Showing papers on "Articulated robot published in 1997"

A Rubbertuator-based structure-climbing inspection robot

Abstract: We describe our progress on the development of ROBIN, a robotic inspector. ROBIN is a structure-climbing robot designed for man-made environments. It is intended to carry cameras and other sensors onto man-made structures such as bridges, buildings, aircraft and ships for inspection. The robot has two vacuum fixtures connected by a 4 degree-of-freedom articulated mechanism that together allow it to walk across surfaces and will permit transition between adjacent surfaces. ROBIN is novel in several areas. It is the only climbing robot that uses McKibben type pneumatic muscles for movement. It is also novel in its use of a subsumption architecture controller in a climbing robot. ROBIN is one of the few climbing robots that is equipped with a mechanism that is capable of transitions between surfaces or from a horizontal surface to a vertical surface below.

Robot system and robot control device

Abstract: An object of the device according to the present invention is to enable small-volume, high-diversity production to be conducted efficiently, in the same way as in the conventional FMS, whilst at the same time overcoming problems associated with the conventional techniques, such as the complexity of creating programs for manufacturing processes, work interruptions due to robot breakdown, and `deadlock` incidents arising during operation. When seed data indicating an objective task (for example, the task of completing a particular product) is input to a computer, by communicating with hardware robots via a communications network, the computer selects a plurality of hardware robots, which are capable of implementing cooperatively the objective task indicated by the input seed data, and which are not engaged in any task based on other seed data. A software robot is created by inputting the seed data to at least one of the selected plurality of hardware robots. When the plurality of robots have been operated by means of the generated software robot and have completed the objective task, the seed data is withdrawn from the hardware robot(s) to which it was input.

Teachingless spray-painting of sculptured surface by an industrial robot

Abstract: The study deals with the automatic spray-painting by a 6-DOF industrial robot equipped with an air spray gun. Since the conventional robot control command generation for the spray-painting is manually performed by skilled workers using a teaching-playback function of a robot controller, it is a time consuming and experience required process. The study aims at generating the robot control commands without any special knowledge on spray-painting, in the case of bumpers of a car as an example of sculptured surfaces. The system can automatically generate a spraying path for the air spray gun on the basis of CAD date of the workpiece, and change the spraying path into robot control commands. From experimental results, the system was found to be effective in painting bumpers of a car with uniform paint thickness.

Robot assembly system for the construction process automation

Abstract: This paper presents a robot assembly system for the construction industry based on an articulated robot placed over a mobile platform. The assembly process and the robot has been developed under the computer integrated construction concept. Its main task is the assembly of blocks for the erection of walls in industrial buildings.

A simple driving device for a vehicle implementation and evaluation

Abstract: We are interested in the operation facilities of vehicle that are simple even for persons who are not experienced in vehicle operation. One idea simplifying the vehicle operation is to separate the operation from the mechanism of the vehicle. In this system, the human operator specifies a temporary goal position of the mobile robot by touching the monitor in which front view images are displayed. The robot then travels toward this goal position. The path to the goal position is generated by the system and shown on the front view images. Therefore, the operator need not practice how to operate steering wheel or accelerator. We have constructed an experimental setup and evaluated it by controlling the robot.

Offset rotation joint, and articulated robot having same offset rotary joint

Abstract: PROBLEM TO BE SOLVED: To provide an articulated robot, and a joint mechanism for that in which motion of a large freedom degree can be obtained by combination of joints each having a rotation mechanism only, in which weight reduction and high power of the joints can be achieved, in which payload to self-weight is large, and in which multi-stage articulation, a large moving range, and complicated and precise motion can be achieved. SOLUTION: A rotation control frame provided with a coreless electric direct drive motor on an inclined surface to a link axial line is provided between a driving side link and a driven side link to compose an offset rotary joint 5 having an offset rotation axial line OA in which the driven side link is inclined to a link axial line LA, and the offset rotary joints are provided in plural stages between a robot main body 3 and an end effector 4, thereby precise three-dimensional positioning of the end effector 4 can be performed by composite motion of the offset rotary joints 5. COPYRIGHT: (C)1998,JPO

Calculation of the direct dynamic model of walking robots: comparison between two methods

Abstract: In this paper, two methods to calculate the direct dynamic model (DDM) of walking robots are presented. These methods derive from the Walker-Orin (1982) method and from the Featherstone (1983) method, generally used to compute the DDM of robot manipulators. The comparison is made on the number of operations for each method and for walking robots: a biped robot and a quadruped robot. It is shown that Featherstone's method is better than Walker-Orin's one.

