Il-Hong Suh

An intelligent coordinated control system for steering and traction of electric vehicles

An intelligent coordinated control system is designed for the active steering and the left/right traction force distribution control of 2-wheel-drive and 2-wheel-steering (2WD/2WS) electric vehicles, where input-output linearization is employed. Also, a fuzzy-rule-based cornering force estimator is suggested to avoid using an uncertain highly nonlinear expression, and a neural network compensator is additionally utilized for the estimator to correctly find cornering force. With these techniques, the proposed control system is shown by simulation results to be robust against drastic change of the external environments such as road conditions.

Resolved motion control of redundant robot manipulators by neural optimization networks

An effective resolved motion control method of redundant manipulators is proposed to minimize the energy consumption and to increase the dexterity while satisfying the physical actuator constraints. The method employs the neural optimization networks, where the computation of Jacobian matrix is not required. Specifically, end-effector movement resulting from each joint differential motion is first separated into orthogonal and tangential components with respect to a given desired trajectory. Then the resolved motion is obtained by neural optimization networks in such a way that: (1) the linear combination of the orthogonal components should be null; (2) the linear combination of the tangential components should be the differential length of the desired trajectory; (3) the differential joint motion limit is not violated, and (4) the weighted sum of the square of each differential joint motion is minimized. The weighting factors are controlled by a newly defined joint dexterity measure as the ratio of the tangential and orthogonal components.<<ETX>>

Automatic assembly for microelectronic components

The design and development of an automatic assembly machine for microelectronic components is described. The machine uses multiple microprocessors to accomplish its tasks, which include process supervision, visual pattern recognition, and information display. The system is flexible and reliable due to its modular design and the use of a structured supervisor with diagnosis capability. It minimizes manual operation by means of automatic measurements and corrects object orientation and component size with the aid of a vision system. The control system was implemented in real time on a laboratory semiconductor die bonding machine. In a test, it was possible to reduce the bonding cycle time to 0.8 s/die (0.8-7.0 mm/sup 2/ sized die). >

Design and implementation of a dual-arm robot control system with multi-sensor integrating capability

An intelligent robotic system was developed for effectively controlling dual robot arms. The control system aids collision avoidance and coordination of the dual arms. The system has a multi-sensor integration capability. It responds to environmental sensors such as a vision sensor, a force sensor and a position encoder. The control system permits the human operator to communicate with the system via a teach box, a high-level language with a screen editor and menu-driven operational commands, which were specially designed for multiarm control. The control system was applied successfully to the assembly system using two SCARA type robot arms.<<ETX>>

A Multi-Microprocessor-Based Control System for Assembly of Electronic Components

Abstract Design experiences of a project on building a multi-microprocessor-based automation control system for the assembly of electronic components is reported in this paper. The control system consists of four subsystems, which are the supervisory controller, the visual pattern recognition system, the display unit and the servo system. The emphasis was put on the design of a fast, cost-effective visual information-processing unit. For this, a new type of frame grabber together with noise-insensitive image processing algorithms are incorporated by employing the TMS 4161 dual ported memory. To verify the proposed design concepts, an experimental control system is developed and applied for the semiconductor die-bonding machine.

A Handheld 3-Dimensional Motion Tracking Device for Ubiquitous Computing Environment

This paper describes a design experience of a low-cost 6 DOF spatial tracker system where relative low accuracy and relatively long ranges, wireless communication will be achieved by means of low cost accelerometers and gyros with contemporary microprocessor. However, there are two key problems; one is the bias drift problem and the other is that single or double integration of acceleration signal suffers not only from noise but also from nonlinear effects caused by gravity. To be specific, beginning and stopping of hand motions needs to be accurately detected to initiate and terminate integration process to get position and pose of the hand from accelerometer and gyro signals, since errors due to noise and/or hand-shaking motions accumulated by integration processes. Several experimental results are shown to validate our proposed algorithms.

A Sweeping Path Planner for a Smearing Robot

Abstract This paper presents a sweeping path planner for a free navigating service robot. The planner generates a sweeping path pattern by the proposed five basic procedures. This algorithm recognizes obstacles on an architectural CAD draft and generates tracking points as subgoals, which are used to make the area filling paths. A sweeping path is planned by sequentially connecting the tracking points in such a way that (1) the connected line segments should not be crossed, (2) the total tracking points should be as short as possible, and (3) a tracking line should not pass through the obstacle. Feasibility of the developed techniques has been demonstrated on a real architectural CAD draft.

Development of a Task-Level Assembly Planning System Using Dual Arms

Abstract In this paper, it is proposed that a task-level assembly planning system that consists of Object Data Base(ODB) generator, Target Data Base(TDB) generator, and Task-Level Command Interpreter(TCI). ODB generator provides the information on the dimensions of each part to be assembled. Considering the information of ODB and the assembly sequence of the target object given by 3D GUI environment, TDB generator finds an optimal path of each assembling part while avoiding obstacles. TCI generates a set of primitive robot control commands for the robot to follow the path planned by TDB, where a collision avoidance scheme for dual arms is also considered. Then, these primitive commands are downloaded to our dual-arm control system to perform the given assembly task. To show the validity of our proposed planning system, an assembly work building a house with 13 Lego blocks is demonstrated.

Experimental validation of distributed recovery block

Presents the experimental validation of distributed execution of recovery blocks, in short distributed recovery blocks (DRB). The experiment was conducted on a tightly coupled network (TCN) and a time-critical application was used as a testbed for the experiment. The concept of the DRB is the combination of distributed processing and RB (recovery block). It is also an approach for unified treatment of both hardware and software faults. The primary objective of this experiment was to demonstrate the efficiency of the DRB scheme in a tightly coupled real-time distributed computing environment. This experiment required employing the DRB scheme in an application program and measuring its impact on the system performance. The main interest in measurements is to find the time overhead of the DRB scheme, i.e., the overhead of the error detection and recovery activity.<<ETX>>

A fuzzy logic based bin picking technique

A novel two-dimensional matched filter of the parallel jaw type using fuzzy logic is proposed for bin-picking. Specifically, averaged pixel intensity of the windowed region for the filtering is considered to be fuzzy. Also membership functions for darkness and brightness are designed by using the intensity histogram of an image. A rule is then given to know how much a windowed region can be a possible hold site. Eight rules determine the part orientation, where Mamdanis reasoning method is applied. To show the validity of the proposed technique, some experimental results are illustrated and compared with the results of the conventional matched filtering technique.<<ETX>>