Showing papers on "Articulated robot published in 2006"

Collision Detection and Safe Reaction with the DLR-III Lightweight Manipulator Arm

Abstract: A robot manipulator sharing its workspace with humans should be able to quickly detect collisions and safely react for limiting injuries due to physical contacts. In the absence of external sensing, relative motions between robot and human are not predictable and unexpected collisions may occur at any location along the robot arm. Based on physical quantities such as total energy and generalized momentum of the robot manipulator, we present an efficient collision detection method that uses only proprioceptive robot sensors and provides also directional information for a safe robot reaction after collision. The approach is first developed for rigid robot arms and then extended to the case of robots with elastic joints, proposing different reaction strategies. Experimental results on collisions with the DLR-III lightweight manipulator are reported.

Method for controlling a robot arm, and robot for implementing the method

Abstract: In a method for controlling a robot arm, which is particularly suitable for use in medical applications, a robot arm ( 10 ) with a redundant number of joints is used. A torque acting in at least one joint ( 12 a, 12 b ) is sensed. By means of a control device, the torque acting in this joint ( 12 a, 12 b ) is controlled to become substantially 0.

Free-Climbing with a Multi-Use Robot

Abstract: This paper presents a new four-limbed robot, LEMUR IIb (Legged Excursion Mechanical Utility Rover), that can free-climb vertical rock surfaces. This robot was designed to have a number of capabilities in addition to climbing (e.g., assembly, inspection, maintenance, transport, intervention) and to be able to traverse a variety of other types of terrain (e.g., roads, talus, dirt, urban rubble). To maximize its flexibility in this regard, LEMUR IIb will need to exploit sophisticated control, planning, and sensing techniques in order to climb, rather than rely on specific hardware modifications. In particular, this paper describes a new algorithm for planning safe one-step climbing moves, which has already enabled LEMUR IIb to climb an indoor, near-vertical surface with small, arbitrarily distributed, natural features. To the authors’ knowledge, this is the first experimental demonstration of a multi-use, multi-limbed robot climbing such terrain using only friction at contact points (i.e., free-climbing).

Reconfigurable balancing robot and method for dynamically transitioning between statically stable mode and dynamically balanced mode

Abstract: An apparatus and a method for robotic control that allows an unbalanced pendulum robot to raise its Center of Mass and balance on two motorized wheels. The robot includes a pair of arms that are connected to the upper body of the robot through motorized joints. The method consists of a series of movements employing the arms of the robot to raise the robot to the upright position. The method comprises a control loop in which the motorized drives are included for dynamic balance of the robot and the control of the arm apparatus. The robot is first configured as a low Center of Mass four-wheeled vehicle, then its Center of Mass is raised using a combination of its wheels and the joint located at the attachment point of the arm apparatus and the robot body, between the rear and front wheels; the method then applies accelerations to the rear wheels to dynamically pivot and further raise the Center of Mass up and over the main drive wheels bringing the robot into a balancing pendulum configuration.

Device and method for controlling robot arm, robot and program

Abstract: In a robot arm controlling device, a mechanical impedance set value of the arm is set by an object property-concordant impedance setting device based on information of an object property database in which information associated with properties of an object being gripped by the arm is recorded, and a mechanical impedance value of the arm is controlled to the set mechanical impedance set value by an impedance controlling device.

Leg Design for a Humanoid Walking Robot

Abstract: The paper presents the leg design of the 22-DoF humanoid walking robot Lola The goal of the project is to realize a fast, human-like walking motion The robot is characterized by its lightweight construction, a modular, multi-sensory joint design with brushless motors and an electronics architecture using decentralized joint controllers and sensor data processing Linear actuators are used for the knee and ankle joints to achieve a better mass distribution in the legs and to improve performance of the stabilizing control Some critical structural parts have been designed by means of topology optimization in order to balance the demands for high stiffness and strength with low weight

Dynamic Trajectory Planning of a Spherical Mobile Robot

Abstract: A spherical mobile robot, BHQ-1, designed for environment exploration, was briefly introduced. The dynamic model of BHQ-1 was established with a simplified Boltzmann-Hamel equation. From the dynamic model the expressions of the input moments of two motors to drive the robot are deduced when the robot moves along straight trajectory and circular trajectory separately. Simulation result of the robot to track a complex trajectory and experiments of the robot to avoid an obstacle show the trajectory planning method is effective.