Golf-swing robot emulating a human motion

Abstract: The performance of golf clubs and balls is generally evaluated using a golf-swing robot that conventionally have two or three joints with completely interrelated motion. This interrelation allows the user of this robot to specify only the initial posture and swing velocity of the robot and thus, the swing motion of this type of robot cannot be subtly adjusted to the specific characteristics of individual golf clubs. Consequently, golf-swing robots cannot accurately emulate professional golfers and this causes serious problems for the evaluation of the performance of golf clubs. In the paper, a golf-swing robot that can adjust its motion to both, a specified value of swing velocity and the specific characteristics of individual golf clubs is investigated analytically.

Wrist mechanism for articulated robot

Abstract: PROBLEM TO BE SOLVED: To provide wrist mechanism for an articulated robot high in rigidity and simple in structure without the offset of a wrist part. SOLUTION: An inclined arm 101 inclined in relation to the longitudinal direction of an arm 1 is provided at the tip of the arm 1. A fitting seat 103 parallel with a rotation axis R is provided at the side face on the side facing the rotation axis R, and a housing 102 is fixedly provided at the tip of the inclined arm 101. A driving part for driving a wrist part 2 is composed of a driving motor 5 fixed to the inside of the inclined arm 101, along the inclined direction, and a speed reducer 4 fitted to the fitting seat 103 of the housing 102. An output shaft 51 of the driving motor 5 and an input shaft 42 of the speed reducer 4 are coupled by the mesh of two bevel gears 52, 43.

The development of a micro robot system for robot soccer game

Abstract: In this paper, we present the design and the structure of our multiple micro-robot system, CENDORI, designed for playing a robot soccer game, MIROSOT. A robot soccer game is a very complex robot application that incorporates real-time vision, robot control wireless communication and management of multiple robots. To build a robot system with high performance and reliability, we designed the system architecture with a centralized concept. The robot control relies largely upon the vision system and the host computer generating low level motion control words. The experimental results and the performance of the robot are discussed.

Fuzzy controller for wall-following with a nonholonomous mobile robot

Abstract: This paper describes the design and development of a sensor based navigation system which makes it possible for a nonholonomous mobile robot to follow walls using information on its environment picked up by a belt of ultrasonic sensors. To control the robot no preliminary information regarding its environment is required, the robot adapts to them through the information gathered on the spot by the ultrasonic sensors and the information released from a spatial memory. The controller allows the generation of the signal to the robot motors. It has been developed in two directions: one being based on the concept of general perception, and the other on the concept of distributed perception. In carrying out both of these lines of development, the principle of fuzzy logic has been applied. The navigation system has been tested on a prototype mobile robot (VEA-II) developed at IKERLAN, which is highly manoeuvrable and capable of moving both in a holonomous and nonholonomous configurations.

Designing simple cooperative sensor/actuator robots for liquid process environments

Abstract: Summary form only given. The detailed design of an autonomous sensor/actuator robot to be used in liquid environment is presented. The robot, SUBMAR (smart underwater ball for measurement and actuating routines), is a small ball-shaped device with 11 cm diameter. It is capable of performing semi-active motion in the process liquid, estimating its own position roughly, taking measurements with the onboard sensors, collecting samples, actuating the process chemically, and communicating across small distances. Semi-active motion means that the robot moves mainly along the process flow, but it can also move vertically by changing its specific weight with the aid of a diving tank. This solution saves considerable amounts of energy, the most critical resource of all autonomous devices. SUBMAR is capable of operating alone as an autonomous robot, but it is intended and designed to work as a member of a multi-agent robot society.

Development of In-pipe Inspection Robot for Small Radius Pipelines

Abstract: We have already reported the fundamental mechanism for an in-pipe inspection robot which can move in small radius (50 [mm] ) pipeline. The robot could go through elbows and T-joint, but only in horizontal pipelines. In this report, we describe a new in-pipe inspection robot that is extended to go through both horizontal and vertical pipelines with computer control. The robot has 2 steering units at both end, and each steering unit has 2 D.O.F to change the direction of the robot. In order to be controlled automatically, the robot should know the shape of pipeline, the status of the robot and locomotion distance, the robot has various sensors such as tactile sensors, an encoder and potentiometer. Using the information from these sensors, the robot can move along not only straight pipeline but also elbows or T-joint automatically.

