Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Arms Control”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Sensory-Feedback Exoskeletal Arm Controller

An electromechanical exoskeletal arm apparatus has been designed for use in controlling a remote robotic manipulator arm. The apparatus, called a force-feedback exoskeleton arm master (F-EAM) is comfortable to wear and easy to don and doff. It provides control signals from the wearer s arm to a robot arm or a computer simulator (e.g., a virtual-reality system); it also provides force and torque feedback from sensors on the robot arm or from the computer simulator to the wearer s arm. The F-EAM enables the wearer to make the robot arm gently touch objects and finely manipulate them without exerting excessive forces. The F-EAM features a lightweight design in which the motors and gear heads that generate force and torque feedback are made smaller than they ordinarily would be: this is achieved by driving the motors to power levels greater than would ordinarily be used in order to obtain higher torques, and by providing active liquid cooling of the motors to prevent overheating at the high drive levels. The F-EAM (see figure) includes an assembly that resembles a backpack and is worn like a backpack, plus an exoskeletal arm mechanism. The FEAM has five degrees of freedom (DOFs) that correspond to those of the human arm: 1. The first DOF is that of the side-to-side rotation of the upper arm about the shoulder (rotation about axis 1). The reflected torque for this DOF is provided by motor 1 via drum 1 and a planar four-bar linkage. 2. The second DOF is that of the up-and-down rotation of the arm about the shoulder. The reflected torque for this DOF is provided by motor 2 via drum 2. 3. The third DOF is that of twisting of the upper arm about its longitudinal axis. This DOF is implemented in a cable remote-center mechanism (CRCM). The reflected torque for this DOF is provided by motor 3, which drives the upper-arm cuff and the mechanism below it. A bladder inflatable by gas or liquid is placed between the cuff and the wearer s upper arm to compensate for misalignment between the exoskeletal mechanism and the shoulder. 4. The fourth DOF is that of flexion and extension of the elbow. The reflected torque for this DOF is provided by motor 4 and drum 4, which are mounted on a bracket that can slide longitudinally by a pin-and-slot engagement with the upper-arm cuff to compensate for slight variations in the position of the kinematic center of the elbow. Attached to drum 4 is an adapter plate to which is attached a CRCM for the lower arm. 5. The lower-arm CRCM implements the fifth DOF, which is the twist of the forearm about its longitudinal axis. Motor 5 provides the reflected torque for this DOF by driving the lower-arm cuff. A rod transmits twist and torsion between the lower-arm cuff and the hand cuff. With this system, the motion of the wearer s joints and the reflected torques applied to these joints can be measured and controlled in a relatively simple manner. This is because the anthropomorphic design of the mechanism imitates the kinematics of the human arm, eliminating the need for kinematic conversion of joint-torque and joint-angle data.

An, Bin↗
DOE OSTI2023

Beyond New START: Two Forecasts for Future Russian-US Arms Control

A world without the New START Treaty (NST) or treaty-based strategic arms control cannot simply be categorised as ‘unacceptable’.1 That world is possible. It has been increasing in likelihood for some time and thus it must be both understood and anticipated. Furthermore, the NST will expire on 5 February 2026 and it could disappear much sooner, depending on the actions of either Russia or the United States. No amount of positive thinking on the value of strategic arms control or talking points about the importance of the treaty can change its status as a hostage in the broader bilateral relationship.

Political science↗
DOE OSTI2021

Nonproliferation and Arms Control Research and Development (NPAC R&D) [Slides]

NPAC R&D focus areas include: Advancing U.S. capabilities to detect and characterize nuclear weapon development activities globally, including material production, the movement of special nuclear materials and nuclear weapons, and the testing or use of nuclear weapons, Supporting the development and testing of policy options and technical capabilities for international nuclear safeguards, arms control / treaty verification, nuclear export controls, and nonproliferation initiatives consistent with U.S. Government goals and objectives to enable monitoring and verification, Utilizing uranium, lithium, and high explosives (HE) materials expertise to support national-level activities in nuclear forensics and nuclear detection technology testing and evaluation, Providing unique training and capacity-building programs, particularly with the Nuclear Detection and Sensor Testing Center (NDSTC), and Engaging internationally to promote nonproliferation and arms control norms and best practices through bilateral and multilateral work.

