The Study And Development Of Computational Simulation Software On The Photometric Characteristic Of Lamps Reflectors For Vehicles

The development trend of the headlamp is distributing light with the reflector which is difficult to design, so its design must take advantage of the CAD technique and is guided by the computational simulation software.Firstly, the calculation methods of lighting optics, such as ray tracing method, Monte Carlo method and flux transmission method, are discussed, Further more the characteristic and the application field are anatomized and compared, consequently the flux transmission method is selected as the main method of computational simulation software of photometric characteristic of headlamps for vehicle. Then its numeric value calculation method is deducted.Secondly, the software definition, software overall design and detail design including the selection of the development mode and the development tool, the flow chart of the simulation software of illumination, the computational simulation models of illumination of the headlamp bulb, the reflector and the measure screen, the process of simulation result and the calculation efficiency, and so on, are presented in this paper.Thirdly, a computational simulation software of the photometric characteristics of headlamp for motor vehicles was developed with Visual C++ on the CAD platform of UG. according to the design scheme of the simulation software of illumination.Finally, the reliability of computational simulation software is analyzed. After the comparing the simulation results with the theoretic results under the three followed condition: a point light source on the parabola reflector focus, a point light on the ellipsoid reflector focus and a point light source before the parabola reflector focus, a conclusion is gotten that the two results are generally accordant, the accuracy of the simulation software reach the engineering requirements and the computational simulation software of photometric characteristics of headlamp of motor vehicles can guide the design of the headlamp reflectors. At the end of this paper, the reasons of error are discussed and the methods to reduce the error are given.