The reconfigurable multi-limb manipulator system for space according to claim 1, wherein the manipulator arm includes an arm having a plurality of joints connected by a hollow boom, and operating fingers provided at both ends of the arm. And an end effector having an electrical coupling part, and a distributed computer for performing high-speed serial communication processing and robot control provided inside the hollow boom, and the end effector is provided with a dedicated port or a dedicated operation object. A reconfigurable multi-limb manipulator system for space, which is equipped with a small camera with a wide depth of field for measuring a small marker for measurement.