36 MATERIALS SCIENCE↗
DOE OSTI2024

US Perspectives on the Conventional/Nuclear Interactions and the Impacts on Nuclear Escalation Risks and Future Arms Control Prospects

This short paper is organized around a few discrete questions. How have U.S. perspectives on conventional and nuclear interactions evolved in recent years? How have these changing perspectives shaped U.S. thinking on perceived nuclear escalation risks with Russia, both long standing and newly emerged? And finally, what do these U.S. perceptions of interactions and risks mean for future potential arms control either in the conventional or nuclear arena? The answers to these questions appear to show some promise for future work in this area. Conventional and nuclear interactions are increasing, and thus the two domains cannot be kept as deliberately or artificially separated as in the past. There is a growing mutual recognition regarding the interplay between conventional and nuclear capabilities in the strategic stability equation. There is also an increasingly shared recognition in the United States and Russia that nuclear escalation risks are likely to originate in conventional crises or conflict, placing an imperative on some form of conflict prevention procedures at the lower end of the spectrum. This requirement suggests some potential areas for risk reduction measures outside of those traditionally considered in conventional and nuclear arms control over the past several decades.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2019

Arms Control Opportunities for Inherently Safe and Secure Nuclear Command, Control, and Communications

The Department of Defense Science Board has stated that the United States is "not prepared to defend againsr cyber-attacks and that the military could lose "trust in the information and ability to control U.S. systems and forces [including nuclear forces]." One potential weak spot in cyber-security is storing encryption keys in computer memory. This paper explores the use of hardware devices (so-called Physical Unclonable Functions, or PUFs) to generate, in the nuclear weapon itself, unique encryption keys each time they are needed. Not only do we find that this has the potential to mitigate a number of cyberthreats, but such hardware has the potential to greatly diminish the total uncertainty associated with radiation-based warhead authentication procedures; a procedure many analysts feel will be key to future arms control regimes. After outline the use of PUFs in nuclear command, control, and communications--and indicating some of the areas that still require further research--we discuss their application to arms control and warhead authentication

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
NASA NTRS1993

The application of active side arm controllers in helicopters

Eurocopter Deutschland (ECD) started simulation trials to investigate the particular problems of Side Arm Controllers (SAC) applied to helicopters. Two simulation trials have been performed. In the first trial, the handling characteristics of a 'passive' SAC and the basic requirements for the application of an 'active' SAC were evaluated in pilot-in-the-loop simulations, performing the tasks in a realistic scenario representing typical phases of a transport mission. The second simulation trial investigated the general control characteristics of the 'active' in comparison to the 'passive' control principle. A description of the SACs developed by ECD and the principle of the 'passive' and 'active' control concept is given, as well as specific ratings for the investigated dynamic and ergonomic parameters effecting SAC characteristics. The experimental arrangements, as well as the trials procedures of both simulation phases, are described and the results achieved are discussed emphasizing the advantages of the 'active' as opposed to the 'passive' SAC concept. This also includes the presentation of some critical aspects still to be improved and proposals to solve them.

Knorr, R.↗
DOE OSTI2019

Highlights of the Quad Multilateral Nuclear Arms Control Research Initiative LETTERPRESS Simulation

The US, UK, Sweden and Norway have formed the Quad Nuclear Verification Partnership and have been working together as the ‘Quad’ to ensure non-nuclear weapon states (NNWS) and nuclear weapon states (NWS) participate to overcome the challenge of nuclear arms control verification. The Quad aims to complement and inform the work of other multinational initiatives such as the International Partnership for Nuclear Disarmament Verification (IPNDV). The initial engagement of the Quad was the development and execution of a role-playing, in-field verification simulation, named LETTERPRESS. A benefit of role-playing events is the capacity they have to allow researchers to engage critically with a challenge from multiple perspectives. This paper will introduce LETTERPRESS and the process the Quad followed to develop and execute the multilateral simulation. The paper will highlight the in-play objectives of the verification regime, the site hosting the on-site inspection, and the verification technologies and their roles with respect to the objectives. The paper will include lessons learned from LETTERPRESS, focusing on the in-play objectives and technologies and their contribution to a successful monitoring result. The paper will conclude by highlighting the in-play success of a multilateral verification body and the ability of both NNWS and NWS to contribute to the verification process within LETTERPRESS.