Position-recognizing system for self-moving robot

Abstract: Disclosed is a position-recognizing system of a self-moving robot. A position-recognizing system of a self-moving robot includes: a floor in which a magnet is inserted; and a self-moving robot provided with a magnetic sensor that can sense the magnet while the robot is moving on the floor. According to this, a magnet mounted in a floor is sensed through the magnetic sensor, and thusly a current location of the self-moving robot can be accurately recognized, so that the self-moving robot can be precisely controlled.

Autonomous control of a snake-like robot utilizing passive mechanism

Abstract: Recently, autonomous robots which operate in unpredictable complex environment, for example in the rescue operation, in space development and so on have attracted much attention. Snake-like robot is one of typical example of them. However, to control the robot in the unpredictable environment is very difficult problem, because to model the environment is impossible and much information should be measured to move the robot at the complex unknown environment. In addition, many computational costs are required to calculate control law for many degrees of freedom. In this paper, for the first step, we consider autonomous control of the snake-like robot which moves to a light source on a horizontal plane that has many unknown obstacles. To solve the problems, we show importance of passive mechanism, and realize an autonomous control for a snake-like robot by utilizing the passive mechanism. To demonstrate the effectiveness of the proposed mechanism, we have developed a snake-like robot and experiments have been carried out. As a result effective behaviors have been realized

Design and Manufacturing of a Mobile Rescue Robot

Abstract: This paper presents design and manufacturing procedure of a tele-operative rescue robot. First, the general task to be performed by such a robot is defined, and variant kinematic mechanisms to form the basic structure of the robot will be discussed. Choosing an appropriate mechanism, geometric dimensions, and mass properties will be detailed to develop a dynamics model for the system. Next, the strength of each component is analyzed to finalize its shape. To complete the design procedure, Patran/Nastran was used to apply the finite element method for strength analysis of complicated parts. Also, ADAMS was used to model the mechanisms, where 3D sketch of each component of the robot was generated by means of Solidworks, and several sets of equations governing the dimensions of system were solved using Matlab. Finally, the components are fabricated and assembled together with controlling hardware. Two main processors are used within the control system of the robot. The operator's PC as the master processor and the laptop installed on the robot as the slave processor. The performance of the system was demonstrated in Rescue robot league of RoboCup 2005 in Osaka (Japan) and achieved the 2nd best design award.

Implementing a Human-Aware Robot System

Abstract: The presence of humans in the robot environment brings new challenges to the robotic research. From low level functions to high level planners, clearly the human has to be taken into account in all the layers of the robot control system. Indeed, the robot has to behave socially in order to interact friendly with its human partners. This paper describes the development of several components (human detection and tracking, planning and supervision) that take into account humans explicitly with some preliminary results of their integration.

Heli4: A Parallel Robot for Scara Motions with a Very Compact Traveling Plate and a Symmetrical Design

Abstract: This paper introduces Heli4 a new 4 degree-of-freedom parallel robot. It is inspired by the Delta architecture, but was designed to overcome its limitations, using an articulated traveling plate. Unlike most articulated traveling plates, Heli4's traveling plate is very compact. Among other positive aspects is its symmetrical design. This paper gives the geometrical models, and particularly the forward position relationship which can be obtained in a closed form. In a third part, a detailed study of the robot singularities is made by taking into account the not-so-classic internal singularities.

Design of a Biomimetic Spine for the Humanoid Robot Robota

Abstract: This paper presents a prototype of 3 degrees-of-freedom articulated spine for the doll-shaped humanoid robot Robota. This work follows an approach that emphasizes the need for a high human-likeliness in both the external features of the robot and in the kinematics of its motions to enhance human-robot interactions. The design of a spinal cord for our humanoid robot satisfies both criteria in providing offering a smooth human-like parallel means of bending forward and sideways

Cooking for humanoid robot, a task that needs symbolic and geometric reasonings

Abstract: This paper presents a work toward the old dream of the housekeeping robot. One humanoid robot will cooperate with the user to cook simple dishes. The system combines predefined tasks and dialogues to find a plan in which both robot and user help each other in the kitchen. The kitchen problem allows the demonstration of a large variety of actions, and then the necessity to find and to plan those actions. With this problem the task planner can be fully used to enhance the robot reasoning capacity. Furthermore the robot must also use motion planning to have general procedures to cope with the action planned. We focus on the planning problems and the interactions of these two planning methods

