The simulation of aerial flying targets is widely needed in many fields. This paper proposes a physically based method for optical simulation of flying targets. In the first step, three-dimensional target models are built and the motion speed and direction are defined. Next, the material of the outward appearance of a target is also simulated. Then the illumination conditions are defined. After all definitions are given, all settings are encoded in a description file. Finally, simulated results are generated by Monte Carlo ray tracing in a physically based renderer. Experiments show that this method is able to simulate materials, lighting and motion blur for flying targets, and it can generate convincing and highquality simulation results.
When using numerical simulation method study laser system, modeling and simulation energy distribution of the target echo on the detector is studied in order to achieve closed-loop optical path. From the perspective of Fresnel formula, using bidirectional reflectance distribution function (BRDF) model to calculate the intensity distribution of the target reflection; calculation of light vector angle expression reflects the phase change between reflected light and incident light when light travelling in a single medium surface. Setting position parameters and attitude parameters of different components in the laser simulation system, through the calculation of geometric relationship, the energy distribution under the view of the detector is achieved. Target surface shape was respectively set for planar, spherical and cylindrical. Analyzed the influence of targets surface roughness root mean square (RMS), zenith angle and azimuth angle of the incident light to targets reflection characteristics respectively. Results show that this method can accurately achieve the detection simulation of simple geometric shape surface target in laser system.