The Development Of 6-DOF Tank Driving Simulator

With the development of military science and technology, supported by computer simulation, the virtual reality simulated training becomes more important, in order to reduce personnel, goods and materials of actual fight lose and economize training funds. The training way to drive and fighting with the tank driving simulator based on virtual reality to the driver, has advantages of energy-conservation, security, economy, is not restricted by time, climate, place while training, and may make the train high-efficient, short train cycle. It improves the result of training greatly, and exercise army very well among the environment of virtual reality, will become tank drive the development trend trained. Virtual reality technology merged such a lot of information technology branches as digital graphics process, computer graphics, multimedia technology, sensor technology, and it is a rising information technology at the end of the 20th century. The development of virtual reality technology in our country has just started, but it is several years that researching the driving simulator. It is no problem that realization of various kinds of sport scenes and vision simulation, but the sense of drive immersing it is not strong, so the training is not very efficient. Battlefield is complicated and changeable, it need simulate six degree of freedom at the sport its and combine real-time vision simulation to reproduce environment of driving. In this paper, tank driving simulator is developed, combining the six degree of freedom parallel robot based on virtual reality, it may create for driver a very true three-dimensional battlefield environment, and support real-time sensation of approaching real driving movement, can make it preliminary simulated that driving state in the course of tank running and fighting. As Fig. 1 shows, driving simulator include drive operating system, top management computer, visual simulation system and movement system, etc. Drive operating system is operated by driver, and the drive intention is offered to top management computer; Visual simulation deals with operation messages through various kinds of dynamics models of driving, receives the kinematics parameter, carry on the visual simulation, and reflect in real time through the large screen display and stereo system; Meanwhile, visual system sends the datum of imitated movement to the driving movement simulation control system for controlling simulation posture through distributed controllers; Distributed controllers gather data of movement platform in real time, then give feedback to top management computer through movement simulation system, top management computer through the close ring carries on accurate control to movement simulation system, and makes the movement platform produce the lifelike driving simulation result. In this way, the driver gets much experience, such as vision, hearing, touch, etc., just like driving really. As Fig. 2 shows, there is the systemic composing of 6-DOF movement simulation. Through providing the 6-DOF parallel robot kinematics model, setting up kinematics negative solution and the transfer-function of system, and setting up the control software of the movement simulation system with virtual device(VxD) under Windows 98 system, it is realized that the real-time control to the servo system of the electric-liquid. Sense of reality for figure to draw is one important component in the tank driving simulator; the figure can't reflect the "virtual reality", unless there is sense of reality. It is necessary to creating tank driving visual simulation system, that the state of the operation system, for example the state of throttle, the shelf location, the state of the clutch, the state of the brake, the change shelf to operate, the veer operate etc., the topographical data offered in the visual system, and the real-time calculation of the dynamics model for offering such driving information as the speed, direction of the tank, etc. Meanwhile, the visual offer the necessary data for the instrument shows in real time, for example: speed, the rotational speed of the Fig. 2 Composing of 6-DOF Parallel RobotFeedback Module Servo ValveHydraulic Pressure SystemControl ComputerServo Control ModuleExecutive Moduleengine. Through setting up the tank running dynamics model sharply, and the tank veer dynamics model, including veers at both the horizontal and the slope, and discussing the stability of the tank, the tank virtual drive simulation model can be created to apply to the visual simulation system. Under Windows 2000 operating system, based on the tank virtual drive simulation model, the visual software of tank driving simulator is developed. The high fidelity, high specialization, the best real-time three-dimensional modeling tool, Multigen Creator; the three-dimensional figure programming language OpenGL that independent of operating system and transplanted ability in the platform well; the management software of the scene based on OpenGL, OpenGVS; and the Microsoft Visual C++ 6.0 target-oriented programming technology are used in the visual system. In the course of creating model, proceeding from the whole system optimization, the system adopts the real-time graph processing algorithms used much by CIG system at present. Disappear and latent use BSP cut apart technology; increasing sense of reality uses MIP technology and Gouraud light-shade technology, dealing with the complicated object model for reduce hardware consumption of polygon uses LODs technology. The difficult points in the visual simulation, including collision detection and following terrain, are solved. The communication link between visual simulation system and movement simulation system adopts User Data Protocol(UDP), and it can change date real-timely. The visual system of 6 DOF tank driving simulator, using the PC of Windows 2000 operating system, Pentium 2.66GHz, memory 512MB, display card GeForce4 MX440, can realize tank all kinds of operation, such as start, accelerate, brake, veer, firing, and realize following terrain, collision detection, adjusting gun turret and barrel, hitting goal etc. The visual system depends on reading and judging the information of operating to control tank state, so it has better vision immerse sense. Meanwhile, through the real-time communication between visual system and movement simulation system, the gesture of movement platform is controlled by the real-time information that the visual system supports to simulation of control system. So vision, sense of touch and body sense are unified, and the problem, that interaction and immerse sense of driving simulator are not very well, is solved. Through the experiment examining, the tank driving simulator can follow real-timely the movement of the tank model in the visual system, and get the effect while tank starts accelerates, brakes, veers and fires. Driver can experience various kinds of body senses that the real tank drives when he sits in the seat of the tank driving simulator. can reach the demand of drive training. Because of the limitations of time and condition, the tank driving simulator...