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At least 253 records · Page 14

A simulator application of a 'hands-on throttle and stick' concept to a transport pilot/autopilot interface

This paper presents the initial experiences garnered in applying a multifunction control strategy, based on the U.S. Air Force's 'Hands-On Throttle-and-Stick' concept for fighter aircraft to a transport aircraft simulator. The multifunction control strategy involves the activation of various flight system/subsystem operations (such as guidance and control, communication, and navigation functions) by use of menu displays and throttle and stick switches. The initial application of this multifunction control (MFC) concept was developed around a pilot/autopilot interface, contrasting a conventional, dedicated autopilot interface to an MFC implementation. The simulator characteristics and autopilot functions, as well as the conventional interface and MFC hardware/software, which were utilized in the application, are described herein. Initial pilot reaction and suggested improvements to this particular implementation are discussed. The paper terminates with a glance at plans for improvements and future applications based on the outcome of this initial study.

Busquets, A. M.↗

Application of computer image enhancement techniques to shuttle hand-held photography

With the advent of frequent Space Transportation System Shuttle missions, photography from hyperaltitudes stands to become an accessible and convenient resource for scientists and environmental managers. As satellite products (such as LANDSAT) continue to spiral in costs, all but the most affluent consumer is finding Earth imagery from space to be more and more unavailable. Therefore, the potential for Shuttle photography to serve a wide variety of users is increasing. However, despite the popularity of photos from space as public relations tools and report illustrations, little work has been performed to prove their scientific worth beyond that as basic mapping bases. It is the hypothesis of this project that hand-held Earth photography from the Space Shuttle has potentially high scientific merit and that primary data can be extracted. In effect, Shuttle photography should be considered a major remote sensing information resource.

David, B. E.↗

Transverse acceleration of oxygen ions by electromagnetic ion cyclotron resonance with broad band left-hand polarized waves

Central plasma sheet (CPS) ion conics are oxygen-dominated, with peak energies ranging from tens to hundreds of eV centered around pitch-angles between 115 and 130 degrees. Because of the lack of correlation between the CPS conics and the observed currents and/or electron beam-like structures, it is not likely that all of these conics are generated by interactions with electrostatic ion cyclotron waves or lower hybrid waves. Instead, it is suggested that the observed intense broad band electric field fluctuations in the frequency range between 0 and 100 Hz can be responsible for the transverse energization of the ions through cyclotron resonance heating with the left-hand polarized electromagnetic waves. This process is much more efficient for heating the oxygen ions than hydrogen ions, thus providing a plausible explanation of the oxygen dominance in CPS conics. Simple algebraic expressions are given from which estimates of conic energy and pitch angle can be easily calculated. This suggested mechanism can also provide some preheating of the oxygen ions in the boundary plasma sheet (BPS) where discrete aurorae form.

Chang, T.↗

Adapting a Robot Hand to Specialized Functions

Adaptor enables mechanical and electrical connections made easily between special-purpose end effector and arm of robot or remote mainpulator. Use in prosthetic devices also contemplatd. With adaptor, hand changed quickly from device designed to grasp objects of various sizes and shapes to device intended to do specific task efficiently.

Clark, Keith H.↗

Hand trigger system for bi-lateral gripping control in teleoperation

A device for human operator control of a robotic gripper has been developed and preliminary evaluation has been performed. The JPL Force Reflecting Hand Trigger system features an instrumented index finger trigger with load cell detection of finger force, a servo-controlled, lead-screw-driven backdrive capability by which the trigger's position can be made to follow that of the remotely controlled gripper, and a novel feedback mechanism by which clamping force or some other signal can be fed back by a swiveling motion, also servo-controlled, of the trigger surface (force reflection). This system has undergone preliminary testing in which the amount of force reflection is varied and dynamic force-tracking response is observed.