arms control, Quad, LETTERPRESS↗
DOE OSTI2024

Developing an intrinsically secure information barrier for arms control verification through machine learning

Near-term solutions are needed to allow for flexible engagement in future nuclear arms control discussions. This project developed a method for implementing an information barrier (IB) on commercial systems, shortening the research and development lifecycle for warhead verification technologies while offering improved and inherently flexible capabilities. The crux of the verification challenge remains the difficulty in developing an authenticatable IB which prevents sensitive host country information from inadvertent transmission to an inspector. Many concepts for IB’s rely on dedicated “trusted” processor modules developed with dedicated custom radiation detection systems and associated algorithms. Without a priori knowledge of the treaty item, the parameter space for measurements can be nearly infinite and robustness against spoofing without the ability to view sensitive data is key. This project has produced an unclassified framework capable of ingesting data from common gamma detectors and identifying the presence of weapons grade nuclear material at over 90% accuracy.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2014

Nuclear Arms Control, Nonproliferation, and Counterterrorism: Impacts on Public Health

Reducing the risks of nuclear war, limiting the spread of nuclear weapons and reducing global nuclear weapons stockpiles are key national and international security goals. They are pursued through a variety of international arms control, nonproliferation and counter-terrorism treaties and agreements. These legally binding and political commitments, together with the institutional infrastructure that supports them, work to establish global norms of behavior and have limited the spread of weapons of mass destruction. Beyond the primary security objectives, reducing the likelihood of the use of nuclear weapons, preventing environmental releases of radioactive material, increasing the availability of safe and secure nuclear technology for peaceful purposes, and providing scientific data relevant to predicting and managing the consequences of natural or human-caused disasters world-wide provide significant benefits to global public health.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2025

Demonstration and Concept of Operations for a Zero-Knowledge Protocol Passive Imaging Measurement for Arms Control

Here, we present an imaging system that employs zero-knowledge protocols to protect sensitive geometrical information, along with procedures to increase confidence in the result. The goal of this work is to enable the inclusion of warhead confirmation measurements in future arms control treaties. We present a demonstration of both true positive and true negative measurements that validate models and establish authenticating procedures toward meeting acceptance requirements for use in nuclear facilities. We use a two-dimensional time-encoded fast neutron imaging system with an anti-symmetric mask pattern; the fast neutron count values exceeding minimum or maximum thresholds indicate that two measured items are not identical. Laboratory measurements over twenty trials show that alarm rates for negative confirmation measurements are within uncertainties of model predictions. Positive confirmation measurements indicate that alarm rates are large enough to encourage treaty compliance.

Sweany, Melinda Dominique [Sandia National Laborat↗
NASA NTRS1983

The manned maneuvering unit flight controller arm

The Manned Maneuvering Unit (MMU) and its support equipment provide an extravehicular astronaut mobility, and the ability to work outside the confines of the Shuttle Orbiter payload bay. The MMU design requirements are based on the highly successful Skylab M-509 maneuvering unit. Design of the MMU was started as an R&D effort in April 1975 and Flight Hardware design was started in August 1979 to support a possible requirement for in-space inspection and repair of Orbiter thermal protection tiles. Subsequently, the qualification test and production activities were slowed, and the current projected earliest first flight is now STS-11 in January, 1984. The MMU propulsion subsystem provides complete redundancy with two identical "system". Each system contains a high pressure gaseous nitrogen tank, an isolation valve, a regulator, and twelve 1.7 lbf (7.5 N) thrusters. The thrusters are packaged to provide the crew member six-degree-of-freedom control in response to commands from translational and rotational hand controllers. This paper discusses the MMU control arm requirements, design, and developmental history.

Falkner, K. E.↗
NASA NTRS1982

Some piloting experiences with multifunction isometric side-arm controllers in a helicopter

The installation of two side-arm mounted, isometric controllers in the NAE Airborne Simulator, a modified, variable stability Bell 205 A is described, as is the development of various control systems for use with them. The results of two experiments are presented indicating both the feasibility and acceptability of such systems for a wide variety of tasks in a conventional single rotor helicopter, with a minimum of stability augmentation. Areas of future research are indicated.

