国内精品♨️_成人性生交A片免费看武则天_.手.动.输.入.网.址.联.系.客.服.人.员.lanan_shell
American Institute of Aeronautics and Astronautics 1 AIAA-2001-0127 Development of the Black Widow Micro Air Vehicle Joel M. Grasmeyer* and Matthew T. Keennon† AeroVironment, Inc. 4685-3H Industrial St. Simi Valley, CA 93063 This paper describes the development of the Black Widow Micro Air Vehicle (MAV) over the past 4 years. An MAV has generally been defined as having a span of less than 6 inches, and a mass of less than 100 grams. The Black Widow is a 6-inch span, fixed-wing aircraft with a color video camera that downlinks live video to the pilot. It flies at 30 mph, with an endurance of 30 minutes, and a maximum communications range of 2 km. The vehicle has an autopilot, which features altitude hold, airspeed hold, heading hold, and yaw damping. The electronic subsystems are among the smallest and lightest in the world, including a 2- gram camera, a 2-gram video downlink transmitter, and a 5-gram fully proportional radio control system with 0.5-gram actuators. A Multidisciplinary Design Optimization methodology with a genetic algorithm was used to integrate the MAV subsystems and optimize the vehicle for maximum endurance. Some of the potential missions for MAVs are visual reconnaissance, situational awareness, damage assessment, surveillance, biological or chemical agent sensing, and communications relay. In addition to these military missions, there are several commercial applications, such as search and rescue, border patrol, air sampling, police surveillance, and field research. Introduction* The first feasibility study for Micro Air Vehicles (MAVs) was performed by the RAND Corporation in 1993.1 The authors indicated that the development of insect-size flying and crawling systems could help give the US a significant military advantage in the coming years. During the following two years, a more detailed study was performed at Lincoln Laboratory.2 This study resulted in a DARPA workshop on MAVs in 1995. In the fall of 1996, DARPA funded further MAV studies under the Small Business Innovation Research (SBIR) program. AeroVironment performed a Phase I study, which concluded that a six-inch MAV was feasible. In the spring of 1998, AeroVironment was awarded a Phase II SBIR contract, which resulted in the current Black Widow MAV configuration. Several universities have also been involved in MAV research. Competitions have been held since 1997 at the University of Florida and Arizona State University. The goals of the competitions have been to observe a target located 600 m from the launch site and to keep a two-ounce payload aloft for at least 2 minutes. *AeroMechanical Engineer, Member AIAA †Program Manager Copyright © 2001 by Joel M. Grasmeyer. Published by the American Institute of Aeronautics and Astronautics, Inc. with permission. Early Prototypes In the early stages of the Black Widow MAV program, several prototypes were built to explore the 6-inch aircraft design space, which was largely unknown at the time. About twenty balsa wood gliders with different wing configurations were built, and simple tests were performed to determine the lift-to-drag ratios. These tests showed that the disc configuration had some promise, so a powered version was built next. The powered 6-inch disc performed a 9-second flight in the spring of 1996. The endurance was gradually increased using the disc configuration, culminating in a 16-minute flight using lithium batteries in November of 1997. This MAV weighed 40 grams, it was manually controlled by elevons, and it did not carry a payload (Figure 1). Figure 1: Early MAV prototype American Institute of Aeronautics and Astronautics 2 Multidisciplinary Design Optimization The early prototypes demonstrated that a 6-inch aircraft was feasible. However, the MAV still required a video camera and an advanced control system that would allow operation by an unskilled operator. Since the prototype MAVs were clearly not capable of handling the extra weight and power of these additional systems, a more rigorous design approach was required to continue evolving the system toward maturity. For this reason, a Multidisciplinary Design Optimization (MDO) methodology was developed in the summer of 1998 to maximize the performance of the MAVs. The goal of the MDO methodology was to create a computer-simulated environment in which the optimum MAV configuration could evolve. The simulated environment consists of physics-based models of the key aspects of the MAV design space, as shown in Table 1. The design variables used for the www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：Development of the Black Widow Micro Air Vehicle
