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

1249
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

  • Analysis of Optically Pumped Semiconductor Laser Technology for Promoting the Development of Life Sciences

    Optically Pumped Semiconductor Lasers technology has achieved great success in the market due to its various unique advantages, with over 100000 OPSL devices currently operating in the market. This article introduces the application and new developments of OPSL in the fields of flow cytometry and DNA sequencing.OPSL has the characteristics of flexible wavelength extension, adjustable power, compac...

    2024-02-01
    See translation

  • Teledyne Technologies acquires a portion of its optoelectronic business

    Recently, Teledyne Technologies announced that it has reached an agreement to acquire a portion of Excelitas Technologies' aerospace and defense electronics business for $710 million in cash.This acquisition includes the optical systems business under the Qioptiq brand headquartered in North Wales, UK, as well as the Advanced Electronic Systems (AES) business headquartered in the United States.It ...

    2024-11-12
    See translation

  • Veeco Instruments wins IBM big order

    On August 14th local time, Veeco Instruments, a well-known American laser annealing manufacturer, announced an important cooperation with technology giant IBM. It is reported that IBM has selected Veeco Instruments' WaferStorm wet processing system as support for its advanced packaging applications, and the two parties have signed a joint development agreement to explore the potential of utilizi...

    2024-08-23
    See translation

  • Aalyria plans to establish a laser link mesh network to quickly transmit data on land, in the air, in the ocean, and in space

    Aalyria is establishing a laser link mesh network to quickly transmit data on land, in the air, in the ocean, and in space. The maritime part of the plan is about to be pushed forward.Recently, this DC based laser communication network company announced the signing of a memorandum of understanding with HICO Investment Group, which focuses on investing in shipping and logistics companies. According...

    2023-10-26
    See translation

  • BLT launches a new BLT-S800 metal PBF 3D printer equipped with 20 lasers

    Bright Laser Technologies (BLT), a global leader in additive manufacturing headquartered in China, has launched a new BLT-S800 metal 3D printer with a super large construction volume (800 mm x 800 mm x 600 mm) and a 20 fiber laser configuration, which can shorten part delivery time and achieve rapid customer manufacturing.The BLT-S800 system supports titanium alloy, aluminum alloy, high-temperatur...

    2023-10-19
    See translation