Efficiency Of Today Research Articles

Dynamic simulation and neural network compliance control of an intelligent forging center

Automation of forging processes is important for both safety and efficiency in today's advanced manufacturing operations. This work supports the development of an Intelligent Open Die Forging System which will integrate state-of-the-art modelling techniques, automatic die selection and sequencing, full system dynamic simulation, automatic machine programming and coordination, and sensor-based process control to enable the production of more general and complex workpiece geometries than are achievable using current forging methods. Effective automation of this open die forging system requires the coordination and control of the major system components: press, robot, and furnace. In particular, forces exerted on the robot through its manipulation of the workpiece during forging must be minimized to avoid damage to the manipulator mechanism. In this paper, the application of neural networks for compliance control of the forging robot to minimize these forces is investigated. Effectiveness of the neural network-based compliance control module is evaluated through a full dynamic system simulation, which will later form a central part of the complete Intelligent Forging System. Dynamic simulation of the robot is achieved using an efficient O(N) recursive algorithm, while material flow of the workpiece is modeled with a finite element approach. Simulation and timing results for the complete processing system for a specific open die forging example are presented.

Alternative engines for road vehicles

Spark-ignition engines and compression-ignition diesel engines have been almost unchallenged as power units for road vehicles for the last century. However, the air pollution problems which they cause, and their poor efficiency in today's typical operating conditions, make it essential that alternatives to these engines are fully explored. Many have been proposed, but few have been exploited commercially. This book discusses the technologies that presently exist for alternative engines. For each alternative engine that is considered, the operating principle is discussed, together with the primary advantages and disadvantages of the particular technology. The development of each alternative is noted and current manufacturer research and experimental testing is described, together with results where available. The alternative engines and prospects for further development of conventional engines are discussed and compared with reference to fuel economy and exhaust emissions. Cost issues are made generally, with definitive data provided where it exists. This book forms part of a programme of study on the contribution of road transport to global warming and air pollution, and investigating ways of reducing it.

Materials for a New Generation of Vehicles

ABSTRACTThe Partnership for a New Generation of Vehicles (PNGV) is a national initiative with three goals: First, to significantly improve national competitiveness in manufacturing; second, to implement commercially viable innovations from ongoing research on conventional vehicles, and third, to develop a vehicle to achieve up to three times the fuel efficiency of today's comparable vehicle (ie, the 1994 Chrysler Concorde, Ford Taurus, and Chevrolet Lumina). Note this vehicle will have the equivalent customer purchase price of today's vehicles adjusted for economics, while meeting the customers' needs for quality, performance, and utility. Eight federal agencies are currently contributing to these goals, as well as the three principal US automobile manufacturers, numerous automotive component suppliers, research laboratories, and universities.Materials research and development is a significant effort within PNGV. The goals in this area include development of lightweight, recyclable materials for structural applications, high strength, long-life, high temperature materials for engine components, improved materials for alternative propulsion and energy storage systems, and cost-effective process technologies and component fabrication methods. Application of advanced materials to automobiles will involve consideration of diverse factors, including weight savings, affordability, recyclability, crashworthiness, repairability, and manufacturability.