429results about How to "Little impact on accuracy" patented technology

The invention discloses a monocular and IMU fused stable motion tracking method and device based on a mobile terminal, belonging to the technical field of AR/VR motion tracking. The method comprises the following steps of: judging whether the number of tracking feature points of a current frame of an image is greater than a pre-set threshold value or not, if so, performing feature point tracking by adopting an optical flow method so as to obtain the current pose of a camera, if not, obtaining feature points by adopting a FAST feature detection operator, and performing feature matching of the image by adopting a BRIEF algorithm calculation descriptor so as to obtain the current pose of the camera; performing Kalman filtering of the current pose of the camera so as to obtain a visual pose; obtaining acceleration and angular speed values generated by an IMU in a three-dimensional space, and performing integral operation of the acceleration and angular speed values so as to obtain the pose of the IMU; and performing Kalman fusion of the visual pose and the pose of the IMU, and performing motion tracking. Compared with the prior art, more stable and rapid motion tracking can be obtained on mobile terminal equipment.

The invention relates to an automatic generating method for a multi-lane vehicle track space-time diagram. The method comprises the steps that firstly, a camera is utilized for obtaining internal parameters and external parameters of the camera through off-line calibration, an area of interest is set according to the actual monitoring requirement, and three virtual detecting belts are set at the upstream initial position of the traffic flow; secondly, the vehicle feature points are extracted based on the three virtual detecting belts, the feature point tracking and grouping correction are carried out according to vehicle grouping, the vehicle tracks are extracted in a high-precision mode, a longitudinal space-time track diagram of passing vehicles is automatically generated for each lane, and a transverse space-time track diagram comprising all lanes is generated; finally, whether it is in the lane line correction stage or not is automatically judged, wherein if yes, the lane line position is automatically corrected based on the track clustering method. Compared with the prior art, the method improves the robustness of the target luminance change, improves the precision of vehicle detecting and track tracing, is capable of well automatically correcting the lane line on line and avoids misjudgment on the lane number to which the vehicle track point belongs.

The invention discloses a tunnel construction informatization dynamic monitoring system and a monitoring method thereof. The system comprises an industrial personal computer, a PLC (programmable logic controller) wireless controller, a high-configuration digital camera, a deformation monitoring sensitization part, digital display acquisition equipment, wireless transmission equipment and a dynamic design feedback device. The method includes: 1), controlling commands to be transmitted to the PLC wireless controller by a computer control main station and controlling the digital camera and the digital display acquisition equipment; 2), acquiring internal force monitoring data by the aid of the digital display acquisition equipment; and acquiring a deformation monitoring image via the deformation monitoring sensitization part by the digital camera; 3), transmitting a monitored value to the computer control main station by the aid of the wireless transmission equipment; 4), analyzing results by the computer control main station via a real-time analysis module; and 5), transmitting the analyzed results to the dynamic design feedback device, analyzing relative difference of the really monitored value and a standard value, and early warming in real time by an early warning module. The tunnel construction informatization dynamic monitoring system is scientific, safe and practical, the method is convenient, instant, fast and effective, and safety problems in construction monitoring of tunnels are avoided.

The invention provides a real-time object three-dimensional reconstruction method based on a depth camera. The method comprises the steps that a frame pf depth image is sequentially acquired from thedepth camera as a current frame and is preprocessed; the relative pose of the current frame and the previous frame is estimated through a centroid ICP algorithm, and the precise pose of the camera ofthe current frame is calculated by using the precise pose of the previous frame and the relative pose of the current frame and the previous frame; the current frame data are fused into the local TSDFby using the precise pose of the camera; and point cloud integrated into the local TSDF in the step 3 is acquired from the local TSDF, and the point cloud is used as the point cloud of the previous frame, or match fusion is carried out on the local TSDF and the global TSDF, and the local TSDF is initialized. According to the invention, the failure of the ICP matching algorithm is avoided; accumulated errors are reduced; the accuracy of a model is improved; and the method is suitable for reconstructing a specified object or person.

