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1431results about "Navigation by terrestrial means" patented technology

Orientation and navigation for a mobile device using inertial sensors

A mobile device for enhanced navigation and orientation including a visualization interface, a first sensor for providing signals indicative of a movement of the mobile device, a second sensor for providing further signals indicative of a movement of the mobile device, and a processor receiving signals from the first and second sensors, calculating a position and an orientation of the mobile device from the received signals, and generating a real time simulation of an environment via the visualization interface based on the position and orientation of the mobile device. According to an embodiment, the first and second sensors are implemented as an inertial sensor and a GPS receiver, respectively.
Owner:ROBERT BOSCH GMBH

Noise pattern acquisition device and position detection apparatus provided therewith

A noise pattern acquisition device includes: a geomagnetic sensor; a coordinate estimation unit configured to estimate current position coordinates; and a geomagnetic noise pattern management unit configured to, when an abnormality occurs in a magnetic field strength detected by the geomagnetic sensor during movement of the noise pattern acquisition device, store in a geomagnetic noise pattern storage unit a geomagnetic noise pattern which is a pattern representing a time-series change of the magnetic field strength detected by the geomagnetic sensor. This makes it possible to not only acquire a geomagnetic noise pattern but also detect a proper position with a simple structure and process at reduced cost.
Owner:PANASONIC INTELLECTUAL PROPERTY CORP OF AMERICA

Human body attitude calculation method based on quaternion and Kalman filtering

The invention discloses a human body attitude calculation method based on quaternion and Kalman filtering. The method comprises determining a vector coordinate system and a navigation coordinate system, determining an attitude matrix, respectively acquiring accelerated speed, angular velocity and magnetic induction intensity signals through an accelerometer, a gyroscope and a magnetometer, carrying out initial alignment on a human body attitude detection system, calculating initial attitude angles such as a pitching angle, a rolling angle and a heading angle, transforming the initial attitude angles into initial quaternion, carrying out system modeling according to a quaternion differential equation, inputting the initial quaternion as a measured value, carrying out data fusion on the attitude data through a Kalman filtering algorithm, outputting an estimated value which is updated quaternion, carrying out normalization processing on the updated quaternion to obtain final posture information, updating the attitude matrix and acquiring updated attitude angles. The human body attitude estimation method effectively improves the accuracy of human posture detection, has a fast response speed, has good stability and instantaneity and has a broad application prospect.
Owner:NANJING UNIV OF SCI & TECH

Systems and methods for adjusting programming thresholds of polymer memory cells

Systems and methodologies are provided for adjusting threshold associated with a polymer memory cell's operation by applying thereupon a regulated electric field and / or voltage pulse width, during a post fabrication stage. Such customization of programming thresholds can typically be obtained at any cycle of programming the memory cell, to increase flexibility in circuit design. Accordingly, the present invention supplies both a current-voltage domain, and / or a frequency-time domain, to facilitate adjusting the program thresholds of the polymer memory cell.
Owner:MONTEREY RES LLC

Pedestrian inertial positioning system based on indoor magnetic field feature assistance

The invention provides a pedestrian inertial positioning system based on indoor magnetic field feature assistance. The system comprises a magnetic field and inertial data obtaining module, a magnetic field positioning module, a pedestrian dead reckoning module, a positioning fusion module and an output module, wherein the magnetic field and inertial data obtaining module is used for acquiring magnetic field, accelerated speed and angular velocity information; the magnetic field positioning module is used for building a magnetic field feature library and carrying out time-frequency analysis on the magnetic field vector sequence in real time to extract the time-frequency feature, and matching with the magnetic field feature library to carry out magnetic field feature positioning; the pedestrian dead reckoning module is used for updating accelerated speed and angular velocity zero offset according to the condition that the step velocity discontinuity is zero during walking, judging the step number and calculating the step length and the direction of each step; the positioning fusion module is used for fusing a magnetic field feature positioning result and a pedestrian dead reckoning inertial positioning result by means of particle filter; and the output module is used for displaying a positioning result on web pages and terminals. The system provided by the invention has the characteristics of being independent from beacon during positioning, low in cost and consumption of positioning terminals, accurate in positioning result and adaptive to environment change.
Owner:MEDIASOC TECH