Fiorini, Paolo↗

Robot hands and extravehicular activity

Extravehicular activity (EVA) is crucial to the success of both current and future space operations. As space operations have evolved in complexity so has the demand placed on the EVA crewman. In addition, some NASA requirements for human capabilities at remote or hazardous sites were identified. One of the keys to performing useful EVA tasks is the ability to manipulate objects accurately, quickly and without early or excessive fatigue. The current suit employs a glove which enables the crewman to perform grasping tasks, use tools, turn switches, and perform other tasks for short periods of time. However, the glove's bulk and resistance to motion ultimately causes fatigue. Due to this limitation it may not be possible to meet the productivity requirements that will be placed on the EVA crewman of the future with the current or developmental Extravehicular Mobility Unit (EMU) hardware. In addition, this hardware will not meet the requirements for remote or hazardous operations. In an effort to develop ways for improving crew productivity, a contract was awarded to develop a prototype anthromorphic robotic hand (ARH) for use with an extravehicular space suit. The first step in this program was to perform a a design study which investigated the basic technology required for the development of an ARH to enhance crew performance and productivity. The design study phase of the contract and some additional development work is summarized.

Marcus, Beth↗

Concept development of a tendon arm manipulator and anthropomorphic robotic hand

AMETEK/ORED inhouse research and development efforts leading toward a next-generation robotic manipulator arm and end-effector technology is summarized. Manipulator arm development has been directed toward a multiple-degree-of-freedom, flexible, tendon-driven concept referred to here as a Tendon Arm Manipulator (TAM). End-effector development has been directed toward a three-fingered, dextrous, tendon-driven, anthropomorphic configuration which is referred to as an Anthropomorphic Robotic Hand (ARH). Key technology issues are identified for both concepts.

Tolman, C. T.↗

A new six-degree-of-freedom force-reflecting hand controller for space telerobotics

A new 6 degree of freedom universal Force Reflecting Hand Controller (FRHC) was designed for use as the man-machine interface in teleoperated and telerobotic flight systems. The features of this new design include highly intuitive operation, excellent kinesthetic feedback, high fidelity force/torque feedback, a kinematically simple structure, mechanically decoupled motion in all 6 DOF, good back-drivability, and zero backlash. In addition, the new design has a much larger work envelope, smaller stowage volume, greater stiffness and responsiveness, and better overlap of the human operator's range of motion than do previous designs. The utility and basic operation of a new, flight prototype FRHC called the Model X is briefly discussed. The design heritage, general design goals, and design implementation of this advanced new generation of FRHCs are presented, followed by a discussion of basic features and the results of initial testing.

Mcaffee, Douglas↗

Prosthetic Hand Lifts Heavy Loads

Prosthetic hand designed to enable amputee to lift diverse heavy objects like rocks and logs. Has simple serrated end effector with no moving parts. Prosthesis held on forearm by system of flexible straps. Features include ruggedness, simplicity, and relatively low cost.

Carden, James R.↗

Rotationally Actuated Prosthetic Hand

Prosthetic hand attached to end of remaining part of forearm and to upper arm just above elbow. Pincerlike fingers pushed apart to degree depending on rotation of forearm. Simpler in design, simpler to operate, weighs less, and takes up less space.

Norton, William E.↗

Compact Force-Reflecting Hand Controller

Novel design keeps joints mechanically independent. Force-reflecting hand controller for remote manipulator offers two times work volume of any of its predecessors. Folded into volume half that of its immediate predecessor for storage. First six-degree-of-freedom, cable-driven controller designed with six revolute joints; contains no prismatic joints. Advantages of low friction, low inertia, and no backlash. Intended for use in telerobotic experiments during space flight, controller modified for such terrestrial applications as construction and handling of dangerous (e.g., hot, poisonous, radioactive, or infectious) materials.

Snow, Edward R.↗

A new active virtual pivot six-degree-of-freedom hand controller for aerospace applications

During 1989 a new six-degree-of-freedom (6-DOF) active hand controller concept was designed and constructed based on the concept of a virtual pivot. This concept, labeled VPHC, was first demonstrated in a 1985 study and a patent was issued in 1990. Operator control input occurs via a force/torque sensor rigidly mounted to the handgrip. Sensed force/torque signals are used by microprocessors to generate motor drive control for each of six independently controlled motors mounted on the three-legged mechanism. The control microprocessor uses input biasing and rate-feedback motor controllers to generate the sensed feel of virtual springs and deadbands found in more conventional designs. An important advantage of this design is that the location of the virtual pivots, reflective forces and torques, breakout force levels, sensed spring rates, and operating modes, can be changed simply by changing the software. This approach yields an autonomous VPHC that can easily adapt itself to an individual operator (by software extension). A proof-of-concept version has been demonstrated, and further improvements are currently being studied and implemented.

