Search results

The purpose of this paper is to build a seven‐degrees of freedom (DOF) parallel‐serial robot system which has the advantage of mechanical novelty and simplicity compared with the existing platforms, and to share the experience of converting a popular motion base to an industrial robot for use in full‐mission tank training processes of three armored arms.

By studying the concept of the robot system, a novel parallel‐serial robot with seven DOF driven by electrical servo motors is built. And the transmission modules and Hooke joints are explored and designed in detail. Then the inverse kinematics based on coupling compensation and time‐jerk synthetic optimization methods for trajectory planning of the simulator are presented and further discussed in order to satisfy the requirements of high stability and perfect performance. In advance, the feasibility and applicability of this triune parallel‐serial robot system are verified.

A prototyped test shows that the performance of the system is of a satisfaction with real‐time tracking any trajectories given by the visual system smoothly. Finally, the characteristics of the robot system are realized and verified by experiments and an industrial application.

The triune full‐mission tank training simulator developed in this paper has been used in the military industry and it has a great potential application.

This successful usage of the novel and simple parallel robot system in the military industry expands the range of its applications in real‐life task more operators training. And the proposal methods of inverse kinematics based on coupling compensation and trajectory planning enhanced the theoretical research of the parallel robot.

Rediffusion Simulation and the Link‐Miles Division of the Singer Company (UK) Ltd. have been selected by the United Kingdom Ministry of Defence to develop and jointly produce four flight simulators for the F Mk 2 air defence variant of the Panavia Tornado. They will be used by the Royal Air Force to provide aircrew conversion and continuation training in the full‐mission role of the aircraft and its associated systems.

The purpose of this paper is to show the merit of using mission information in tuning the controller gains for Stewart manipulator instead of the generic inputs previously developed in literature.

The paper introduces two optimization techniques based on mission information. The first technique, a partial‐information technique, uses gain scheduling that applies different controllers for different mission tracks. The second technique, a full‐information technique uses a single robust controller by considering the full mission data. For demonstrating these techniques' feasibility, a nonlinear numerical simulation for a Stewart manipulator was built and tested using a generic mission. This mission consists of two piecewise trajectories (tracks). The proposed techniques were compared with one of the previous optimization techniques in literature, no‐information technique, in which a step response is used to search for optimal controller gains without any information about the mission. Genetic algorithms were used to search for the optimal controller gain in each case with different cost functions.

Based on the numerical simulations, the proposed mission‐based optimization techniques have superior performances compared with no‐information technique.

The proposed techniques were applied in a joint space or for a decentralized control. The work can be extended to be applied in a task space or for a centralized control.

The paper proposes two novel optimization techniques: partial‐ and full‐information techniques for tuning the controller gains of a Stewart manipulator, where mission information was imbedded into the cost function. These two techniques are generally applicable for other nonlinear systems such as aircraft stability and control augmentation systems.

FOR the past decade the case for simulator training has been based on the cost savings that can be achieved over training aircrew in actual aircraft.

This paper presents a new multi‐channel temperature measurement system (MCTMS) with small size, light weight and low power consumption for the microgravity fluid experiment of drop Marangoni migration on SZ‐4 spaceship, a test module of the manned space mission of China.

The MCTMS, with a commercial‐off‐the‐shelf (COTS) component monolithic thermocouple amplifier with cold junction compensation AD595, is designed to measure temperature gradient field of up to 6 type T thermocouples Cu‐Constantan for microgravity fluid experiment. Through an analog multiplexer, the very small signal amplitude of the six‐channel temperatures can be acquired and amplified by the same monolithic thermocouple amplifier to retain the consistency of the six channels. A fully mission analysis and evaluation on the COTS component was taken into account before it was used in the thermal and radiation environment of space.

Using the COTS component in space can increase the system performance and considerably reduce the size, weight, power consumption and the overall complexity of the system. The measurement resolution of the MCTMS reaches 0.1°C because of the utilization of the COTS with high performance. In addition, the transfer function of the AD595 was deduced for type T thermocouples.

This paper suggests an easy way of measuring temperature for microgravity fluid experiment on spacecraft. Using a COTS component on spacecraft, also, is a new practical case study, which is more suitable for on‐board implementation. The MCTMS, presented in this work, has run in‐orbit successfully on SZ‐4 spaceship and the experiment result in space is reported.

Performance Based Logistics (PBL) is an acquisition reform that is intended to improve weapon systems logistics by reducing cost, improving reliability, and reducing footprint. PBL is an extension of a broad process of rationalizing and, in many cases, outsourcing government services. As with other examples of governmental service outsourcing, measurement issues arise in the gap between governmental objectives and service measurement, and in the contrast between clear profit-centered vendor metrics, and more complex mission-oriented governmental metrics. Beyond this, however, PBL presents new challenges to the relationship between governmental agencies and their service vendors. In many cases, weapons systems logistical support involves levels of operational risk that are more difficult to measure and more difficult to value than other government services. We discuss the implications of operational risk and other measurement issues on PBL implementation.

TO MANY PEOPLE in the aeronautical world a flight simulator is a training device ranging in complexity from the old Link Trainer to the latest fully representative airline simulator, in which aircrew can practice operating procedures and emergencies at a fraction of the cost of airborne training, and without risk.

The training of commercial aircrews in team management is now being recognised as a priority. This article reviews one major intervention with Trans Australia Airlines.

The development of the flight station of the C‐130J variant of the C‐130 military airlift aircraft is discussed. The development effort began with research and development projects in the early 1980s. Following this was a series of related research and technology integration efforts under contract to the US Government in the late 1980s and early 1990s. Finally, detailed design of the C‐130J in a formal development program began in 1992. The technologies that were integrated into the C‐130J flight station that made it possible to reduce the flight station crew from four (pilot, copilot, navigator, and flight engineer) to two (pilot and copilot) are reviewed.

Heralding a new era in the leisure aviation market was the arrival early in February at Luton International Airport of Britannia Airways' new Boeing 767—the first in Europe.