Solid state orientation sensor with 360 degree measurement capability

The device is a miniature, self-contained solid state orientation sensor. The unit utilizes three magnetometers and three accelerometers to calculate pitch, roll, and yaw (compass heading) angles relative to the earth's magnetic and gravitational fields. The three orientation angles are output in digital RS232 or optional multi-drop RS485. The device can also be programmed to provide raw accelerometer and magnetometer data in true physical units. The device is capable of measuring angles from 0 to 360 degrees on the yaw axis, 0 to 360 degrees on the pitch axis, and −70 to +70 degrees on the roll axis. The yaw output is compensated for errors due to pitch and roll using embedded algorithms. Applications include fast solid state compassing, robotics, virtual reality, down-hole well drilling, and body position tracking for biomedical and multimedia applications.
Owner:LORD CORP

Utilizing magnetic field based navigation

There is provided a solution comprising detecting that a positioning device is within a predetermined control area associated with a building, acquiring a first sequence of magnetic field measurements carried out by the positioning device, wherein the first sequence represents at least one of the magnitude and the direction of Earth's magnetic field; determining that an operational environment of the positioning de-vice has changed between an indoor environment and an outdoor environment when a at least one predetermined criterion with respect to the first sequence is met; and causing actuation of a predetermined software function in or with respect to the positioning device when the operational environment of the positioning device has changed.
Owner:INDOORATLAS

Geophysics-based method of locating a stationary earth object

A geophysics-based method for determining the position of a stationary earth object uses the periodic changes in the gravity vector of the earth caused by the sun- and moon-orbits. Because the local gravity field is highly irregular over a global scale, a model of local tidal accelerations can be compared to actual accelerometer measurements to determine the latitude and longitude of the stationary object.
Owner:NAT TECH & ENG SOLUTIONS OF SANDIA LLC

Wireless communication terminals and methods that display relative direction and distance therebetween responsive to acceleration data

Wireless communication terminals are disclosed that display the direction and distance between them so that users can, for example, travel away from each other and then later find one another. The terminals are configured to track their movement using acceleration data. Some of the terminals may operate as slave terminals in which they transmit their movement data to a master terminal which determines therefrom the relative direction and distance between the terminals. The master terminal may then transmit the relative direction and distance data to the slave terminals where it can be displayed to their users.
Owner:SONY ERICSSON MOBILE COMM AB

Attitude estimation method of maneuvering acceleration-assisted extended Kalman filter (EKF) attitude and heading reference system (AHRS)

The invention provides an attitude estimation method of a maneuvering acceleration-assisted extended Kalman filter (EKF) attitude and heading reference system (AHRS). The state quantity of the EKF contains an error of three attitude angles, a null bias error of a three-axis gyroscope and a three-axis carrier maneuvering acceleration error of a carrier system, and the observed quantity of the EKF contains a three-axis acceleration error and a three-axis earth magnetic field error. A strapdown attitude algorithm and the nine-state EKF algorithm are subjected to data fusion to acquire attitude estimation of the AHRS. A single-axis turntable experiment, a vehicle-mounted dynamic experiment and a flight experiment prove that the maneuvering acceleration-assisted nine-state EKF data fusion algorithm has stable attitude angle accuracy under different maneuvering conditions, and the mean square deviation of the attitude angle can be limited within 2 degrees.
Owner:BEIHANG UNIV

Self-adaptation three-dimensional attitude positioning method based on microinertia and geomagnetic technology

The invention discloses a self-adaptation three-dimensional attitude positioning method based on microinertia and a geomagnetic technology, comprising the following steps of: (1) inducing a motion attitude of a carrier by utilizing a sensor of a microinertia measuring device; (2) setting an initial attitude of the microinertia measuring device and accelerated speed and geomagnetic field information under a global coordinate system; (3) solving the attitude value of the microinertia measuring device; (4) predicting the attitude value of the microinertia measuring device by utilizing triaxial micro-gyroscope sensor data; (5) carrying out confidence judgment on the triaxial micro-acceleration sensor data and triaxial magnetic field sensor data, detecting the interference of a surrounding environment, and setting self-adaptation parameters; (6) obtaining the attitude error value of the microinertia measuring device by utilizing the triaxial micro-acceleration sensor data and the triaxial magnetic field sensor data which are processed in the step (5); (7) fusing the attitude predictive value obtained from the step (4), corrected information obtained from the step (6) and the self-adaptation parameters obtained from the step (5) to obtain the attitude value of the microinertia measuring device; and (8) outputting attitude information.
Owner:INST OF AUTOMATION CHINESE ACAD OF SCI

