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in creator/contributor: "Feddema, J. T."

open access

Visual Servoing: A technology in search of an application

Considerable research has been performed on Robotic Visual Servoing (RVS) over the past decade. Using real-time visual feedback, researchers have demonstrated that robotic systems can pick up moving parts, insert bolts, apply sealant, and guide vehicles. With the rapid improvements being made in computing and image processing hardware, one would expect that every robot manufacturer would have a RVS option by the end of the 1990s. So why aren`t the Fanucs, ABBs, Adepts, and Motomans of the world… more

Date: May 1, 1994

Creator: Feddema, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Kinematically optimal robot placement for minimum time coordinated motion

This paper describes an algorithm for determining the optimal placement of a robotic manipulator within a workcell for minimum time coordinated motion. The algorithm uses a simple principle of coordinated motion to estimate the time of a joint interpolated motion. Specifically, the coordinated motion profile is limited by the slowest axis. Two and six degree of freedom (DOF) examples are presented. In experimental tests on a FANUC S-800 arm, the optimal placement of the robot can improve cycle … more

Date: October 1, 1995

Creator: Feddema, J.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A capacitance-based proximity sensor for whole arm obstacle avoidance

This paper addresses the issue of collision avoidance in unknown or partially modeled environments using a capacitive sensor. An eight channel capacitance-based sensor system which can detect obstacles up to 400 mm (16 inches) away has been developed. This sensor can detect both conductive and non-conductive obstacles of arbitrary color and shape. The sensor hardware is reliable and inexpensive, and it may be fabricated using flexible printed circuit boards to provide whole-arm and joint protec… more

Date: January 1, 1991

Creator: Novak, J.L. & Feddema, J.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Whole arm obstacle avoidance for teleoperated robots

This paper describes a collision avoidance system using Whole Arm Proximity (WHAP) sensors on a PUMA 560 robot arm. The capacitance-based sensors generate electric fields which can completely encompass the robot arm and detect obstacles as they approach from any direction. The directional obstacle information gathered by the WHAP sensors together with the sensor geometry and robot configuration is used to scale the commanded joint velocities of the robot. A linearized relationship between the W… more

Date: October 1, 1993

Creator: Feddema, J. T. & Novak, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Generic data acquisition system for robotic waste characterization

This paper describes a generic data acquisition system for robotic characterization of DOE production facilities and waste sites. While the specific suite of characterization sensors on the end of a robotic arm or vehicle will depend on site needs, many of the data acquisition, display, archival and interpretation requirements of the sites are common. Therefore, the objective is to create a generic, reusable computing and data acquisition system which can accept a multitude of sensors. This pap… more

Date: July 1, 1993

Creator: Feddema, J. T. & Spletzer, B. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Probability of Detection for Cooperative Sensor Systems

In this paper, the authors quantify how communication increases the effective range of detection of unattended ground sensors. Statistical analysis used to evaluate the probability of detection for multiple sensors using one, two, and infinite levels of cooperation. levels of cooperation are defined as the levels of communication between sensors. One level of cooperation means that one sensor passes its state information to several other sensors within a limited communication range, but this in… more

Date: March 26, 1999

Creator: Feddema, J.T. & Spletzer, B.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Parallel Assembly of LIGA Components

In this paper, a prototype robotic workcell for the parallel assembly of LIGA components is described. A Cartesian robot is used to press 386 and 485 micron diameter pins into a LIGA substrate and then place a 3-inch diameter wafer with LIGA gears onto the pins. Upward and downward looking microscopes are used to locate holes in the LIGA substrate, pins to be pressed in the holes, and gears to be placed on the pins. This vision system can locate parts within 3 microns, while the Cartesian manip… more

Date: March 4, 1999

Creator: Christenson, T.R. & Feddema, J.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Optimal trajectories for flexible-link manipulator slewing using recursive quadratic programming: Experimental verification

