Showing papers in "Journal of Robotic Systems in 1986"
TL;DR: A prototype omnidirectional vision system and the implementation of the navigation techniques using this modern sensor and an advanced automatic image processor is described, ushering in a new and novel approach—dynamic omniddirectional vision for mobile robots and autonomous guided vehicles.
Abstract: Mobile robotic devices hold great promise for a variety of applications in industry. A key step in the design of a mobile robot is to determine the navigation method for mobility control. The purpose of this paper is to describe a new algorithm for omnidirectional vision navigation. A prototype omnidirectional vision system and the implementation of the navigation techniques using this modern sensor and an advanced automatic image processor is described. The significance of this work is in the development of a new and novel approach—dynamic omnidirectional vision for mobile robots and autonomous guided vehicles.
97 citations
TL;DR: Concurrent algorithms for robot navigation in unexplored terrain are presented and the need for an efficient data structure to store an obstacle terrain model in order to reduce traversal time, and also to incorporate learning is revealed.
Abstract: Navigation planning is one of the most vital aspects of an autonomous mobile robot. Robot navigation for completely known terrain has been solved in many cases. Comparatively less research dealing with robot navigation in unexplored obstacle terrain has been reported in the literature. In recent times this problem has been addressed by adding learning capability to a robot. The robot explores terrain using sensors as it navigates, and builds a terrain model in an incremental manner. In this article we present concurrent algorithms for robot navigation in unexplored terrain. The performance of the concurrent algorithms is analyzed in terms of planning time, travel time, scanning time, and update time. The analysis reveals the need for an efficient data structure to store an obstacle terrain model in order to reduce traversal time, and also to incorporate learning. A modified adjacency list is proposed as a data structure for storing a spatial graph that represents an obstacle terrain. The time complexities of the algorithms that access, maintain, and update the spatial graph are estimated, and the effectiveness of the implementation is illustrated.
40 citations
TL;DR: A new multivariable controller is introduced in this article to achieve command matching and is designed on the basis of a linearized model of the robot dynamics.
Abstract: Several simple multivariable controllers such as proportional (P), proportional-derivative (PD), proportional-integral (PI), and proportional-integral-derivative (PID) are investigated and designed for stabilization and regulation of a two-link planar robot. A new multivariable controller is introduced in this article to achieve command matching. The multivariable controllers are designed on the basis of a linearized model of the robot dynamics. Numerous simulation results are presented to evaluate the performance of the multivariable controllers for the two-link planar robot.
30 citations
TL;DR: This work presents an approach which interfaces the real-time operation of the robot with an intelligent subsystem that performs error analysis and forward recovery if a failure occurs.
Abstract: Modern computer-controlled robots typically fail at their tasks whenever they encounter an error, no matter how minor. The physical environment of a typical assembly robot is too unstructured to benefit from conventional software approaches to reliability. We present an approach which interfaces the real-time operation of the robot with an intelligent subsystem that performs error analysis and forward recovery if a failure occurs. Our approach involves a special representation of the robot's program that efficiently tracks the robot's operation in real time and is easy to modify to include automatically generated recovery procedures.
27 citations
TL;DR: This paper deals with a new type of proximity sensor which has the capability of measuring spatial information, such as gap distance, inclination angles, and the angular positions of object particles.
Abstract: A proximity sensor is defined as the noncontact sensor of end-effector, and is one of the most important sensors for robot control. This paper deals with a new type of proximity sensor which has the capability of measuring spatial information, such as gap distance, inclination angles, and the angular positions of object particles. The measuring principle of the sensor is based on the phase shift of a modulated light signal. For this purpose, six light sources are placed on a cross-shaped pattern that is centered by a photodetector, and the power of light sources are modulated by different phase sine wave signals. The distance and angles can be measured by investigating the received phase information at the predetermined emitting pattern. By experimental measurement, the characteristics of this sensor are obtained and the effectiveness of the sensor is confirmed.
