chanelink logo
CHANELINK
English

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

1327
2023-08-23 14:12:19
See translation
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
Related Recommendations

  • Breakthrough! Extending the lifespan of solar panels to 50 years using lasers

    Recently, the National Renewable Energy Laboratory (NREL) under the US Department of Energy has made a revolutionary breakthrough by developing a concept validation method aimed at completely removing polymers from solar panel manufacturing, thereby achieving more efficient and environmentally friendly recycling.Solar panels have always been praised for their recyclability. However, the thin plast...

    2024-04-30
    See translation

  • Trumpf 3D printing technology innovation: zero support structure, low waste, unlimited possibilities

    Ditzingen, Germany, September 8, 2023) - TRUMPF, the world's leading provider of machine tools and laser technology solutions, has improved its 3D printing software TruTops Print to print parts with suspension angles as low as 15 degrees with little need for support structures. Trumpf will present its new technology at the European International Machine Tool Show (EMO 2023) in Hannover, Germany.Fi...

    2023-09-13
    See translation

  • Tianjin University's Photoacoustic Remote Sensing Microscopy Technology Breakthrough New Heights

    Recently, Professor Tian Zhen's team from Tianjin University has made a breakthrough in the field of photoacoustic remote sensing microscopy technology and successfully developed a new type of non-destructive testing method. This technology uses Kaplin high-power femtosecond laser as the key light source, further optimizing the solution to the internal flaw detection limitations of inverted chips,...

    2024-04-16
    See translation

  • Netherlands Integrated Photonics Ecological Platform Raises € 60 million to Support European Photonics Startups

    PhotonVentures, based in Eindhoven, the Netherlands, has announced the launch of a venture capital fund designed to help early-stage photonic chip startups and scale-up businesses.In the first round of funding, PhotonDelta, a Dutch photonic integrated circuit (PIC) pioneer, raised €60 million as the lead investor and numerous private investors. PhotonVentures said it plans to raise a total of...

    2023-09-02
    See translation

  • Tsinghua University makes progress in the field of pre sensing optical computing

    In the era of the Internet of Things, visual image sensors, as key devices in the intelligent society, are embedded in various devices such as mobile communication terminals, smart wearable devices, automobiles, and industrial machines. With the continuous expansion of applications, higher requirements have been put forward for the system power consumption, response speed, safety performance, and ...

    2024-08-05
    See translation