Procedures for trajectory planning and control of flexible link robots are becoming increasingly important to satisfy performance requirements of hazardous waste removal efforts. It has been shown that utilizing link flexibility in designing open loop joint commands can result in improved performance as opposed to damping vibration throughout a trajectory. The efficient use of link compliance is exploited in this work. Specifically, experimental verification of minimum time, straight line track… more

Date: September 1, 1994

Creator: Parker, G. G.; Eisler, G. R. & Feddema, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ultra-Precise Assembly of Micro-Electromechanical Systems (MEMS) Components

This report summarizes a three year effort to develop an automated microassembly workcell for the assembly of LIGA (Lithography Galvonoforming Abforming) parts. Over the last several years, Sandia has developed processes for producing surface machined silicon and LIGA parts for use in weapons surety devices. Some of these parts have outside dimensions as small as 100 micron, and most all have submicron tolerances. Parts this small and precise are extremely difficult to assembly by hand. Therefo… more

Date: April 1, 1999

Creator: Feddema, J.T.; Simon, R.; Polosky, M. & Christenson, T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Knowledge assistant: A sensor fusion framework for robotic environmental characterization

A prototype sensor fusion framework called the {open_quotes}Knowledge Assistant{close_quotes} has been developed and tested on a gantry robot at Sandia National Laboratories. This Knowledge Assistant guides the robot operator during the planning, execution, and post analysis stages of the characterization process. During the planning stage, the Knowledge Assistant suggests robot paths and speeds based on knowledge of sensors available and their physical characteristics. During execution, the Kn… more

Date: December 1, 1996

Creator: Feddema, J.T.; Rivera, J.J. & Tucker, S.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development and Application of Genetic Algorithms for Sandia's RATLER Robotic Vehicles

No Description Available.

Date: November 1, 2000

Creator: Barnette, D. W.; Pryor, R. J. & Feddema, J. T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Experiments in micromanipulation and CAD-driven microassembly

This paper discusses recent experiments in the manipulation and assembly of parts with 100 micron outside dimensions and submicron tolerances. The objective of this work is to develop a micromanipulation workcell which can automatically assemble LIGA (Lithography Galvonoforming Abforming) parts using an assembly plan and a CAD drawing of each of the components. The workcell consists of an AdeptOne robot, precision stages, long distance microscope, and a high aspect ratio modeled polysilicon twe… more

Date: October 1, 1997

Creator: Feddema, J. T.; Keller, C. G. & Howe, R. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CAD-driven microassembly and visual servoing

This paper describes current research and development on a robotic visual servoing system for assembly of LIGA (Lithography Galvonoforming Abforming) parts. The workcell consists of an AMTI robot, precision stage, long working distance microscope, and LIGA fabricated tweezers for picking up the parts. Fourier optics methods are used to generate synthetic microscope images from CAD drawings. These synthetic images are used off-line to test image processing routines under varying magnifications a… more

Date: March 10, 1998

Creator: Feddema, J.T. & Simon, R.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Assembly planning at the micro scale

This paper investigates a new aspect of fine motion planning for the micro domain. As parts approach 1--10 {micro}m or less in outside dimensions, interactive forces such as van der Waals and electrostatic forces become major factors which greatly change the assembly sequence and path plans. It has been experimentally shown that assembly plans in the micro domain are not reversible, motions required to pick up a part are not the reverse of motions required to release a part. This paper develops… more

Date: May 14, 1998

Creator: Feddema, J.T.; Xavier, P. & Brown, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Collision avoidance during teleoperation using whole arm proximity sensors coupled to a virtual environment

Much of the current robotics effort at the US DOE is directed toward remote handling of hazardous waste. Telerobotic systems are being developed to remotely inspect, characterize, and process waste. This paper describes a collision avoidance system using Whole Arm Proximity (WHAP) sensors on an articulated robot arm. The capacitance-based sensors generate electric fields which completely encompass the robot arm and detect obstacles as they approach from any direction. The robot is moved through… more

Date: August 1, 1993

Creator: Novak, J. L.; Feddema, J. T.; Miner, N. E. & Stansfield, S. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Efficient Control Law Simulation for Multiple Mobile Robots

