31 results about "Laser doppler velocimeter" patented technology

A motion member (1) urged by an application spring (4) is made to collide with a surface of a sheet material supported by a support member (14) so as to be deflectable and deformable. The velocity of the motion member (1) during the collision process is detected every second by a measuring portion (17) of a laser Doppler velocimeter. A control circuit (121) measures the velocity of the motion member (1) immediately before the collision of the motion member (1) with the sheet material, the time period of deflection deformation until the sheet material collides with an opposing member (15), and the time period of compression deformation after the collision of the sheet material with the opposing member (15), and outputs a result thereof as sheet material information to a control portion (120). The timing at which the sheet material collides with the opposing member (15) is detected by an output of a piezoelectric element (16) connected to the opposing member (15).

A double-optical path laser Doppler velocimeter includes a laser source, a light source beam splitter, a photoelectric receive and electronic process system and a focusing system, among which, the laser source, the beam splitter, the photoelectric receive and electronic process display system, a mobile lens and a fixed lens in the focusing system are set on the optical axis of the propagating direction of the laser source beam orderly from left to right to compose a measurement system. The moving direction of the object and the axis of the test system are vertical to the optical axis of the laser ranger, a step motor controller drives the step motor to drive the ballscrew based on the distance of the tested moving object to regulate the distance between the mobile and the fixed lenses to let the laser beam focus drop on the tested moving object accurately.

The invention discloses a LDV / INS (Laser Doppler Velocimeter / Inertial Navigation System) combination-based vehicle-mounted height measurer and a method thereof. The vehicle-mounted height measurer comprises an inertial navigation system, a laser Doppler velocimeter, a signal solving unit and a height information display unit, wherein the inertial navigation system and the laser Doppler velocimeterare arranged on a vehicle; the inertial navigation system is used for measuring a real-time pitch angle of the vehicle in the driving process and transmitting the measured real-time pitch angle information to the signal solving unit; the laser Doppler velocimeter is used for measuring a real-time speed in the vehicle driving process and transmitting the measured real-time speed information to thesignal solving unit; the signal solving unit is used for solving to obtain an elevation height increment of the vehicle in a set unit time interval according to the speed information and the pitch angle information, accumulating all height increments from an initial point to a to-be-measured point, and finally solving the elevation of the to-be-measured point. The vehicle-mounted height measurerdisclosed by the invention has the characteristics of being capable of avoiding influence of meteorological changes, small in influence of atmospheric refraction, high in working efficiency, high in measurement accuracy and the like.

The invention discloses a tight combination method for calculating a pseudo range / pseudo range rate by using a Doppler velocimeter. The method comprises: step 1, installing a strapdown inertial navigation system, a laser Doppler velocimeter, and a Beidou satellite navigation system at a moving carrier, and electrifying the combined navigation system for starting up; step two, carrying out initial position parameter binding; step three, keeping the moving carrier to be still for five minutes, carrying out initial alignment to obtain an initial attitude angle; step four, starting a tight combination mode and starting the moving carrier; and step five, carrying out calculation to obtain a pseudo range value and a pseudo range rate value, and carrying out tight combination navigation by using differences between the pseudo range value and pseudo range rate value and pseudo range and pseudo range rate values outputted by a Beidou satellite navigation system as observation values of the combined navigation system. According to the invention, tight combination with the Beidou satellite navigation system is carried out by using the pseudo range value and pseudo range rate value calcualtd by the laser Doppler velocimeter and function complementation is realized; and the pseudo range value and pseudo range rate value of the moving carrier are deduced based on the location of the moving carrier and the Beidou satellite, so that high-precision navigation is realized.

The invention discloses a particle velocity measurement system of the impact surface and the free surface of a light-transmitting material, which includes a launch device, an impact object, a target plate, a target frame, and an all-fiber laser Doppler velocimeter, and the impact object is controlled by the launch device. The target plate is made of light-transmitting material, the impact surface of the target plate is coated with a total reflection film, the free surface of the target plate is coated with a semi-reflective film, the target plate is fixed on the target frame, and is facing the impact object, so The laser lens of the all-fiber laser Doppler velocimeter is directly arranged on the side of the target plate coated with a semi-reflective film, and is at a certain distance from the semi-reflective film. connected to the main body of the instrument. The invention solves the problem that the existing flat plate impact experiment device cannot accurately measure the particle velocity of the free surface of the target plate, and cannot simultaneously measure the particle velocity of the impact surface of the target plate, and has the advantages of accurate measurement results, high precision, and less susceptible to environmental interference The advantages.