Input device for using geomagnetic sensor and a method thereof for generating input signal

An input device using a geomagnetic sensor includes a geomagnetic sensor outputting a voltage corresponding to geomagnetism, and a control part calculating an azimuth using the voltage output from the geomagnetic sensor and calculating the rotation angle by comparing the azimuth to a previously measured azimuth, thereby generating the input signal corresponding to the rotation angle when the input device is tilted within a certain range. Accordingly, unwanted generation of the input signal is prevented when the input device is tilted by more than a certain angle.
Owner:SAMSUNG ELECTRONICS CO LTD

Hand movement tracking system and tracking method

The invention discloses a hand movement tracking system and a hand movement tracking method. The invention comprises an attitude and heading reference system based on an accelerometer, a gyroscope and a magnetic sensor, and a hand movement tracking method based on the attitude and heading reference system. The hand movement tracking method comprises the following steps: firstly, obtaining a triaxial acceleration measured by the accelerometer, a triaxial angular velocity measured by the gyroscope and a triaxial magnetic-field component measured by the magnetic sensor, performing error compensation on the magnetic sensor by adopting a least square method to establish an error model after an upper computer receives sensor data, eliminating high-frequency noise of the triaxial acceleration by virtue of a window low-pass filter, and establishing an error model for the gyroscope so as to perform error compensation on random drift of the gyroscope; secondly, effectively integrating the gyroscope, the accelerometer and the magnetic sensor by virtue of an improved adaptive complementary filtering algorithm to obtain an attitude angle and a path angle; and finally, performing gravity compensation and discrete digital integration on acceleration signals to obtain a velocity and a track of a hand movement. The tracking system and the tracking method disclosed by the invention can be applied to a man-machine interactive system, is convenient to operate, and is strong in experience feeling.
Owner:ZHEJIANG UNIV

Indoor magnetic field based location discovery

There is provided an apparatus, wherein the apparatus is caused to acquire a location estimate of a positioning device that is to determine its location inside a building, wherein the location estimate is acquired on the basis of an indoor non-magnetic field based location discovery system; access an indoor Earth's magnetic field, EMF, map of plurality of buildings, wherein the indoor EMF map represents at least one of magnitude and direction of the Earth's magnetic field affected by the local structures of a corresponding building; and select a part of the indoor EMF map on the basis of the location estimate of the positioning device, wherein the selected part of the indoor magnetic field map includes the indoor EMF map for the area in which the positioning device currently is.
Owner:INDOORATLAS

Geomagnetic indoor positioning system based on self-adaptive particle filter algorithm

The invention discloses a geomagnetic indoor positioning system and method based on a self-adaptive particle filter algorithm. The geomagnetic indoor positioning system comprises the novel self-adaptive particle filter algorithm and an efficient geomagnetic fingerprint data collecting unit. The efficient geomagnetic fingerprint data collecting unit has the main function of quickly collecting indoor geomagnetic signals by using a mobile phone magnetometer and converting the indoor geomagnetic signals into a geomagnetic fingerprint model to be stored. The novel self-adaptive particle filter algorithm is the improvement to an existing filter algorithm to improve the robustness, the precision and the usability. The key technology of the self-adaptive particle filter improvement algorithm mainly comprises a self-adaptive behavior model, a novel measurement model, a self-adaptive resampling model and a positioning precision estimation and positioning failure detection model. The geomagnetic indoor positioning system is suitable for various smart phones integrated with acceleration sensors, gyroscopes and magnetometers. The geomagnetic indoor positioning system has the advantages that the facing directions, the placing positions and using of the smart phones are not limited, and positioning precision is high.
Owner:NANJING UNIV