Development of an automated fixture set-up system for inspection

Abstract: This paper presents an automated fixture set-up for inspection. The system comprises a workplace with magazines, locators and a baseplate. An articulated robot, the SCORBOT-ER VII is used to automate the system. A C-program is developed and used to execute robot arm movements based on user input. The C-program also establishes locating postions for a rectangular workpiece and determines the set-up of the locating fixtures via points. The program is therefore a useful interface to other small-scale expert systems for fixture design and graphical simulators. The set-up of the fixtures can be performed for other complex shapes if locating points are known, and input into the robot controller using the C-program.

Impedance control for articulated robot of 6 degree-of-freedom in consideration of critically damped condition with an object dynamics

Abstract: This paper presents a new position-based impedance control that can take into account of a desired position in the force control, and gives a transformation technique from the position command to the torque command in order to apply the control to an industrial robot whose servo system is opened or to implement it in computer simulations. In order to determine a suitable compliance without trial and error, this paper introduces a new method that produces the desired time-varying compliance, giving the critical damping in contact with an object, by using information on inertia matrices. Simulation results have shown that the proposed methods are very effective for realizing it in industrial robots and for deciding the desired compliance without any complicated tuning.

Wrist structure for vertically articulated robot

Abstract: PROBLEM TO BE SOLVED: To wire and pipe a cable, etc., from the wrist at the end of a robot arm to an end effector without exposing them to outside, as far as possible. SOLUTION: In the structure of mounting an end effector to the wrist of a vertically articulated robot, a wrist flange is provided on the wrist 26 rotatably mounted at the end of a robot arm 16 to be rotatable around an axial line a 4 and the end effector 28 is mounted on the wrist flange via a sectionally U-shaped mounting member for which two members, separating and opposing each other in parallel to the mounting face of the wrist flange, are connected together via a member in parallel to the axial line a 4 , in such a manner that at least part of a cable between the wrist 26 and the end effector 28 can be covered with the sectionally U-shaped mounting member. COPYRIGHT: (C)1998,JPO

Design and implementation of brain real-time part for remote-brained robot approach

Abstract: In this paper, we describe the design implementation of this real-time layer for remote-brained robot. "Remote-brained approach" is a paradigm for software research by separating the robot brain from the robot body. The interface from the body to the brain top-level software is also denoted. Furthermore, an application of the reactive motion of humanoid-type robot is described. The real-time facility is fundamentally important for a robot that behaves in the read-world. To accomplish both large scale intelligent software and real-time functionality, we design the system by dividing the brain into a low-level real-time layer and a high-level action decision layer. The action decision layer is put on a WS, and the real-time layer is put on a transputer network.

Articulated robot and position teaching method of articulated robot

Abstract: PROBLEM TO BE SOLVED: To allow to teach the positions of operating parts easily by maintaining the relative position relation of plural operating parts, in the joint parts to combine plural operating parts SOLUTION: In an articulated robot 1 fin which plural operating parts are provided, and the position of a moved random operating part is taught by moving the random operating part directly by an operator, a brake mechanism 30 to maintain the relative positional relation of plural operating parts which are combined through the joint parts 10, 11, 12, and 13 is furnished at the joint parts 10, 11, 12, and 13 to combine the plural operating parts, and this brake mechanism 30 can release the maintaining of the relative positional relation of plural operating parts, at the joint parts 10, 11, 12, and 13 relating to a random operating part the operator is going to operate by moving directly

Cable processing method for tool of articulated robot and cable processing device

Abstract: PROBLEM TO BE SOLVED: To prevent a cable from being intertwined to the tip end tool of an articulated robot. SOLUTION: The rotating angle of a fourth through a sixth joint D through F located between the base end part of a cable 11 and a spray gun 5 is detected, and when the relative rotating angle of the application gun 5 with respect to a third arm part 4C is equal to or more than a prescribed value, a fifth joint E is driven so as to allow the third arm part 4C through a sixth arm part 4F (the gun 5) to be stretched in a straight line, and the fourth and sixth joints D and F are returned to their original positions thereafter, so that the cable 11 is thereby prevented from being intertwined.

