Español

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

246
2023-08-23 14:12:19
Ver traducción
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
Recomendaciones relacionadas
  • Natural Communication: Oxide Dispersion Enhancement for High Performance 3D Printing of Pure Copper

    The laser additive manufacturing technology of pure copper (Cu) with complex geometric shapes has opened up vast opportunities for the development of microelectronic and telecommunications functional devices. However, laser forming of high-density pure copper remains a challenge.Recently, the forefront of additive manufacturing technology has noticed a joint report by the University of Hong Kong, ...

    04-11
    Ver traducción
  • Tailoring 'hollow' hydrogen molecule generation with two-color, bicircularly polarized laser pulses

    Rydberg atoms and molecules are characterized by having one or more electrons in highly excited bound states. Such atoms and molecules are said to be in “Rydberg states” and are also called “hollow” atoms and molecules. Rydberg states are useful for studying various phenomena arising in intense light–matter interaction that involve electronic excitation with an intens...

    2023-09-16
    Ver traducción
  • 20 million dollars! Undersea fiber optic agreement reached, fully operational by 2026

    Recently, Confluence Networks LLC has announced a long-term partnership agreement with Laser Light Communications Inc., a developer and provider of software controlled optical network services.According to the agreement, Laser Light will adopt Confluence-1 submarine fiber optic network, which Confluence Networks is about to launch, as the core part of its global network. The protocol will last for...

    2024-05-24
    Ver traducción
  • 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
    Ver traducción
  • Reshaping the Sky: Laser Scanning Drones Innovate Data Collection

    Imagine soaring above the Earth, the world unfolds in patterns and reliefs, and the terrain whispers its secrets in the wind. Now imagine capturing these whispers and translating them into a digital language to draw our world map with unprecedented accuracy. Welcome to the forefront of laser scanning drones, a technological ballet in the sky where the fusion of flight and laser precision is reshap...

    2024-04-07
    Ver traducción