Navigation control method of underground automatic scraper

The invention discloses a navigation control method of an underground automatic scraper. The method comprises the following steps: firstly planning a target path; when a vehicle tracks the target path; according to the known initial deviation, forming a comprehensive feedback used as the input of a navigation controller, wherein the comprehensive feedback comprises the transversal position deviation, the course angle deviation and the course angle variation rate deviation; by combining the PID correction control, calculating the steering control command of the vehicle and inputting to an electro-hydraulic steering control system of the vehicle to change the steering angle of the vehicle; and accurately predicting the model by using the vehicle orbit formed in the navigation controller, and accurately calculating the deviation value between the track orbit and the target path of the vehicle; and then calculating new steering control commands by taking the deviation values as the feedback. By repeating the steps again and again, the vehicle can continuously track the target path, thereby realizing the automatic navigation of the underground scraper.
Owner:BGRIMM MACHINERY & AUTOMATION TECH CO LTD

Generating magnetic field map for indoor positioning

There is provided an apparatus caused to acquire information indicating a measured magnetic field vector and information relating to an uncertainty measure of the measured magnetic field vector in at least one known location inside the building, wherein the indicated magnetic field vector represents magnitude and direction of the earth's magnetic field affected by the local structures of the building, and to generate the indoor magnetic field map for at least part of the building on the basis of at least the acquired information and the floor plan.
Owner:INDOORATLAS

Three dimensional feature location from an excavator

A combination of location measurement apparatuses to measure in three dimensions the location of an excavator with respect to a job site, and to further measure the location of an excavated or a topographical feature with respect to the excavator by range finding from the excavator in proximity of the feature and contemporaneously recording measurement data on a computer.
Owner:DEERE & CO

Indoor positioning system and indoor positioning method based on three-dimensional multipoint wireless and micro-inertia navigation

The invention disclose an indoor positioning system and an indoor positioning method based on three-dimensional multipoint wireless and micro-inertia navigation as well as an expansion type indoor control system. The indoor positioning system comprises a calibration device and a sensing device, wherein the calibration device comprises at least three first wireless transceiver units used for sending signals at intervals of first preset time; and the sensing device comprises an inertia sensing unit, a second wireless transceiver unit and a processing unit, wherein the inertia sensing unit is used for sensing the motion of a target object, the second wireless transceiver unit is used for producing a response signal when receiving the signal transmitted by each first wireless transceiver unit, and the processing unit is used for respectively calculating a first space coordinate of the target object according to the motion of the target object sensed by the inertia sensing unit, calculating a second space coordinate of the target object according to the response signal, and combining and processing the first space coordinate and the second space coordinate to obtain the final space coordinate of the target object. With the adoption of technical schemes of the indoor positioning system and the indoor positioning method, the positioning accuracy is high, and the motion response of the target object is sensitive, and the response rate achieves the millimeter.
Owner:SHENZHEN HEZHI CHUANGYING ELECTRONICS

Carrier attitude measurement method and system

The invention discloses a method and system of measuring carrier attitude, which comprises data processing device and sensor composed of three axis accelerometer, three axis flux meter, three axis rate gyroscope for measuring acceleration of gravity, earth magnetic flux density, the component of the carrier's angular speed on the coordinate system individually. When processing the signal, use the component of the carrier's angular speed to Kalman filtering the measured acceleration of gravity and earth magnetic flux density and get the estimated value by which resolve the carrier attitude. The invention can reduce the impact of the system causing by acceleration through stabilizing gyroscope signal and do not have the problem of integral float, the sensor using MEMS integrated chip technology.
Owner:TSINGHUA UNIV

Three-dimensional motion tracking system and method based on inertial sensor and geomagnetic sensor

The invention relates to the technical field of measurement positioning, in particular to three-dimensional motion tracking system and method based on an inertial sensor and a geomagnetic sensor. In the invention, the motion tracking is carried out by using a mode of combining the inertial sensor with the magnetic sensor; a stable calibration reference is constructed by utilizing the gravity acceleration and geomagnetic lines so as to further obtain an accurate object real-time attitude; and the interference with an output signal of an acceleration sensor from the gravity acceleration is rejected according to the real-time attitude to obtain accurate object motion acceleration data which is used for computing and acquiring object position information. By carrying out computing treatment on sensor data and accurate calibration on errors, the invention realizes the object positioning tracking in the three-dimensional space and has higher tracing precision and boarder popularization and application range.
Owner:WUHAN UNIV