The invention discloses a double-shaft photoelectric rotary table compound control system and a control method based on fuzzy decision. The control system comprises an integrated digital filtering, an estimation unit, a feed-forward control unit, a measuring unit, a change-over switch, a fuzzy-decision unit, a piping and instrument diagram (PID) controller, and a signal superposition unit. The double-shaft photoelectric rotary table position error e is compared with an error threshold K c set in advance, when e is less than K c, the fussy regulation is entered and regulation output controlled quantities delta kp, delta k and delta kd are obtained. PID control and regulation parameters kp, ki and kd are further obtained, and PID calculation is conducted. Otherwise, PID calculation is conducted by the utilization of the fixed regulation parameter set in advance and control signals outputted by PID are obtained. The effects of nonlinearity, time-varying characteristics, and model uncertainty on accuracy of the double-shaft photoelectric rotary table are effectively reduced. The problems of integral saturation and high frequency disturbance in the PID controller are solved, stochastic noise in the given stochastic signals is overcome, and long-term continuous stable work of the double-shaft photoelectric rotary table compound control system is ensured.

The invention, which belongs to the combined navigation technology field, discloses an accelerometer calibration method based on GPS velocity information. The method comprises the following steps: step 1, collecting measurement data of a GPS measurement system and a DR measurement system; step 2, determining usability of the GPS measurement data; step three, employing a least square method to estimate a scale factor and a zero offset error of an accelerometer; step four, comparing estimation values of the scale factor and the zero offset error of the accelerometer with estimation values of a preset accelerometer scale factor and a preset accelerometer zero offset error to determine whether updating is carried out; and step five, meeting a time interval requirement and then returning to the step two to carry out next calibration. According to the invention, a GPS characteristic that the GPS enables a measurement value precision to be high at a linear motion segment with good signal reception and high speed is utilized to realize dynamic calibration on an accelerometer, so that calibration parameter of the accelerometer can be updated regularly and an influence on the system precision by a zero offset change caused by different starting and temperature changes can be reduced. Moreover, the realization is simple, the calculation amount is small, and the result is reliable.

The invention relates to a deep space detector astronomy/radio combination navigation method based on ephemeris correction. The method comprises the following steps: establishing a Mars detector state model and astronomy astronomy navigation and radio navigation subsystem measurement models, acquiring the measured values of astronomy and radio navigation subsystems, and carrying out filtering estimation to obtain the position of the detector in an inertia coordinate system treating a target heavenly body as a center and the speed of the detector; and establishing the ephemeris error state model and the measurement model of the target heavenly body based on the position and the speed, obtaining the ephemeris error measurement value of the target heavenly body according to the estimation states of the two astronomy and radio navigation subsystems, utilizing a Kalman filtering method estimate the ephemeris error of the target heavenly body, feeding back to a navigation system model, and carrying out information fusion. The deep space detector astronomy/radio combination navigation method belongs to the technical field of spaceflight and navigation, can realize the online estimation of the heavenly body ephemeris error and the correction of the navigation system model error, and is suitable for the capture segment of a detector.

The invention discloses a convolution neural network compression method and a decompression method based on a compressed sensing principle. The compression method comprises a preprocessing step in which weights of layers in the convolution neural network are preprocessed to a series of matrix, a compression step in which the preprocessing result obtained in the preprocessing step is compressed toobtain a compressed weight, a training step in which the compressed weight is trained, a coding step in which the compressed weight trained in the training step is coded, and a model generation step in which a compressed convolution neural network model file is generated according to the coding result obtained in the coding step. Compared with other method, the convolution neural network compression method based on the compressed sensing principle has a higher compression ratio than the current popular direct pruning quantization method, and excessive information loss can be prevented throughkeeping low-frequency information in a frequency domain.