24 citations
TL;DR: The reduced position vector is defined and the dynamic model formed so as to allow the calculation of both the relative motion with respect to the constraint and the reactions, of the constraint.
Abstract: This article deals with the dynamics of closed kinematic chains obtained from open ones by introducing some constraints upon the motion of the last segment. Such problems apear very often in practical manipulator operation (writing task, assembling, etc.). The reduced position vector is defined and the dynamic model formed so as to allow the calculation of both the relative motion with respect to the constraint and the reactions, of the constraint. Impact problems are discussed also. Finally, a surface-type constraint is considered.
22 citations
TL;DR: A generic experimental system that implemented the activity controller theory, which has the ability to coordinate any number of robots and to respond to the random arrival of components, so as to efficiently assemble various mixes of products.
Abstract: This article describes a generic experimental system that implemented the activity controller theory. The controller has the ability to coordinate any number of robots (and other automated machines) and to respond to the random arrival of components, so as to efficiently assemble various mixes of products. The work also briefly presents the structure of the coordination system, and a solution frame to the dynamic collision avoidance problem. The computer-controlled experimental system is used to simultaneously operate two robots sharing tasks and auxiliary devices in an assembly cell.
17 citations
TL;DR: Two types of miniaturized optical range-sensing methods have been developed, which projects an axially symmetrical light sheet onto an object and a ring pattern is produced, and thus the information of partial inclination can be obtained.
Abstract: Two types of miniaturized optical range-sensing methods have been developed. The first is called RORS (Riken Optical Range-Sensing Scheme). In this method, a mirror tunnel is first placed between an objective lens and an object to be measured; a bright spot is then projected onto the object through the objective lens. This spot is observed through the objective lens after reflection with the mirror tunnel, and range information is determined by the triangulation. The width of an optical system can be reduced remarkably smaller than the effective base line length of the triangulation. Therefore, it is suitable to miniaturize a range-sensing system such as an optical stylus and a proximity sensor. The second method, RORST (Riken Optical Range Sensing Method for Surface Tracing), projects an axially symmetrical light sheet onto an object and a ring pattern is produced. The ring pattern image is then projected onto the observation plane by the objective lens, radii of the ring pattern image for different azimuths are detected, distances corresponding to the specified azimuths are determined by the triangulation, and thus the information of partial inclination can be obtained.
16 citations
TL;DR: Experimental results show that the newly developed method make object shape recognition easy and inexpensive, and application experiment proved that the method is effective for manipulator work due to its provision of distance information.
Abstract: This article describes a three-dimensional shape recognition method that employs an ultrasonic distance sensor mounted on a manipulator, and its application to a manipulator control system. The principle of the method is to reconstruct an object surface numerically using both distance and orientation informations of an object. The method makes it possible to control the manipulator, to set the sensor in any position and orientation employing freedom of the manipulator, and to measure the object. The method is available for manipulator control because it can precisely assess the distance from the manipulator to the object, as well as reconstruct the object shape. Experimental results show that the newly developed method make object shape recognition easy and inexpensive. Application experiment proved that the method is effective for manipulator work due to its provision of distance information.
12 citations
TL;DR: The logical specification of a microprocessor-based air-servo-controlled robot hand is presented, as well as its actual implementation, which includes position and force feedback and a considerable cost saving is achieved by not changing the gripper itself.
Abstract: The logical specification of a microprocessor-based air-servo-controlled robot hand is presented, as well as its actual implementation. This hand can accommodate a wide variety of workpieces and allows for flexible assembly through the use of an automatic quick-change fingertip. The changeable set of gripper fingers is equipped with sensors, including a tactile force sensor, a crossfire sensor, a proximity sensor, and a slip sensor. A changeable set of gripper fingers with different sensing ranges can cope with certain subranges of the workpiece spectrum. A considerable cost saving is achieved by not changing the gripper itself. This specially designed hardware and software system includes position and force feedback. A PUMA 560 is used to test the success of the entire process.
11 citations
TL;DR: The adaptive self-tuning controller is outlined, based on a time series difference equation model in which the parameters are estimated on-line and the performance of the system designed is tested experimentally, and the results are presented.