Whole attitude angle updating method applied to agricultural machinery and based on nine-axis MEMS (micro-electromechanical system) sensor

The invention discloses a whole attitude angle updating method applied to agricultural machinery and based on a nine-axis MEMS (micro-electromechanical system) sensor. The whole attitude angle updating method applied to agricultural machinery and based on the nine-axis MEMS sensor comprises the following steps: a gyroscope error model, an electronic compass calibration ellipse model and a seven-dimensional EKF (extended Kalman filter) model are established, and parameter vectors of corresponding motion attitudes of a vehicle body are set; data including the acceleration, the angular velocity and the geomagnetic field intensity of vehicle body motion are acquired in real time; the angle, the speed, the location information and the heading angle of the vehicle body are calculated through the established gyroscope error model and electronic compass calibration ellipse model; data fusion processing is performed on the angle, the speed, the location information and the heading angle of the vehicle body through the seven-dimensional EKF model, and the motion attitude angle of the vehicle body is updated in real time. The method comprising the steps has small errors and high precision and is stable and reliable.
Owner:SHANGHAI HUACE NAVIGATION TECH

Combined initial alignment system and alignment method for strapdown inertial navigation system of underground coal mining machine

ActiveCN105371871AHigh positioning accuracyAddresses difficulty relying on external positioning systems for initial alignment of SINSNavigation by terrestrial meansNetwork topologiesWireless sensor networkingEngineering
A combined initial alignment system and alignment method for a strapdown inertial navigation system of an underground coal mining machine belong to initial alignment system and alignment method for positioning navigation of underground coal mining machines. The system is composed of a strapdown inertial navigation system installed on the coal mining machine, a wireless sensor network mobile node, an inclination sensor, a geomagnetic field sensor and anchor nodes installed on a hydraulic support. After coarse alignment of the strapdown inertial navigation system, the wireless sensor network is used to detect the location information of the underground coal mining machine, the inclination sensor measures the roll and pitch angle, and the geomagnetic field sensor measures the yaw angle. A pose measurement equation of the coal mining machine is constructed, and the pose measurement equation is combined with an error model after the coarse alignment of the strapdown inertial navigation system to establish a state equation; fusion smoothing is carried out to obtain the accurate location information of the coal mining machine; and the precise alignment of the strapdown inertial navigation system is conducted to complete the initial alignment. The invention realizes precise initial alignment of strapdown inertial navigation combination under the severe closed condition in coal mine, and greatly improves the precision of the integrated positioning under large misalignment angle of the strapdown inertial navigation system of the coal mining machine.
Owner:CHINA UNIV OF MINING & TECH

Unmanned aerial vehicle finding device and method

The invention discloses an unmanned aerial vehicle finding device and method, belonging to the field of an unmanned aerial vehicle. the method comprises the steps of: timely acquiring and storing flying position information of an unmanned aerial vehicle through a wireless network; when receiving a request for finding out the unmanned aerial vehicle, reading the finally stored position information of the unmanned aerial vehicle to locate the position in which the unmanned aerial vehicle is; outputting the position in which the unmanned aerial vehicle is. By adopting the method and device disclosed by the invention, the landing or falling position range of the unmanned aerial vehicle can be located according to the finally stored position information under the situation of flying to lose through recording the position information in the flying process of the unmanned aerial vehicle, so as to reduce the search range and find out the unmanned aerial vehicle and further reduce the economic loss.
Owner:SZ DJI TECH CO LTD

Method for autonomous navigation using geomagnetic field line map

InactiveCN101520328ATake advantage ofUsing multiple characteristic quantities of the geomagnetic field to jointly match fullyInstruments for comonautical navigationNavigation by terrestrial meansTerrainCruise missile
The invention discloses a method for autonomous navigation using a geomagnetic field line map. Firstly, a plurality of characteristic quantities of the geomagnetic filed on a path of an aerial vehicle are measured continuously according to a preset frequency, and measurement data are used to build a matched line map of the corresponding characteristic quantities in a sliding window mode with fixed-point number; and a matched line map of the plurality of characteristic quantities is matched and compared with a reference map by using an algorithm for fining global optimum according to a matching similarity rule and a matching result fusion rule to acquire the position information of the aerial vehicle. The technology makes full use of the characteristics of the plurality of characteristic quantities of the geomagnetic field to calculate the accurate position of the aerial vehicle, avoids navigation accumulated error under a condition of long flight period, is particularly suitable for navigation in environments without typical geomorphic features such as ocean and plain, can meet requirements of future cruise missiles, unmanned aerial vehicles, submarines and the like for passive, all-sky time, all-weather and all-terrain navigation, and also can be used in civil area.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Underwater carrier geomagnetic anomaly feature points matching navigation method