Micro-device bending forming method and device based on laser-assisted heating, involving micro-device manufacturing and micro-plastic forming technology, suitable for forming materials that are difficult or impossible to form by conventional micro-bending methods. The device includes a mounting platform, punch and die alignment Components, micro-bending forming components, feeding mechanism, loading mechanism, workpiece positioning components, laser heating system and control system, the laser beam emitted by the laser passes through the external optical path system to simultaneously perform non-contact quasi-static heating on both sides of the tiny workpiece, using laser The heat conduction makes the blank reach the forming temperature range; the laser heating system is combined with the micro-bending forming component, and the feeding and return of the punch is realized by the stepping motor drive, and the punch is loaded on the workpiece by the piezoelectric ceramic micro-driver, and the micro-bend is completed. Bending of devices. The invention reduces the influence of the temperature gradient on the forming precision. The device has reasonable design, simple process and good controllability, and is suitable for industrialized production.

The invention discloses an improved single-slope serial analog-digital converter, which comprises a ramp generator, a comparator, an adding counter and a system clock module; an output of the ramp generator is connected with an inverting input end of the comparator; an analog signal is connected with a non-inverting input end of the comparator; an output of the comparator is connected with an input end of the adding counter; and a control signal generated by the system clock module is respectively connected with the ramp generator and a clock control end of the adding counter. The phase and amplitude of a voltage ramp are adjusted by adopting a feedback mode, so that the influence of device parameter deviation on ramp voltage precision is reduced. The improved single-slope serial analog-digital converter overcomes the defect that the performance of the conventional single-slope serial analog-digital converter is influenced by an error of the ramp generator, and has conversion time thesame as that of the single-slope serial analog-digital converter. The improved single-slope serial analog-digital converter has a simple circuit structure; the whole system consists of elementary analog and digital modules; the design and analysis are quite simple; and the improved single-slope serial analog-digital converter is applicable to portable products in the pursuit of cost reduction andquick marketing.

The invention provides a real-time three-dimensional measurement method based on color sine structured light coding in the three-dimensional sending technology. In the method, a single color sine structured light coding pattern is projected to the surface of an object through a projector; two camera shooting devices are utilized to record distorted color structured light images respectively, all the color structured light images are subjected to color separation, and then single-color structured light images corresponding to an R channel, a G channel and a B channel are obtained; the phase positions of the two camera shooting devices are calculated according to the single-color structured light images; phase matching is conducted according to the epipolar constraint relation between the two camera shooting devices, and then instantaneous three-dimensional coordinates of the surface of the object are obtained. Through the real-time three-dimensional measurement method based on color sine structured light coding, real-time three-dimensional measurement can be achieved; the method has the advantages of being good in robustness to unbalance of color brightness, coupling of color channels, nonlinearity of the projector and other interference factors, high in measurement accuracy and the like.

The invention discloses a system for monitoring the voltage of a fuel battery, comprising a switch network unit, a data acquisition unit, an isolated communication interface unit and a main controller. The fuel battery is divided into a plurality of fuel battery sets; one fuel battery set together with the switch network unit, the data acquisition unit, the control unit and the isolated communication interface unit forms a voltage monitor module. The single batteries of the fuel battery unit is connected to the switch network unit which gates the single batteries one by one and transmit the a voltage signal to the data acquisition unit; the output end of the data acquisition unit is connected to the control unit which provides a voltage signal to the main controller through the isolated communication interface unit; the main controller provides a control signal to the control unit through the isolated communication interface unit to uniquely gate the monitor module. The invention reduces the monitoring cost and ensures effective monitor of the voltage of the fuel battery.