Abstract: A picture of a scene is used to extract information for an adaptive control algorithm. The object of interest is first located by means of a classifier. The position and orientation of the object are determined from a binary picture. The desired path that the gripper of the manipulator is to follow is specified by discrete points, first in the Cartesian and then in the joint coordinate system. The adaptive self-tuning controller is outlined. The controller design is based on a time series difference equation model in which the parameters are estimated on-line. The gains of the controller are tuned so that a quadratic performance criterion is minimized. The performance of the system designed is then tested experimentally, and the results are presented.
TL;DR: The zero reference position method, proposed by Gupta in 1981, is based upon an arbitrary choice of thezero reference position, the principle of displacement similarity, and the hand-to-the-base sequence of changing the joint variables in a serial manipulator.
Abstract: The zero reference position method, proposed by Gupta in 1981, is based upon an arbitrary choice of the zero reference position, the principle of displacement similarity, and the hand-to-the-base sequence of changing the joint variables in a serial manipulator. Its applications in performing recursive computations, formulating explicit governing equations, and obtaining closed form solutions for serial manipulators are presented in this paper. A Bendix-type of industrial robot is used for illustrating the closed form solution procedure.
TL;DR: A new type of optical range sensor is being proposed as a robotic sensor that consists of the projection subsystem of an axially symmetrical light sheet and the detection subsystem for monitoring the focussing process of a lens.
Abstract: A new type of optical range sensor is being proposed as a robotic sensor. The range sensor consists of the projection subsystem of an axially symmetrical light sheet and the detection subsystem for monitoring the focussing process of a lens. The projection subsystem produces a bright ring pattern through an objective lens on the surface of an object. Next, the distance from the range sensor to the surface of an object is calculated from the position of the lens. The prototype range sensor is able to measure the distance in the range of 430 to 570 mm with an accuracy of 0.3 mm. As the position of the objective lens is controlled so that the ring pattern projected on the surface of an object becomes a fine spot, the detection subsystem finds the position of the objective lens on which the output of photodiode comes to be maximum.
TL;DR: The authors have developed a new displacement sensor using a wire of pseudoelastic titaniumnickel (Ti-Ni) alloy wire that exhibited good linearity between the strain and electric resistance.
Abstract: The authors have developed a new displacement sensor using a wire of pseudoelastic titaniumnickel (Ti-Ni) alloy wire. In the measurement, it was found that this alloy exhibited good linearity between the strain and electric resistance. This linearity has been generally applicable up to several percent strain. In addition, a repeat test and dynamic characteristics have been examined. From these results, it is concluded that this Ti-Ni alloy wire has a possible application as a displacement sensor. Its features include compactness, reduction in weight, and environment attack.
TL;DR: The effectiveness of IML was confirmed by actually making a robot perform some tasks programmed in IML, and it is shown that these functions can be realized with the unified representation by introducing the concept of a functional programming language.
Abstract: This article describes the motion-oriented robot language IML (interactive manipulator language) with the characteristic of a functional programming language. The main functions of IML are (1) It is possible to describe the iterative motions without using a loop. (2) The user-defined procedures (commands) can be called by specifying the command name. (3) It is possible to describe robot motion (a sequence of the position and orientation of a robot hand) and force magnitude in the task-oriented Cartesian coordinate system (task coordinate system) suitable for robot tasks. Furthermore, it is possible to describe the translation and rotation of the coordinate system without syntactic distinction. (4) As the teaching data can be easily embedded in the language and can be played back in the force control mode, complex task programming becomes easy. In IML, as the user-defined command and the teaching data can be used just as the builtin system command; the system can be extended easily and naturally. In this article these features are described, and it is shown that these functions can be realized with the unified representation by introducing the concept of a functional programming language. The effectiveness of IML was confirmed by actually making a robot perform some tasks programmed in IML.
TL;DR: A model of the human visual system, including eye movement, is made and the capacity in an artificial sensor, using the Neuron Simulator, which consists of sixty-four microprocessors is realized.