An underwater carrier geomagnetic anomaly feature points matching navigation method belongs to the technical field of underwater navigation and solves the problem in the prior art that the location of an underwater carrier can not be determined according to geomagnetic field information. The method provided by the invention comprises the following steps of: acquiring a target magnetic moment vector of present position of the underwater carrier and a relative position vector from the present position of the underwater carrier to a target magnetic source; constructing a map of the underwater target magnetic source; carrying out coordinate transformation based on the absolute position of the underwater carrier so as to obtain geographic coordinates of the map; calculating the position of the underwater carrier in the map at sampling time and the geographic coordinates of the underwater carrier at the sampling time; updating the position of the target magnetic source; updating the map of the underwater target magnetic source; and repeating the above relative processes to complete the matching navigation of the underwater carrier. The invention is suitable for underwater carrier navigation.
Owner:NORTHEAST FORESTRY UNIVERSITY

Methods of Measuring the Position and Orientation of Objects

The invention discloses a method for measuring the position and the azimuths of an object. In the process of measuring the azimuths of the object, the first azimuth is calculated according to a measurement result acquired from a three-axis gyroscope; the second azimuth is calculated by the three-axis acceleration sensor only when the object is in a stationary state; the third azimuth is calculated by the three-axis geomagnetic sensor when the object is in the stationary state or when the object continuously moves within a certain period of time; and the second azimuth and the third azimuth are corrections to the first azimuth. The traditional method for measuring the azimuths of the object only makes use of the three-axis gyroscope, which can generate accumulative errors and cause that the measurement result is inaccurate for a long time. According to the invention, on the basis of use of the three-axis gyroscope, the three-axis acceleration sensor and the three-axis geomagnetic sensor are used for correcting the measurement result of the azimuths, acquired from the three-axis gyroscope, and therefore the more accurate azimuths of the object can be acquired.
Owner:鼎亿数码科技(上海)有限公司 +1

Robot positioning method based on wireless sensor network and geomagnetic map

The invention relates to a robot positioning method based on a wireless sensor network and a geomagnetic map. wireless sensor network nodes, during the movement of the robot, by activating A wireless sensor network node, use RSSI to obtain the observation model of wireless sensor network nodes and robots; then use PSO and multi-sensor information fusion to obtain the particle likelihood; at the same time obtain the weight of particles in the particle swarm optimization method; Resampling and fitness function judgment are used to obtain the position of the optimal particle, obtain a local geomagnetic map, and use the geomagnetic matching method to achieve precise positioning, and finally obtain the absolute position. The present invention is easy to associate data, no wrong association occurs during observation, and the robustness and accuracy of the network are improved; at the same time, a more realistic system state distribution prediction is obtained, which makes the positioning of the robot more accurate and reduces the calculation amount of geomagnetic matching. The real-time performance of the method is increased.
Owner:WUHAN UNIV OF SCI & TECH

Method and system for locating and navigating a target

Techniques and methodologies are disclosed for minimizing inaccuracies in distance measurements and location determinations for autonomous vehicles or targets ranging to subsets of beacons. Such techniques and methodologies can be used to better control (e.g., navigate) an autonomous vehicle in an area and / or along a pathway, or trajectory.
Owner:HAILO TECH LLC

Systems and methods for terrain warning suppression using flight plan information

A method according to an aspect of the present invention includes determining if terrain presents a hazard to an aircraft based on the current position of the aircraft and the intended flight plan for the aircraft and providing an alert if it is determined that the terrain presents a hazard to the aircraft. The method may be employed in any situation to achieve any result, such as when the aircraft is in a low-RNP environment to prevent nuisance terrain alerts.
Owner:AVIATION COMM AMP SURVEILLANCE SYST LLC
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