Superpositioning of behaviors learned through teleoperation

Abstract: This paper reports that the superposition of a small set of behaviors, learned via teleoperation, can lead to robust completion of an articulated reach-and-grasp task. The results support the hypothesis that a robot can learn to interact purposefully with its environment through a developmental acquisition of sensory-motor coordination. Teleoperation can bootstrap the process by enabling the robot to observe its own sensory responses to actions that lead to specific outcomes within an environment. It is shown that a reach-and-grasp task, learned by an articulated robot through a small number of teleoperated trials, can be performed autonomously with success in the face of significant variations in the environment and perturbations of the goal. In particular, teleoperation of the robot to reach and grasp an object at nine different locations in its workspace enabled robust autonomous performance of the task anywhere within the workspace. Superpositioning was performed using the Verbs and Adverbs algorithm that was developed originally for the graphical animation of articulated characters. The work was performed on Robonaut, the NASA space-capable humanoid at Johnson Space Center, Houston, TX.

Development and Control of a High Maneuverability Wheeled Robot with Variable-Structure Functionality

Abstract: Common wheeled robots face many difficulties when traveling in complex environments, especially its incapability to climb over obstacles higher than its wheel radius. Many alterations were made to these robots to allow them to travel in rough terrains or conquer high obstacles, nevertheless, most designs are complex in nature and lost several original wheeled robot advantages by gaining others. In this paper, we propose a novel wheeled type robot with variable structure functionality. It is designed with simple structure consisting of three main robot parts, the main body, the left and right wheel-arm units. The robot could achieve five locomotion modes that allows the robot to travel in various environments and climb over high obstacles. Moreover, the fast-speed advantage in flat floor condition that common wheeled robot originally hold is still remained. The confirmation of the effectiveness of the robot's maneuverability is shown by several experimental results.

Museum Guide Robot with Communicative Head Motion

Abstract: Face or head movement plays an important role in human communication. This paper presents a museum guide robot that moves its head to communicate smoothly with humans. We have analyzed the behavior of human guides when they explain exhibits to visitors. Then, we have developed a robot system that can recognize the human's face movement using vision. The robot turns its head depending on the human's face direction and the contents of utterances. We use the analysis results of human behavior to control the head movements. Experimental results show that it is effective for the guide robot to turn its head while explaining exhibits.

Mobile Robot with Preliminary-Announcement Function of Forthcoming Motion using Light-ray

Abstract: This paper discusses the design and the basic characteristic of the mobile robot PMR-1 with the preliminary-announcement and display function of the forthcoming operation (the direction of motion and the speed of motion) to the people around the robot by drawing a scheduled course on a running surface using light-ray. The laser pointer is used as a light source and the light from the laser pointer is reflected in a mirror. The light-ray is projected on a running surface and a scheduled course is drawn by rotating the reflector around the pan and the tilt axes. The preliminary-announcement and display unit of the developed mobile robot can indicate the operation until 3-second-later preliminarily, so the robot moves drawing the scheduled course from the present to 3-second-later. The experiment on coordination between the preliminary-announcement and the movement has been carried out, and we confirmed the correspondence of the announced course with the robot trajectory both in the case that the movement path is given beforehand and in the case that the robot is operated with manual input from a joystick in real-time. So we have validated the coordination algorithm between the preliminary-announcement and the real movement.

A mobile robot that performs human acceptable motions

Abstract: The presence of humans should be explicitly taken into account in all steps of robot's design and particularly for robot motion. The robot should reason about human partner's accessibility, his vision field and potential shared motions and behave as a social being by respecting social rules and protocols. This paper describes the algorithms and results of a navigation planner that takes into account the human presence explicitly. This planner is part of a human-aware motion and manipulation planning and control system that we aim to develop in order to achieve motion and manipulation tasks in presence and/or in synergy with human.

Robot programming device

Abstract: A robot programming device, in which the teaching of the cooperative motion of a plurality of robots may be carried out in a short time so as to reduce the number of man-hours for starting-up a robot system including the robots. The robot system includes two handling robots each having a hand for gripping a workpiece and a welding robot having a welding torch, a robot controller for controlling the robots, a personal computer with a robot programming device connected to the controller, and a teaching operation panel connected to the controller for teaching each robot.

