35results about How to "Guaranteed ranging accuracy" patented technology

The invention belongs to the technical field of intelligent transportation and relates to a front vehicle ranging method based on monocular vision. The method includes: adjusting the posture of a vehicular camera, considering the pitch angle variation range due to bumping to adjust the pitch angle of the camera, and using the obtained actual measurement data to segmentally fit the functional relation between an ordinate and an actual longitudinal distance at different pitch angles and the functional relation between the ordinate and an actual transverse distance represented by per horizontal pixel at different pitch angles; and when a vehicle runs, calibrating real-time pitch angle of the camera according to left and right lane lines detected in real time and a three-line calibration method, and then using the linear interpolation method to calculate to obtain the distance between the vehicle and a target vehicle. The front vehicle ranging method based on monocular vision has a real-time dynamic compensation effect on ranging error caused by vehicle bumping and can be used for accurately calculating the distance between the vehicle and the front vehicle.

The invention discloses an AGV positioning navigation system and method based on RFID and ultrasonic waves. The system is characterized by comprising n vehicle-mounted terminals and a monitoring service center, the n vehicle-mounted terminals are used for finishing a plurality of distribution tasks in the indoor work environment, and any vehicle-mounted terminal comprises a vehicle-mounted Wi-Fi communication module, an RFID and ultrasonic positioning module and a control module. The monitoring service center comprises a Wi-Fi communication module, a route management module, a GIS search engine and a database. A layout graph of the indoor work environment is saved in the database. The synchronization problem caused when emitting and receiving of ultrasonic waves are not on the same side is solved on the system level by means of the positioning technology combining RFID and ultrasonic waves. Positioning precision of an AGV is improved by means of the positioning algorithm of a least squares support vector machine.

The invention discloses a ranging system for high-precision on-line measurement, comprising: a laser generating unit (1), a transceiver optical antenna unit (2), a ranging signal receiving and processing unit (3), a frequency stabilizing unit (4), a main Control unit (5), secondary power supply unit (6) and host computer unit (7). In the present invention, a dual-comb femtosecond laser and a fiber laser are used as the light sources of the system's laser precision measurement and laser rough measurement and ranging, respectively, and based on the femtosecond dual-comb nonlinear down-sampling principle to realize non-contact high-precision online measurement, with With the advantages of high precision, high frequency response, low power consumption, and small size, it is very suitable for measuring large-scale satellite antenna deployment mechanisms and key components of large aircrafts, and realizing on-orbit deployment and on-orbit splicing of large-scale antenna observation satellites.

The invention discloses an emergency rescue personnel location system and an emergency rescue personnel location method. The emergency rescue personnel location system comprises a position presenting subsystem, a data receiving-transmitting subsystem, a temporary location station subsystem and a personal location subsystem, wherein the temporary location station subsystem comprises a plurality of temporary location stations; the personal location subsystem comprises a plurality of personal location modules, the data receiving-transmitting subsystem is respectively connected with the position presenting subsystem and the temporary location stations, and the temporary location stations are connected with the personal location modules. The ranging distance in an open space can reach 1km, and the ranging precision is less than or equal to 3cm under 99% situation. The emergency rescue personnel location system can effectively penetrate through a load-bearing wall with the thickness of 30cm inside a room; even in a large-sized building, the effective transmission of the data also can be guaranteed. Under the outdoor situation, the transmission distance in the open space can reach 2 km, the transmission distance is more than 300m when an obstacle exists, and in order to guarantee sufficient diffraction performance, on the aspect of the wireless data transmission, a Mesh network working at 433Mhz is adopted.

The invention provides a distance measuring data processing method under an incoherent measuring system. By the method, cycle skipping in distance measuring of the incoherent measuring and control system, and distance measuring precision of the system is guaranteed. According to the technical scheme, the method includes: in an FPGA (field programmable gate array) circuit of a responder, using digital circuits to perform capture tracking, carrier synchronization tracking, data demodulation, bit synchronization and frame synchronization to uplink pseudo codes; extracting frame count value from uplink demodulated data; using a pseudo code clock counting method to convert chip counting into bit counting, code cycle counting and code counting through simple mathematic conversion, using a double code clock sampling method with a phase difference of 180 degrees to perform sampling and time difference comparison to code counting and code phase sampling, distinguishing distance skipping value for algorithm correction, eliminating distance cycle skipping corresponding to code counting, filling pseudo distance information of the acquired uplink pseudo codes into downlink measuring frames in real time, and sending back to a ground measuring and control station to cooperatively complete incoherent distance measuring.

The invention relates to a sequence component relation based range finding method for a single-end fault of a power transmission line. A replay protector is used to determine a fault type, the sequence component relation in positive, negative and zero-sequence network is determined according to the fault type, sequence electrical quantities at the measuring end are used to calculate sequence electric quantities at the fault point, and the sequence electric quantities of the fault point are substituted into the sequence component relation to solve a fault distance. The method can be used to overcome the problems that data is asynchronous and false root exists, and maintains high range finding precision.

The invention discloses a temperature control system for controlling optical fiber temperature excursion and a control method of the temperature control system. An aluminum alloy cylinder is placed in the middle of a glass fiber reinforced plastic cubic box, and a gap between the aluminum alloy cylinder and the glass fiber reinforced plastic cube is filled by aerogel. Deionized water is fully filled inside the aluminum alloy cylinder, an optical fiber winder is submerged by the deionized water, and a sealing ring is added between the aluminum alloy cylinder and a cylinder cover for sealing. The outer surface of the whole cylinder is plated with silver coatings. A plurality of layers of heat insulation materials covers the outer wall of the glass fiber reinforced plastic cubic box of the whole device. The low heat conducting performance of the multilayer, the aerogel and the glass fiber reinforced plastics is utilized, and the influence on the inside optical fiber caused by external heat sources is prevented. Through the deionized water with great specific heat capacity and aluminum alloy liquid with good heat conducting performance adopted at the inside, the heating quantity generated by the optical fiber per se is diffused as soon as possible, and in addition, the caused temperature is diffused as little as possible. The temperature control system has the advantages that the temperature excursion of the optical fiber is effectively controlled, and distance measuring signals transmitted to the tail end of the optical fiber are enabled not to generate the distortion phenomenon.

The invention discloses a working state management method and system for a digital car key. The digital car key includes an electronic device with a digital key system, and a low-precision wireless communication system and a high-precision wireless communication system are arranged in the digital key system; the method It includes the first management method for the electronic equipment from the standby state outside the car to entering the vehicle: when the electronic equipment is in a stationary state, the wireless broadcasting of the digital key system is turned off; when the motion state of the electronic equipment reaches a preset condition, then Turn on the wireless broadcast; when the electronic device is close to the car end and the distance from the car end reaches the preset value, turn on the high-precision wireless communication system; when the electronic device enters the car, prolong the connection interval of the digital key system; through the above method, respectively The power consumption of the digital key system is optimized in several stages, such as standby outside the car, connection maintenance, dynamic ranging, and standby in the car, so as to improve its utilization efficiency of power and prolong the standby time.