Robot Motion Planning

Abstract: One of the ultimate goals in robotics is to design autonomous robots: robots that you can tell what to do without having to say how to do it. Among other things, this means a robot has to be able to plan its own motion.

Decoupling Control of Base Attitude and Hand Trajectory for Free-Flying Space Robot.

Abstract: In this paper, the free-flying space robot, comprising a satellite base body and articulated manipulator arms, is considered. We clarify the reduced effective inertia of this sophisticated mechanism is smaller or equal to the effective inertia associated with the articulated manipulator arm which is fixed on the earth. Furthermore, we develop the control system which decouples motions of satellite base body with the end-effector movements with application to control system for capturing a turget by a space robot. Finally numerical simulations demonstrate the usefulness of the proposed control system.

Virtual Reality Based Robot Graphic Simulation and Virtual Manufacturing System

Abstract: This paper reports research into an interface between industry robots and Virtual Reality systems and creates a virtual robot for robot arm simulation, control language conversion, physical communication, robot networking and teleoperation control. The paper is based on an integrated manufacturing networking software which includes a PUMA robot, a Lansing welding robot, and CNC machines. The aim of the research is to combine VR and robot technology for system testing, to establish VR based simulation workshop for defining and checking robot arm movement trajectory, eliminating the chance of potential collision. The paper also presents a system that can interpret the recognised operations into operator-level commands using task-dependent interpretation rules and a world model. A robot executes the defined task in the workspace by replicating operator’s movements in the virtual workspace.

Robust Decoupling Control for Articulated Robot

Abstract: In an articulated robot, coupling forces are generated between the joints. To improve dynamic behavior and reduce the work cycle time, it is necessary to compensate for the force generated between the joints. In this paper, robot dynamics are expressed in a linear form by applying a gain scheduling method and then transformed into a discrete form. A simple control algorithm is proposed which can perform the decoupling and the pole assignment simultaneously by using an observer with a disturbance compensation function. The results, based on experiments with a SCARA-type robot, show that the proposed approach can compensate for the coupling force between joints.

Vertical articulated robot

Abstract: PROBLEM TO BE SOLVED: To easily form an arm direct-acting type robot as a fixed link type robot. SOLUTION: Links 10, 11, 12 and so forth are added to an arm direct-acting type robot without changing a robot mounting base 1, thereby forming a fixed link type robot. Also, an extension arm 15 is added to the second arm 15 having a robot wrist at a forward end, thereby increasing arm length for preventing the reduction of a working operation range. Also, the base 3 of the second wrist is turned around an axis offset from a slewing center, thereby minimizing an increase in interference radius. Furthermore, the change of the arm direct- acting type robot to the fixed ring type robot enables a robot wrist part to cope with a portable weight increase.

Using the algebraic structure of articulated robot dynamics in control design

Abstract: We discuss the algebraic structure of the dynamics of articulated multibody systems and how it may be effectively used in control design The dynamics has a decomposition consisting of matrix operators satisfying many identities and giving insight into the dynamical system To show the utility of this formalism, we investigate a disturbance attenuation control problem We introduce a meaningful performance index which has an interesting interpretation in terms of the 'normalized' robot dynamics Finally, we derive a new adaptive controller using the local structure found in the dynamics and test it on a 3-link planar robot arm

Device for welding internal face of box shape block

Abstract: PROBLEM TO BE SOLVED: To automatically and effectively weld an internal face of a box shaped block by installing a turning stand at the top end of a horizontal telescopic arm and mounting an articulated welding robot on the above SOLUTION: In the state with an opening part of a box shaped block 20 arranged in front of a fixing stand 2, a robot turning stand 4 is fallen forward and an articulated robot 10 is extended horizontally, a horizontal telescopic arm 3 is expanded, the articulated robot 10 is inserted inside the block from a narrow part of a diaphragm, etc, and it is stopped at a prescribed position Then, the robot turning stand 4 is turned, the articulated robot 10 is actuated, a welding torch is moved to the welding start point and the automatic welding is executed In this case, welding is executed by making the welding weaving frequency without the range of a resonance frequency ±05Hz of the device