Abstract: Humans have two eyes and see objects binocularly. The three-dimensional sensing capacity of humans depends both on the eyes and the neuron system controlling them. In this article, we made a model of the human visual system, including eye movement, and tried to realize the capacity in an artificial sensor. For this, the visual system is separated into two parts—the Eye System and the Neuron System. The former is realized by the sensor mechanisms that are similar to human eyes and the latter by the Neuron Simulator which consists of sixty-four microprocessors. This system can be used as a passive three-dimensional sensor in unarranged surroundings such as the outdoors.
TL;DR: Four sets of exact solutions for the vector of the joint angles {θi} pertaining to the inverse kinematics problem of a standard 6-axis robot manipulator with two different kinds of gripper configurations are presented.
Abstract: Presented are four sets of exact solutions for the vector of the joint angles {θi} pertaining to the inverse kinematics problem of a standard 6-axis robot manipulator with two different kinds of gripper configurations. Here a standard 6-axis robot is meant to be a general computer-controlled revolute robot with base, shoulder, elbow, wrist pitch, wrist yaw, wrist roll, and gripping action.
Explicit solutions are obtained using Denavit-Hartenberg homogeneous transformations. Furthermore, the inverse solutions are examined by means of a direct kinematic computer program.
TL;DR: A new programming environment for the IBM 7535 robot is introduced, replaced by a hierarchical control scheme involving a host and a subservient robot and believed to be superior to the original language AML/E for the following reasons.
Abstract: A new programming environment for the IBM 7535 robot is introduced. AML/E is replaced by a hierarchical control scheme involving a host and a subservient robot. Application programs are developed on the host, an IBM-PC XT, in an extended version of the “C” programming language. These extensions allow an application program to be composed of several concurrent processes, one of which is responsible for commanding the robot. To configure the robot as a slave in this relationship, a new operating system was developed for its controller. Written in the same language employed at the host level, it is structured as four concurrent processes managing the robot's resources. An interprocess message-passing scheme provides a path for master/slave communication. The resultant environment is believed to be superior to the original language AML/E for the following reasons: Concurrency, along with the data and control structures of “C,” is made available to the application programmer. Communication is well structured. The robot's operating system is documented, written in a high-level language, and open to the user for modification. Due to the significance of integrating the robot into more complex applications involving sensors, these characteristics are felt to be essential in future robots.
TL;DR: The prototype of the RORS (Riken Optical Range Sensing Method) sensor was developed for use in noncontact robot sensor applications and is thus compact, low cost, and easily available.
Abstract: In an effort to develop a practical implementation of the RORS (Riken Optical Range Sensing Method), a prototype was developed. An evaluation was performed with this prototype in combination with an Integrated Circuit intended for use in an auto-focus camera. The sensor was developed for use in noncontact robot sensor applications and is thus compact, low cost, and easily available. This sensor system consists of a head section and a processing/display section. The size of the sensor head section is 16 mm in dia and 23.5 mm in length, and is capable of measuring the distance from top of the sensor head to a target in 0–6 mm range. The distance signal is obtained as a dc voltage of 90 mV/mm and a digital signal which divides the measuring range into eight levels is also available.
TL;DR: In an effort to improve CAD/CAM current circumstances, a trial CAE system which generates an operation path of a robot from a solid-model built-in CAD process, has been examined.
Abstract: CAD/CAM technologies have been developed and are beginning to penetrate rapidly into industries. At present, however, there are many problems that should be solved before CAD/CAM technologies can play their proper role in the total process. In an effort to improve CAD/CAM current circumstances, a trial CAE system which generates an operation path of a robot from a solid-model built-in CAD process, has been examined. In this system, solid models are built by performing set operations such as addition, subtraction, intersection between several primitives or solid models. Processing is made for a solid model represented by B-rep (boundary representation). To ease the processing, curved faces such as spherical, cylindrical, or conical surfaces, are approximated by several flat planes. As a first step, by assuming Gaussian spatial distribution for a painting gun, path planning of a painting robot for a convex solid body has been examined. A scanning plane is defined for each flat plane and a path of robot effector is generated on this plane.