Designing simple and effective expression of robot's primitive minds to a human

Abstract: This paper describes designing expression of robot's primitive minds in a simple and effective way. Although expression of robot's minds like internal states is becoming a major topic in human-robot interaction, few studies to propose a policy to design concrete expression. In this paper, we propose the design policy, called "SE2PM: simple expression to primitive mind", and fully implement expression of robot's minds based on the design policy, then investigate the effectiveness of them. SE2PM implies that intuitive and simple expression like a beep sound from a simple robot (e.g. a mobile robot) is more effective than complicated behaviors from a complex robot (e.g. a dog-like pet robot) in informing its primitive minds to a human. Thus, in order to investigate the validation of our SE2PM policy, we implement two robots: a mobile robot based on Mindstorms with mind expression of beep sound, and a pet robot, AIBO, with mind expression of complicated behaviors. We also conduct a psychological experiment with participants to compare the two different expression, and the results eventually support SE2PM policy

Design of a Reconfigurable Space Robot with Lockable Telescopic Joints

Abstract: This work presents a new paradigm and a conceptual design for reconfigurable robots. Unlike conventional reconfigurable robots, our design does not achieve reconfigurability by utilizing modular joints. Rather, the robot is equipped with passive joints, i.e., joints with no actuator or sensor, which permit changing the Denavit-Hartenberg parameters such as the link length and twist angle. The passive joints will become controllable when the robot forms a closed kinematic chain. Also, each passive joint is equipped with a built-in brake mechanism which is normally locked, but the lock can be released whenever the parameters are to be changed. Not only will such a manipulator have the versatility to perform different tasks but also it can be packed adequately within its designated space on the launch vehicle. Kinematics of such a robot is analyzed, and a stable control algorithm which can take the robot from one configuration to another is devised.

Ultrasonic trimming device

Abstract: An ultrasonic trimming device comprises an articulated robot, a cutter, and a grindstone. The cutter comprises an ultrasonic oscillator supported at the distal end of the articulated robot, a cutter blade supported by the ultrasonic oscillator, and a work securing portion for securing a work. The grindstone, i.e. an abrasive member arranged in the movable range of the cutter blade driven through the robot, is located at such a position as it can come into pressure contact with the cutter blade. The cutter blade is subjected to ultrasonic vibration by the ultrasonic oscillator under such a state as it is pressed against the grindstone by the articulated robot and polished. With such an arrangement, even a three-dimensional curved surface of a sheet material or a composite material composed of a soft material such as plastic, cloth or rubber or a material including glass fiber is cut efficiently by a method where the environment is taken into account.

A Mechatronic Platform, The Aldebaran Robotics Humanoid Robot

Abstract: For several years, humanoid robotic has an important place in the research area. But nowadays, humanoid robots are everywhere : movies, advertising, toy... The world seems to be ready for biped robot. In this paper, a new mechatronic platform is introduced : The Aldebaran Robotics' humanoid robot. The firm is developing an entertainment robot in the same range than the AIBO robot : a companion robot. The process of mechanical prototyping, actuator designation, electronic architecture and first computing design are presented in this document.

Multidimensional feedforward compensator for industrial systems through pole assignment regulator and observer

Abstract: A feedforward-compensator-design technique is presented for industrial control systems. The proposed feedforward compensator can improve dynamic characteristics of multidimensional systems by modifying the input signals. The multidimensional feedforward-compensator design is based on the pole assignment regulator, the minimal-order observer, and the conversion from a closed-loop system to an open-loop system. The effectiveness of the proposed feedforward compensator is demonstrated by a simulation study of temperature control of a thermal power plant and by experiments of the contour control of an articulated robot arm.

Robotic manipulators with remotely-actuated joints: implementation using drive-shafts and u-joints

Abstract: A popular configuration for the actuation of robotic manipulators with articulated joints is to have motors directly attached to the joints. This approach does not involve any transmission elements between the actuators and the joints and it is advantageous in many respects. However, in certain cases this configuration may not be appropriate and manipulators with remotely-actuated joints may be desirable. In this article different alternatives for the implementation of remote actuation would be discussed and a case study would be presented relevant to a robotic arm, which was designed to operate inside a closed cylindrical magnetic resonance imaging (MRI) scanner for the performance of image-guided interventions. The transfer of motion to the articulated joints of the arm was implemented using drive shafts and universal joints (u-joints). Experimental testing of the arm highlights issues relevant to remote actuation

Articulated arm robot

Abstract: To increase the safety of an articulated arm robot with robot members connected by means of joints as open kinematics and with functional elements acting on the joints, such as drive motors, gears, brakes and a weight balance system, while reducing the mechanical limitations of the motion space of the robot, the present invention provides that at least some of the said functional elements have a dual design.