The invention relates to an image processing method and device, and belongs to the field of image processing. The method comprises the steps that at least two cluster sets are acquired, the at least two cluster sets include a first cluster set and a second cluster set, the first cluster set is the cluster set having identification information, the second cluster set is the cluster set without the identification information, each cluster set includes at least one face image, and the distance between all the face images in the same cluster set is not greater than a first preset threshold; the distance between the second cluster set and the first cluster set is determined; and the second cluster set and the first cluster set of which the distance is not greater than a second preset threshold are combined, and the second preset threshold is greater than the first preset threshold. The recall rate and the compression ratio of the clusters can be enhanced.

The invention relates to a deep space explorer acquisition phase celestial navigation method based on target object ephemeris correction. According to the method, firstly, a Martian explorer state model, a startlight angle navigation sub system measuring model and an X-ray pulsar navigation sub system measuring model are built; then, the startlight angle and the X-ray pulsar quantity measurements are respectively obtained; filtering estimation is performed to obtain the position and the speed of a detector in a heliocentric inertia coordinate system and a target object center inertia coordinate system; on the basis, a state model and a measuring model of target object ephemeris error are built; the quantity measurement about the target object ephemeris error is obtained through estimation state vectors of the startlight angle navigation sub system and the X-ray pulsar navigation sub system; a Kalman filtering method is used for estimating the target object ephemeris error; the target object ephemeris error is fed back into a navigation system model; the position of a target object in the navigation model is corrected. The deep space explorer acquisition phase celestial navigation method belongs to the technical field of aerospace navigation, can be used for estimating the object ephemeris error and correcting the model error of the navigation system on line, and is applicable to the explorer acquisition phase.

The invention discloses a ground reflector in a cable network structure. The ground reflector comprises a plurality of rectangular truss frame units (1), a plurality of ring structure connecting joints (2), a position and pitching control device (3), a feed source (4), an upper ring (5), a lower ring (6), a center cylinder (7), network surface cables (8), fastening cables (9) and dragging cables (11), wherein supporting cables (10) are mounted between the network surface cables and the fastening cables; the deformation of the network surface cables can be controlled by regulating the lengths of the supporting cables, and the shape of a reflecting surface is changed; through regulating and controlling the lengths of three telescopic rod units in the position and pitching control device, a position angle and a pitching angle of the ground reflector in the cable network structure satisfy the required positions and the required postures. The ground reflector is simple in structure and light and flexible, the position and the pitching of the ground reflector can be accurately controlled, the structural rigidity is improved, the surface accuracy of the reflector can be ensured, and the ground reflector is used for communication, navigation, detection, tracking, measurement and control for the ground surface environment.

The invention provides a double-frame control moment gyro high-precision frame rate servo system based on a harmonic reducer torsional rigidity hysteresis model. The double-frame control moment gyro high-precision frame rate servo system comprises a rate loop controller, a current loop controller, a power amplifier, a moment motor, a motor side photoelectric encoder, a harmonic reducer, a load side photoelectric encoder, a load, the harmonic reducer torsional rigidity hysteresis model and a compensation module, wherein the harmonic reducer torsional rigidity hysteresis model obtains an ideal input moment for restraining the hysteresis effect of the harmonic reducer by collecting torsion angle information at the current moment and historical moments; the compensation module changes a current to provide moment compensation for the system by contrasting the ideal input moment with an actual input moment. On the basis of the double-frame control moment gyro high-precision frame rate servo system, the harmonic reducer torsional rigidity hysteresis model is added for establishment and compensation, and therefore the effect, caused by the torsional rigidity hysteresis characteristic of the harmonic reducer, on the system accuracy can be reduced beneficially.