Morgan, J. M.↗
NASA NTRS1983

Dynamic analysis for robot arm control

Explicit state equations provide detailed analytic insight into the dynamic behavior of a robot arm and facilitate the understanding of the control problem. The analytic strength of explicit state equations is exemplified for a given robot arm. In fact, for the quoted example, the explicit and exact state equations involve considerably less computation than the use of the known most efficient general-purpose computational algorithm for robot arm dynamics.

Bejczy, A. K.↗
NASA NTRS1989

Test and validation for robot arm control dynamics simulation

The Flight Telerobotic Servicer (FTS) program will require an ability to develop, in a cost effective manner, many simulation models for design, analysis, performance evaluation, and crew training. Computational speed and the degree of modeling fidelity associated with each simulation must be commensurate with problem objectives. To demonstrate evolving state-of-the-art general purpose multibody modeling capabilities, to validate these by laboratory testing, and to expose their modeling shortcomings, two focus problems at the opposite ends of the simulation spectrum are defined: (1) Coarse Acquisition Control Dynamics. Create a real time man-in-the-control-loop simulator. Provide animated graphical display of robot arm dynamics and tactile feedback sufficient for cueing the operator. Interface simulator software with human operated tactile feedback controller; i.e., the Kraft mini-master. (2) Fine, Precision Mode Control Dynamics. Create a high speed, high fidelity simulation model for the design, analysis, and performance evaluation of autonomous 7 degree-of-freedom (DOF) trajectory control algorithms. This model must contain detail dynamic models for all significant dynamics elements within the robot arm, such as joint drive mechanisms.

Yae, K. Harold↗
NASA NTRS1991

Effect of motor dynamics on nonlinear feedback robot arm control

A nonlinear feedback robot controller that incorporates the robot manipulator dynamics and the robot joint motor dynamics is proposed. The manipulator dynamics and the motor dynamics are coupled to obtain a third-order-dynamic model, and differential geometric control theory is applied to produce a linearized and decoupled robot controller. The derived robot controller operates in the robot task space, thus eliminating the need for decomposition of motion commands into robot joint space commands. Computer simulations are performed to verify the feasibility of the proposed robot controller. The controller is further experimentally evaluated on the PUMA 560 robot arm. The experiments show that the proposed controller produces good trajectory tracking performances and is robust in the presence of model inaccuracies. Compared with a nonlinear feedback robot controller based on the manipulator dynamics only, the proposed robot controller yields conspicuously improved performance.

Tarn, Tzyh-Jong↗
NASA NTRS1988

Load balancing and closed chain multiple arm control

The authors give the general dynamical equations for several rigid link manipulators rigidly grasping a commonly held rigid object. It is shown that the number of arm-configuration degrees of freedom lost due to imposing the closed-loop kinematic constraints is the same as the number of degrees of freedom gained for controlling the internal forces of the closed-chain system. This number is equal to the dimension of the kernel of the Jacobian operator which transforms contact forces to the net forces acting on the held object, and it is shown that this kernel can be identified with the subspace of controllable internal forces of the closed-chain system. Control of these forces makes it possible to regulate the grasping forces imparted to the held object or to control the load taken by each arm. It is shown that the internal forces can be influenced without affecting the control of the configuration degrees of freedom. Control laws of the feedback linearization type are shown to be useful for controlling the location and attitude of a frame fixed with respect to the held object, while simultaneously controlling the internal forces of the closed-chain system. Force feedback can be used to linearize and control the system even when the held object has unknown mass properties. If saturation effects are ignored, an unconstrained quadratic optimization can be performed to distribute the load optimally among the joint actuators.

Kreutz, Kenneth↗
NASA NTRS1997

Mars Surveyor '98 MVACS Robotic Arm Control System Design Concepts

This paper describes the control system design concepts for the Mars Volatiles and Climate Surveyor (MVACS) Robotic Arm which supports the scientific investigations to be conducted as part of the Mars Surveyor '98 Lander project. Novel solutions are presented to some of the unique problems encountered in this demanding space application with its tight constraints on mass, power, volume, and computing power.

control manipulator Mars robot trajectory 4-DOF↗