In this paper we consider the problem of simulating simple control laws involving large numbers of mobile robots. Such simulation can be computationally prohibitive if the number of robots is large enough, say 1 million, due to the 0(N2 ) cost of each time step. This work therefore uses hierarchical tree-based methods for calculating the control law. These tree-based approaches have O(NlogN) cost per time step, thus allowing for efficient simulation involving a large number of robots. For concr… more

Date: October 6, 1998

Creator: Driessen, B. J.; Feddema, J. T.; Kotulski, J. D. & Kwok, K. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Decentralized fuzzy control of multiple nonholonomic vehicles

This work considers the problem of controlling multiple nonholonomic vehicles so that they converge to a scent source without colliding with each other. Since the control is to be implemented on simple 8-bit microcontrollers, fuzzy control rules are used to simplify a linear quadratic regulator control design. The inputs to the fuzzy controllers for each vehicle are the (noisy) direction to the source, the distance to the closest neighbor vehicle, and the direction to the closest vehicle. These… more

Date: September 1, 1997

Creator: Driessen, B. J.; Feddema, J. T. & Kwok, K. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Miniature Autonomous Robotic Vehicle (MARV)

Sandia National Laboratories (SNL) has recently developed a 16 cm{sup 3} (1 in{sup 3}) autonomous robotic vehicle which is capable of tracking a single conducting wire carrying a 96 kHz signal. This vehicle was developed to assess the limiting factors in using commercial technology to build miniature autonomous vehicles. Particular attention was paid to the design of the control system to search out the wire, track it, and recover if the wire was lost. This paper describes the test vehicle and … more

Date: December 31, 1996

Creator: Feddema, J. T.; Kwok, K. S.; Driessen, B. J.; Spletzer, B. L. & Weber, T. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Minimum-time trajectory control of a two-link flexible robotic manipulator

This paper analyzes the experimental and simulation results of a minimum-time trajectory control scheme for a two-link flexible robot. An off-line optimization routine determines a minimum-time, straight line tip trajectory which stays within the torque constraints of the motors and ends in a quiescent state, i.e., no vibrational transients. An efficient finite-element model is used in the optimization to approximate the flexible arm dynamics. The control strategy described here is used to dete… more

Date: January 1, 1990

Creator: Schoenwald, D.A.; Feddema, J.T.; Eisler, G.R. & Segalman, D.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Explaining finite state machine characteristics using variable structure control

This paper describes how variable structure control can be used to describe the overall behavior of multiple autonomous robotic vehicles with simple finite state machine rules. The importance of this result is that it allows for the design of provably asymptotically stable group behaviors from a set of simple control laws and appropriate switching points with variable structure control. The ability to prove convergence to a goal is especially important for applications such as locating military… more

Date: October 1, 1997

Creator: Feddema, J. T.; Robinett, R. D. & Driessen, B. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Designing stable finite state machine behaviors using phase plane analysis and variable structure control

This paper discusses how phase plane analysis can be used to describe the overall behavior of single and multiple autonomous robotic vehicles with finite state machine rules. The importance of this result is that one can begin to design provably asymptotically stable group behaviors from a set of simple control laws and appropriate switching points with decentralized variable structure control. The ability to prove asymptotically stable group behavior is especially important for applications su… more

Date: March 10, 1998

Creator: Feddema, J. T.; Robinett, R. D. & Driessen, B. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Techniques for controlling a two-link flexible arm

The long length and relatively small cross sectional area of the robotic arms envisioned for use inside of the underground nuclear waste storage tanks will require the control of flexible structures. This will become an important problem in the characterization and remediation of these tanks. We are developing control strategies to actively damp residual vibrations in flexible robotic arms caused by high speed motion and abrupt external forces. A planar, two-link flexible arm is currently being… more

Date: January 1, 1990

Creator: Feddema, J.T.; Eisler, G.R.; Segalman, D.J.; Robinett, R.D. III; Morimoto, A.K. & Schoenwald, D.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department