Marshall, William C.↗

Comparison of hand laid-up tape and filament wound composite cylinders and panels with and without impact damage

Experimentally determined axial compressive failure loads, strains and failure modes of composite flat panels and cylinders are presented. A comparison of two types of filament wound flat graphite-epoxy panels indicates that the winding pattern can influence structural response. A comparison of hand laid-up tape and filament wound composite cylinders indicates that fabrication method may not significantly influence the failure mode or average failure strain of thick-walled (radius-to-thickness ratio less than 15) graphite-epoxy cylinders. The interaction of manufacturing-induced features (fiber cross-overs) and low-speed impact damage for graphite-epoxy specimens is also presented. Filament would flat panels with many fiber cross-overs exhibited lower failure strains than filament wound panels without fiber cross-overs for all impact speeds examined. Graphite-thermoplastic cylinders exhibited a significantly different failure mode from the graphite-epoxy cylinders.

Jegley, Dawn C.↗

Portable Computer Keyboard For Use With One Hand

Data-entry device held in one hand and operated with five fingers. Contains seven keys. Letters, numbers, punctuation, and cursor commands keyed into computer by pressing keys in various combinations. Device called "data egg" used where standard typewriter keyboard unusable or unavailable. Contains micro-processor and 32-Kbyte memory. Captures text and transmits it to computer. Concept extended to computer mouse. Especially useful to handicapped or bedridden people who find it difficult or impossible to operate standard keyboards.

Friedman, Gary L.↗

Hand-Switch Unit For Use With Protective Suit

Unit containing two hand-operated switches water-tight and designed for use with protective suit. One switch is toggle switch used to select communication by wire or radio. Other switch is press-to-talk button. User grasps and operates switches without looking at them. Fences on top of new unit protects toggle switch from inadvertent operation and spaced to accommodate gloved thumb. Push-to-talk button protected by longitudinal bar, springy and compressed inward to actuate button.

Chalson, Howard E.↗

Prosthetic helping hand

A prosthetic device for below-the-elbow amputees, having a C-shaped clamping mechanism for grasping cylindrical objects, is described. The clamping mechanism is pivotally mounted to a cuff that fits on the amputee's lower arm. The present invention is utilized by placing an arm that has been amputated below the elbow into the cuff. The clamping mechanism then serves as a hand whenever it becomes necessary for the amputee to grasp a cylindrical object such as a handle, a bar, a rod, etc. To grasp the cylindrical object, the object is jammed against the opening in the C-shaped spring, causing the spring to open, the object to pass to the center of the spring, and the spring to snap shut behind the object. Various sizes of clamping mechanisms can be provided and easily interchanged to accommodate a variety of diameters. With the extension that pivots and rotates, the clamping mechanism can be used in a variety of orientations. Thus, this invention provides the amputee with a clamping mechanism that can be used to perform a number of tasks.

Vest, Thomas W.↗

Hand controller study of force and control mode

The objectives are to compare and evaluate the utility and effectiveness of various input control devices, e.g., hand controllers, with respect to the relative importance of force and operation control mode (rate or position) for Space Station Freedom (SSF) related tasks. The topics are presented in viewgraph form and include the: Intelligent Research Systems Lab (ISRL) experimental design; Telerobotic Systems Research Laboratory (TSRL) final experimental design; and factor analysis summary of results.

A Terry Morris↗

Prosthetic Hand With Two Gripping Fingers

Prosthetic hand developed for amputee who retains significant portion of forearm. Outer end of device is end effector including two fingers, one moved by rotating remaining part of forearm about its longitudinal axis. Main body of end effector is end member supporting fingers, roller bearing assembly, and rack-and-pinion mechanism. Advantage of rack-and-pinion mechanism enables user to open or close gap between fingers with precision and force.

Norton, William E.↗