Engineering topics
Publications and source records attributed to Fernandez, Ken.
This viewgraph presentation reviews the collaboration in developing robotic and autonomous systems by NASA and the Department of Defense (DoD). Several examples of the collaboration are reviewed.
This viewgraph presentation describes the collaborative effort of NASA and the US Army on unmanned systems. The contents include: 1) Robotic/Autonomous Systems Architecture Development; 2) Synergy In Robotics/Autonomous Systems Development; 3) Surface Mobility Systems: Lunar Pylon Network Project; 4) Lunar Pylon Network Enables Multiple Vehicle Operations & Logistics; 5) Surface Mobility Systems: MARCbot IV-N Project Overview; 6) Autonomous Logistics Support Demonstration; and 7) Lunar Network Demonstration and Collaborative Effort.
Collection of computer programs being developed to assist engineers in allocating tolerances to dimensions of components and assemblies. System reflects tolerancing expertise of design and manufacturing engineers; helps engineers maintain comprehensive tolerancing policy and overview that might otherwise get lost when attending to details of design and manufacturing processes. Necessary to allocate tolerances for three main reasons: tolerances allow for variations in dimensions of components as manufactured; assembly of two or more components, dimensions lie between specified limits; and part replaced must fit in place.
ROBOSIM, a simulator for robotic systems, was developed by NASA to aid in the rapid prototyping of automation. ROBOSIM has allowed the development of improved robotic systems concepts for both earth-based and proposed on-orbit applications while significantly reducing development costs. In a cooperative effort with an area university, ROBOSIM was further developed for use in the classroom as a safe and cost-effective way of allowing students to study robotic systems. Students have used ROBOSIM to study existing robotic systems and systems which they have designed in the classroom. Since an advanced simulator/trainer of this type is beneficial not only to NASA projects and programs but industry and academia as well, NASA is in the process of developing this technology for wider public use. An update on the simulators's new application areas, the improvements made to the simulator's design, and current efforts to ensure the timely transfer of this technology are presented.
Control algorithm satisfies several welding-process requirements simultaneously. Report discusses part of control concept for downhand-welding system. (In downhand welding, parts to be welded and welding head always oriented to keep face of weld as nearly horizontal as possible so gravitation helps to keep molten metal in joint.) Presents mathematical basis of control algorithm for computer-aided design/computer-aided manufacturing system performing downhand welding.
The use of computer graphic simulation techniques to resolve critical design and operational issues for robotic systems is described. Use of this technology will result in greatly improved systems and reduced development costs. The major design issues in developing effective robotic systems are discussed and the use of ROBOSIM, a NASA developed simulation tool, to address these issues is presented. Three representative simulation case studies are reviewed: off-line programming of the robotic welding development cell for the Space Shuttle Main Engine; the integration of a sensor to control the robot used for removing the Thermal Protection System from the Solid Rocket Booster; and the development of a teleoperator/robot mechanism for the Orbital Maneuvering Vehicle.
Computer program ROBOSIM, developed to simulate operations of robots, applied to preliminary design of robotic arc-welding operation. Limitations on equipment investigated in advance to prevent expensive mistakes. Computer makes drawing of robotic welder and workpiece on positioning table. Such numerical simulation used to perform rapid, safe experiments in computer-aided design or manufacturing.
A generalized method for controlling a six degree-of-freedom (DOF) robot and a two DOF positioner used for arc welding operations is described. The welding path is defined in the part reference frame, and robot/positioner joint angles of the equivalent eight DOF serial linkage are determined via an iterative solution. Three algorithms are presented: the first solution controls motion of the eight DOF mechanism such that proper torch motion is achieved while minimizing the sum-of-squares of joint displacements; the second algorithm adds two constraint equations to achieve torch control while maintaining part orientation so that welding occurs in the downhand position; and the third algorithm adds the ability to control the proper orientation of a wire feed mechanism used in gas tungsten arc (GTA) welding operations. A verification of these algorithms is given using ROBOSIM, a NASA developed computer graphic simulation software package design for robot systems development.
A robot simulation system, has been developed to perform automation and robotics system design studies. The system uses a procedure-oriented solid modeling language to produce a model of the robotic mechanism. The simulator generates the kinematics, inverse kinematics, dynamics, control, and real-time graphic simulations needed to evaluate the performance of the model. Simulation examples are presented, including simulation of the Space Station and the design of telerobotics for the Orbital Maneuvering Vehicle.
This paper describes the use of computer graphic simulation techniques to resolve critical design and operational issues for robotic systems. Use of this technology will result in greatly improved systems and reduced development costs. The major design issues in developing effective robotic systems are discussed and the use of ROBOSIM, a NASA developed simulation tool, to address these issues is presented. Three representative simulation case studies are reviewed: off-line programming of the robotic welding development cell for the Space Shuttle Main Engine (SSME); the integration of a sensor to control the robot used for removing the Thermal Protection System (TPS) from the Solid Rocket Booster (SRB); and the development of a teleoperator/robot mechanism for the Orbital Maneuvering Vehicle (OMV).
This paper describes the use of computer graphic simulation techniques to resolve critical design and operational issues for robotic systems used for on-orbit operations. These issues are robot motion control, robot path-planning/verification, and robot dynamics. The major design issues in developing effective telerobotic systems are discussed, and the use of ROBOSIM, a NASA-developed computer graphic simulation tool, to address these issues is presented. Simulation plans for the Space Station and the Orbital Maneuvering Vehicle are presented and discussed.