TL;DR: This paper describes with examples of some typical industrial robots developed in Japan the process of development, which industrial robots in Japan took and describes the differences of cultural basis between Japan and western countries the influences of automation to man, culture and society.
Abstract: This paper describes with examples of some typical industrial robots developed in Japan the process of development, which industrial robots in Japan took. It also describes citing the differences of cultural basis between Japan and western countries the influences of automation to man, culture and society, and survey the future industrial robots.
TL;DR: An algorithm is presented for using a robot system with a single camera to position in threedimensional space a slender object for insertion into a hole; for example, an electrical pin-type termination into a connector hole.
Abstract: An algorithm is presented for using a robot system with a single camera to position in threedimensional space a slender object for insertion into a hole; for example, an electrical pin-type termination into a connector hole. The algorithm relies on a control-configured end effector to achieve the required horizontal translations and rotational motion, and it does not require camera calibration. A force sensor in each fingertip is integrated with the vision system to allow the robot to teach itself new reference points when different connectors and pins are used. Variability in the grasped orientation and position of the pin can be accommodated with the sensor system. Performance tests show that the system is feasible. More work is needed to determine more precisely the effects of lighting levels and lighting direction.
TL;DR: A new method is proposed to convert a contour model to a mesh surface model with minimum loss of contour line informations to decide mesh data on a mesh line where there are fewer points intersecting with contour lines.
Abstract: Contour line type representation is useful for understanding the surface structure qualitatively to a human. However, for the computer handling, a contour line model may not be suitable and it is required to be converted to the other type model such as a mesh surface model. It may be a problem how to decide mesh data on a mesh line where there are fewer points intersecting with contour lines. In this article, the authors propose a new method to convert a contour line model to a mesh surface model with minimum errors. Mesh lines (equivalent to the planes intersected with contour surface) located on the contour surface and intersected with contour lines are calculated. A mesh line which has maximum number of effective sampling points (that means maximum number of intersections with contour lines, and hereafter referred to as latter) is selected and a sectional shape along this mesh line is decided. The sectional shape is represented by spline curve with parameters, so that the mesh point data on the mesh line can be determined easily, and these decided mesh points are regarded as equivalent as intersection with contour lines. The above processes are repeated until all mesh lines which have intersection points or obtained mesh data have been chosen and calculated. Thus we can convert a contour model to a mesh surface model with minimum loss of contour line informations.
TL;DR: A new formulation of the robot model for control synthesis facilitates the synthesis of regulators for parameter variations using a robust servomechanism approach or a force feedback approach.
Abstract: The article addresses the control problem associated with tracking a trajectory which is predefined by the desired position and orientation of the end-effector tip (stage of nominal control). The problem is compounded by the assumption that variations in system parameters may occur thereby requiring that the nominal control be complemented with a controller (stage of perturbed control) which would regulate the disturbance produced by the variation in system parameters. A new formulation of the robot model for control synthesis is presented. The new formulation facilitates the synthesis of regulators for parameter variations using a robust servomechanism approach or a force feedback approach. The two approaches are illustrated using examples. The first example uses robust regulation to reject step input disturbances. The second example simulates the operation of peg-in-hole insertion using force feedback with an LQ controller.
TL;DR: A semiautomatic procedure to calibrate a robot manipulator for improving positioning accuracy is proposed using the point-pairs in the theoretical and actual coordinate frames based on a leastsquare method.
Abstract: A semiautomatic procedure to calibrate a robot manipulator for improving positioning accuracy is proposed. An error-correcting transformation is estimated using the point-pairs in the theoretical and actual coordinate frames. The theoretical points are obtained using a 3D model of the inspected part, whereas the actual points are derived with image processing and analytic geometry techniques. The estimation of the error-correcting transformation is based on a leastsquare method. Experimental results are described to illustrate the calibration procedure.