The invention relates to an automatic doffing trolley of a spinning machine. The automatic doffing trolley comprises a doffing trolley body and an automatic doffing device. The automatic doffing device is arranged on a bottom plate located on the upper portion of the doffing trolley body. A pre-loosening mechanism of the automatic doffing device is arranged on the bottom plate of the doffing trolley body through a spring steel plate. A pre-loosening block is fixed on the spring steel plate. When the trolley moves forwards, the pre-loosening block moves forwards along with the trolley, is inserted into the lower end of a bobbin, and enables the lower end of the bobbin to ascend along an oblique plane of the pre-loosening block. Then, under the action of a plane cam, the pre-loosening block abuts against the lower end of the bobbin, moves upwards in the direction parallel to the axis of a spindle blade and enables the full bobbin to break away from the spindle blade under the blocking action of a spindle hook. The bobbin bounced upwards enters a manipulator device. The upper ends of claws of the manipulator device clamp the upper end, without yarn, of the full bobbin and then pull the full bobbin out. The pre-loosening force of the pre-loosening mechanism is parallel to the axis of the spindle blade and has little influence on a spindle bearing. The manipulator device clamps the upper end, without the yarn, of the bobbin, and the quality index of the yarn can not be influenced.

The invention discloses single-crystal bar disconnection cutting equipment. The single-crystal bar disconnection cutting equipment comprises a machine frame, a single-crystal bar feeding device, a cutting machine frame, a wire saw cutting mechanism, a single-crystal bar jacking device, a material collecting and conveying robot and a skip car, wherein the single-crystal bar feeding device can slide on an undercarriage for operation; the cutting machine frame is installed on the undercarriage; the wire saw cutting mechanism is installed on the cutting machine frame; and the single-crystal bar jacking device, the material collecting and conveying robot and the skip car can slide on the undercarriage. The single-crystal bar disconnection cutting equipment is characterized in that supporting roller assemblies are fixed to a base; clamping jaws of two movable clamping units are located above supporting rollers, and the clamping units can penetrate through the space below the cutting machine frame; the wire saw cutting mechanism achieves single-section cutting; servo motors drive speed reducers to drive gears to be engaged with racks so that a bar flotation jacking device can move; and the material collecting robot is located on the side face of the bar flotation jacking device. The single-crystal bar disconnection cutting equipment has the advantages that the clamping units and the single-crystal bar jacking device can be driven to move automatically through matching of the motors, the gears and the racks, the labor intensity of operators is low and the degree of automation is high; and diamond wires can be replaced conveniently, wire breaking cannot happen easily and the failure rate is low.

The invention provides a current sensor and a measuring apparatus. The current sensor includes a magnetic induction unit and a processing unit provided on the outside of the wire to be measured, the magnetic induction unit is used for sensing a magnetic field generated by a current flowing through the wire to be measured and obtaining an induced signal corresponding to magnetic field intensity; the input end of the processing unit is electrically connected with the output end of the magnetic induction unit to process the induced signal, and at least one pair of magnetic induction units are arranged on the outside of the wire to be measured, the processing unit obtains the value of the current flowing through the measured wire through differential operation based on the paired induced signals. The current sensor is high in measurement accuracy, high in anti-interference capability, and low in installation requirement.

The invention discloses a substation type precision compensation for a robot system with an additional external shaft, belongs to the technical field of industrial robot reverse calibration, and aims to solve the difficulty in compensating the error of the external shaft (guide rail) of the industrial robot. According to the method, based on a robot envelope line, the guide rail is divided into a plurality of substations and substation type compensation is performed. The method comprises the steps: a laser tracker is adopted to measure and recognize the error of the external shaft (guide rail) and the robot, and the compensation for the tail end error of the robot is completed through inputting corrected control commands into the robot. During measurement and recognition of the error of the external shaft, an auxiliary coordinate system is introduced so as to allow the measuring process to be simple and quick, and meanwhile to ensure the precision. Through test verification, the method can greatly improve the absolute positioning precision of the robot with the additional external shaft, so as to allow the robot to be suitable for wider applications.

