Research Of Fill Light And Low Speed Characteristic Based On The Infrared Dome Camera

Infrared Dome Camera is set integrated camera, PTZ transmis sion, lighting system, decoders and other components in one of the surveillance products, as an important part of the video surveillance system, it has played in all types of video surveillance applications in an increasingly important role. Based on the actual engineering application background, in view of the video monitoring field of dome camera’s night vision function is not perfect, athletic performance is not ideal, mainly studies the fill light system and low speed characteristic of Infrared Dome Camera. Specific work as follows:(1) C hoose the dot- matrix infrared leds based on the technology of IR- III as the fill light system light source. Designed infrared lighting system hardware drive scheme through using an STM32 as PWM generator and PT4115 as infrared lamp dimming chip. Compared to the traditional dc voltage dimmer, this scheme ensures the fill light lamp brightness at the same time doesn’t change the shade of the lamp.(2)According to the principle of lens imaging and Weber – Fechnet law, a kind of fill light system control algorithm based on infrared lamp brightness and lens ratio matching was innovatively put forward, designed software control scheme based on the SONY VISCA protocol, The experimental results show that the control algorithm is very good solve the problem, such as serious heating of infrared dome camera lighting system, center overexposure when to collect images closely.(3)From the theoretical analysis of the factors that affect the infrared dome camera’s low speed characteristic. Analyzes the four kinds of static friction model, the dynamic Lu Gre friction model and the mathematical model of stepper motor, Based on Simulink simulation verified the friction torque and motor torque ripple effects on infrared dome camera’s cradle head low speed movement. And from the perspective of improving the motor torque ripple, through the study of stepper motor and driver chip selection, designed a kind of stepping motor based on TMC5031 hardware driver program. The experimental results show that the motor output torque under the control of this scheme has no obvious fluctuation, and dome camera low speed running smooth.(4) Designed the PC control software based on the Lab VIEW, studied lens and cradle head communication control protocol Based on PELCO-D, finally based on the control scheme of the chapters mentioned before building the experiment platform.