22,980 research outputs found
Design of a five-axis ultra-precision micro-milling machine—UltraMill. Part 1: Holistic design approach, design considerations and specifications
High-accuracy three-dimensional miniature components and microstructures are increasingly in demand in the sector of electro-optics, automotive, biotechnology, aerospace and information-technology industries. A rational approach to mechanical micro machining is to develop ultra-precision machines with small footprints. In part 1 of this two-part paper, the-state-of-the-art of ultra-precision machines with micro-machining capability is critically reviewed. The design considerations and specifications of a five-axis ultra-precision micro-milling machine—UltraMill—are discussed. Three prioritised design issues: motion accuracy, dynamic stiffness and thermal stability, formulate the holistic design approach for UltraMill. This approach has been applied to the development of key machine components and their integration so as to achieve high accuracy and nanometer surface finish
Adaptive servo control for umbilical mating
Robotic applications at Kennedy Space Center are unique and in many cases require the fime positioning of heavy loads in dynamic environments. Performing such operations is beyond the capabilities of an off-the-shelf industrial robot. Therefore Robotics Applications Development Laboratory at Kennedy Space Center has put together an integrated system that coordinates state of the art robotic system providing an excellent easy to use testbed for NASA sensor integration experiments. This paper reviews the ways of improving the dynamic response of the robot operating under force feedback with varying dynamic internal perturbations in order to provide continuous stable operations under variable load conditions. The goal is to improve the stability of the system with force feedback using the adaptive control feature of existing system over a wide range of random motions. The effect of load variations on the dynamics and the transfer function (order or values of the parameters) of the system has been investigated, more accurate models of the system have been determined and analyzed
First Steps Towards an Ethics of Robots and Artificial Intelligence
This article offers an overview of the main first-order ethical questions raised by robots and Artificial Intelligence (RAIs) under five broad rubrics: functionality, inherent significance, rights and responsibilities, side-effects, and threats. The first letter of each rubric taken together conveniently generates the acronym FIRST. Special attention is given to the rubrics of functionality and inherent significance given the centrality of the former and the tendency to neglect the latter in virtue of its somewhat nebulous and contested character. In addition to exploring some illustrative issues arising under each rubric, the article also emphasizes a number of more general themes. These include: the multiplicity of interacting levels on which ethical questions about RAIs arise, the need to recognise that RAIs potentially implicate the full gamut of human values (rather than exclusively or primarily some readily identifiable sub-set of ethical or legal principles), and the need for practically salient ethical reflection on RAIs to be informed by a realistic appreciation of their existing and foreseeable capacities
Ambiguous Bodies, Biopower and the Ideologies of Science Fiction
Contemporary Hollywood film narrates the fear of monstrous science; attending to the
modulations of medicine, capital and the body. The filmic body is employed to illustrate the
power of the new biotechnologies to create and sustain life and the new sets of social relations
which are a consequence of the marriage of capital and medicine. In the Hollywood film,
persons who do not fit the ideal healthy persona have a moral duty to pursue repair and
transformation. Constructed as inherently lacking, the unhealthy body becomes a repository
for social anxieties about control and vulnerability, vis-à-vis the enormous and exponentially
expanding science and technology fields. Hierarchies of embodiment are played out on the Big
Screen as imperfect bodies are excluded from public life, power and status and urged to strive
for “optimization”. Late modern societies present the possibility of new technologies which
have the potential to radicalize bodies. However, these potential modulations are ultimately
derived from a set of ideologies around the body and the power of the individual to enact an
individualized solution. Contemporary narratives circulate around ownership of capital and
the price of “repair.” This marriage of science and capital in popular narratives may be
indicative of concerns for our future, as the power to make and repair life seems to rest
increasingly in the hands of an elite
SHARC: Space Habitat, Assembly and Repair Center
Integrated Space Systems (ISS) has taken on the task of designing a Space Habitat, Assembly and Repair Center (SHARC) in Low Earth Orbit to meet the future needs of the space program. Our goal is to meet the general requirements given by the 1991/1992 AIAA/LORAL Team Space Design competition with an emphasis on minimizing the costs of such a design. A baseline structural configuration along with preliminary designs of the major subsystems was created. Our initial mission requirements, which were set by AIAA, were that the facility be able to: support simultaneous assembly of three major vehicles; conduct assembly operations and minimal extra vehicular activity (EVA); maintain orbit indefinitely; and assemble components 30 feet long with a 10 foot diameter in a shirtsleeve environment
- …