The invention relates to a prestress steel rod intelligent anchoring system monitoring dynamic state of strengthening engineering preload. In the system, a steel rod, a supporting plate and a nut are implanted in a selected strengthening object, the embedded section of the steel rod and the strengthening object are combined and are tensioned into a prestress steel rod, an acceleration sensor and a vibration exciter are arranged at the top end of the exposed section of the prestress steel rod, the acceleration sensor is connected with an intelligent measuring cell, and a signal acquirer, a signal analyzing device, a multifunctional calculation program card, a rechargeable battery and a control main board are built-in in the system, the vibration exciter is utilized to cause the exposed section to vibrate, the control main board is operated, length L2 is input and the intelligent measuring cell is operated to convert a vibration electric signal into a natural frequency spectrum, thus acquiring the preload transmitted to the supporting plate by the prestress steel rod and realizing monitoring of dynamic state of strengthening engineering preload. The invention overcomes the defects that the existing detection method is high in cost and can not realize large-area detection on preload construction quality on site and anchor rod can not work, and the invention is applicable to preload anchoring system strengthening engineering requiring large-area monitoring.

The invention relates to a pavement safety detection system and a method based on a roadside device. The system is composed of a vehicle-mounted device and a roadside device. The vehicle-mounted device includes a vehicle positioning module, a pavement information extraction module, an ADAS map interface module, a vehicle-mounted communication module and a map conversion module. The roadside devicecomprises a pavement information fusion module and a roadside communication module. Vehicles obtain positions and postures of the vehicles through the vehicle positioning module, detect pavement environment through a vehicle-mounted laser radar, extract pavement information, generate a local pavement map, and send the positions and postures of the vehicles and the local pavement map to the roadside device. The roadside device receives positions and postures from the plurality of vehicles and the local pavement map, conducts fusion to obtains a global pavement map on an area where the roadsidedevice is located, and then publishes the global pavement map to vehicles in the area. The vehicles receive the global pavement map and convert the global pavement map into a vehicle coordinate system for driving decisions. The pavement safety detection system of the invention realizes the share of sensing ability in the plurality of intelligent vehicles, increases detection range of pavement safety, and improves driving safety of the vehicles.

The invention relates to a device and method for spinning a cylindrical titanium alloy part. The device comprises a spinning mould 1, a spinning wheel device 4, a fluted disc device 7 and a spinning lathe. The spinning mould 1 is mainly used for clamping the cylindrical spinning part 10 and limiting the flow of materials in the process of metal spinning. The fluted disc device 7 is used for fixing the cylindrical part in the process of metal spinning to prevent relative rotation between the cylindrical spinning part 10 and the spinning mould 1. The spinning wheel device 4 is used for applying spinning force to the cylindrical spinning part 10 in the process of metal spinning, so that plastic deformation is carried out on a titanium alloy spinning workblank, and the required shape and the required size of the cylindrical spinning part 10 are achieved. According to a method for manufacturing the cylindrical spinning part 10, before the spinning process, the spinning mould 1 and the cylindrical spinning part 10 are heated up to a certain temperature, the process of mould filling is completed, then spinning operation is carried out, after the spinning mould 1 and the cylindrical spinning part 10 are cooled, detaching is performed, and finally the high-precision high-quality cylindrical spinning part 10 is obtained.

The invention relates to a resetting device using flexible positioning and rigid clamping in combination and a positioning method thereof. The invention is characterized in that a cartridge comprises two to four radially-arranged positioning gears, the lateral side of each positioning gear is provided with a positioning slant surface, Z-direction stopping planes are arranged between two adjacent positioning gears, a workpiece supporting board is provided with positioning slots fit with the positioning gears and positioning planes fit with the Z-direction stopping planes, a pop-rivet comprises a pop-rivet body which is connected with the workpiece supporting board by bolts, the pop-rivet orifices on the cartridge is provided with positioning cone surfaces, the lateral side of the pop-rivet body is provided with cone-shaped positioning contact planes fit with the positioning cone surfaces. The device can simultaneously realize precise resetting and rigid clamping, and ensure high safety and reliability of mechanical processing and high manufacture preciseness and efficiency of the processed object.