chanelink logo
CHANELINK
Türkçe

The visual LiDAR fusion calibration board improves the detection accuracy of the vehicle navigation system and does not need to be adjusted before sailing

428
2023-08-23 14:12:19
Çeviriyi gör
At present, the navigation system has become an important equipment on ships, aircraft, missiles, automobiles and other navigational vehicles. Laser Doppler radar has become an important development direction in the field of velocity measurement technology because of its high accuracy, good spatial resolution and fast dynamic response.
 
The application of the three-beam Doppler Lidar in the vehicle navigation system can continuously measure the navigation parameters of the vehicle relative to the ground, such as three-dimensional axial speed and instantaneous position, and realize the autonomous navigation, and it does not need to be adjusted before sailing, and it is simple and convenient to use.

With the continuous improvement of the detection performance of multi-beam radar such as SNR and velocity sensitivity in engineering applications, more in-depth research on beam configuration is needed. The vehicle-mounted three-beam Doppler Lidar beam is illuminated by a combined transceiver antenna. Whether direct detection or coherent detection is used, it is desirable to obtain a large echo signal intensity.
 
However, in the actual measurement process, the intensity of the echo signal is greatly attenuated because of light scattering on the rough surface. The bidirectional reflection distribution function (BRDF) of a rough surface can describe not only the optical radiation properties of the surface, but also the directional scattering properties.

Three beam Doppler Lidar uses continuous wave laser for optical mixing (homodyne detection) measurement. After the signal light transmitted by liDAR in the atmosphere, the echo signal and the local oscillator signal of the system generate the difference frequency signal through the optical mixer. When the local oscillator frequency is equal to the emitted laser frequency, the difference frequency is the Doppler shift of the echo signal.

When the three-beam laser illuminates the ground at an oblique Angle, the different beam illumination Angle will cause the different working distance of the beam, which will affect the signal-to-noise ratio of the system. If the installation height of the three-beam antenna is H, the working distance of the beam is R=H/sinα. The SNR of the system monotonically increases with the increase of the remaining zenith Angle. When the signal-to-noise ratio of coherent laser radar is higher than 8dB, the estimated maximum likelihood reaches the Kramerlau lower bound (CRLB).

When the system hardware parameters and algorithms are selected, the sensitivity of velocity measurement is only related to the zenith Angle and decreases with the increase of the zenith Angle. Speed measurement sensitivity can not be too small, otherwise the instrument will fail to respond to the operating speed, usually need to give the practical application of speed measurement sensitivity or can be converted to the index requirements.

Hangxin photoelectric laser radar calibration plate has good stability and can obtain repeated accurate data. Suitable for automatic driving distance, identification testing and remote sensing targets and other fields, the reflectivity is 1-99% optional, does not drop powder and does not change yellow, with nearly perfect Lambert characteristics. Hangxin photoelectric diffuse reflector adopts exclusive spraying process, which can provide a variety of reflectivity splicing diffuse reflector for seamless splicing.

Source: Sohu
İlgili öneriler

  • Laser Photonics officially launches its SaberTech laser cutting system

    Recently, Laser Photonics (LPC) officially launched its SaberTech laser cutting system. This system not only enriches the product line of LPC's laser cleaning, welding, marking, and engraving systems, but also marks another important breakthrough for the company in the field of laser technology. This product release is another heavyweight measure after LPC's latest generation laser cleaning system...

    2024-06-19
    Çeviriyi gör

  • The research team at the University of Electronic Science and Technology of China has developed three innovative photonic devices

    Recently, Professor Nie Mingming from the Key Laboratory of Fiber Optic Sensing and Communication at the School of Information and Communication Engineering, University of Electronic Science and Technology of China, in collaboration with the University of Colorado Boulder, published a research paper titled "Cross polarized stimulated Brillouin scattering empowered photonics" in the top internation...

    05-30
    Çeviriyi gör

  • Micro devices output powerful lasers at room temperature, reducing power consumption by 7 times

    Recently, researchers at the Rensselaer Polytechnic Institute in the United States have invented a miniature device thinner than human hair, which can help scientists explore the essence of light and matter and unravel the mysteries of the quantum field. The most important advantage of this technology is that it can work at room temperature without the need for complex infrastructure. The resea...

    2024-05-29
    Çeviriyi gör

  • The green and blue laser diode series provides higher beam quality

    Rutronik has expanded its optoelectronic product portfolio by introducing green and blue laser diodes packaged in metal cans TO38 and TO56 using AM OSRAM. They leave a deep impression with improved beam quality and stricter electro-optic tolerances. The power level of the laser diode ranges from 10mW to 100mW. Diodes such as PLT3 520FB and PLT5 450GB are now available on the market.The flexibility...

    2024-01-31
    Çeviriyi gör

  • Abnormal relativistic emission generated by strong interaction between laser and plasma reflector

    The interaction between strong laser pulses and plasma mirrors has been a focus of recent physical research, as they generate interesting effects. Experiments have shown that these interactions can generate a nonlinear physical process called high-order harmonics, characterized by emitting extreme ultraviolet radiation and brief flashes of laser light.Researchers from the Czech Extreme Light Infra...

    2023-12-04
    Çeviriyi gör