311 results about "Kinematic chain" patented technology

The invention relates to the technical field of robot anomaly prediction, in particular to a robot anomaly prediction method and system based on multi-dimensional fusion and causal inference. The method comprises the steps of performing multi-scale depth state characterization based on acquired robot multi-joint sensing data, and performing dynamic causal graph fusion based on the multi-scale depth state characterization. Comprising the steps of priori knowledge graph construction based on a kinematics chain, dynamic association attention mechanism construction based on data driving, state fusion of knowledge and attention guidance and global state vector generation. Performing hierarchical space-time dependency prediction based on the fused features, wherein the hierarchical space-time dependency prediction comprises robot joint topological graph construction, spatial dependency dynamic modeling, long-range time evolution prediction and future robot health state prediction; the method shows excellent performance in a plurality of core dimensions such as prediction precision, early warning timeliness and diagnosis interpretability, and has extremely high actual deployment value and engineering popularization potential.

The invention discloses a dynamic control method for a complex curved surface five-axis numerical control machining tool vector, which comprises the following steps of: scanning the surface of a target workpiece by using a high-precision three-dimensional scanner to obtain point cloud data; based on the point cloud data, establishing a mathematical model S (u, v) of the target complex curved surface; a mathematical model based on the target complex curved surface; establishing a comprehensive dynamic model of the five-axis numerical control system; optimizing the initial tool posture in combination with the kinetic model; collecting dynamic operation data of the cutter and the workpiece; on the basis of the dynamic operation data, a model predictive control (MPC) algorithm is used for adjusting the machining path and the cutter direction in real time; according to the method, a comprehensive dynamic model of a five-axis numerical control system is established, dynamic coupling effects of a machine tool kinematic chain, cutter flexibility, cutting force, a temperature field and a stress field are brought into a unified framework, and complex dynamic behaviors are accurately described and controlled through multi-body dynamic modeling and an optimization algorithm.

The invention discloses a charging robot automobile charging port pose vision measurement method comprising the following steps: 1, controlling a mechanical arm to drive a monocular camera to collect a charging port image, and constructing a charging port image data set; 2, extracting a charging hole contour in each image by adopting an improved Mask R-CNN instance segmentation model; step 3, performing robust ellipse fitting based on each charging hole contour to obtain center coordinates of each charging hole in the two-dimensional image; step 4, establishing a world coordinate system based on charging hole space distribution defined by the automobile charging port standard model, and determining three-dimensional coordinates of each charging hole; and 5, the multi-view two-dimensional center coordinates and the corresponding three-dimensional coordinates are input into the PnP graph optimization model, and the pose of the charging port in the mechanical arm base coordinate system is solved by fusing the re-projection error constraint, the structure prior constraint and the kinematics chain constraint. The invention further discloses a charging robot automobile charging port pose vision measurement charging method and a charging system.

The invention discloses a precision compensation method of a composite numerical control machine tool, and particularly relates to the technical field of precision control of the numerical control machine tool, which comprises the following steps: synchronously acquiring temperature, vibration and force information under the driving of a unified clock through multiple types of sensors deployed at key nodes of the machine tool, and generating a synchronous multi-source sensing data set with aligned timestamps; inputting the data set into a multivariable coupling error model obtained through data driving training, and calculating and generating a comprehensive space volume error predicted value of a tool nose point of the tool; performing inverse calculation based on a machine tool kinematic chain model, and generating a multi-dimensional micro-compensation instruction set containing the compensation amount of each motion axis and the sequential relationship; and finally, dynamically writing the instruction set into a servo control ring of the numerical control system through a real-time data interface, and driving each motion shaft to execute synchronous compensation motion. According to the method, comprehensive compensation of multi-physics field coupling errors such as temperature, vibration and force load is achieved, and the machining precision and stability of the numerical control machine tool under complex working conditions are improved.

The invention relates to the technical field of robot intelligent control, in particular to a humanoid robot multi-modal environment sensing and self-adaptive chassis control method, which comprises the following steps: monitoring a contact force vector and a sliding trend in real time through a multi-dimensional touch sensor, mapping pose drift to a chassis coordinate system based on a Lie group constraint space-time synchronization layer, and performing multi-modal environment sensing and self-adaptive chassis control on the basis of a multi-dimensional touch sensor; a compensation vector is generated, a three-level tactile response layer dynamic switching force / bit mixed impedance mode is adopted, reverse translation of an omnidirectional chassis is combined to counteract drift, compensation parameters are optimized through a depth deterministic strategy gradient algorithm, and the system ensures control instruction time sequence alignment through a time-space stamp synchronization engine. The attitude oscillation in the compensation process is suppressed by using the inertial measurement unit, the obstacle avoidance interference domain is constructed based on the kinematics chain of the operation arm, and the compensation trajectory is smoothed by using the B-spline curve, so that the precision, stability and safety of the humanoid robot in the complex contact operation are improved, and an efficient and reliable solution is provided for a man-machine cooperation scene.

The invention relates to the technical field of numerical control machine tool error compensation, in particular to a space geometric error iterative compensation method and system of a five-axis numerical control machine tool. The method comprises the following steps: constructing a tool kinematic chain topology model and a workpiece kinematic chain topology model of the five-axis numerical control machine tool, and establishing a theoretical forward kinematic model and an actual forward kinematic model of a tool relative to a workpiece; measuring and identifying the geometric error of each motion axis of the five-axis numerical control machine tool; separating a cutter shaft direction vector part and a cutter point position part during iteration; calculating the pose deviation of the cutter according to the cutter shaft direction vector and the correction model of the cutter point position; and continuously iterating to generate a correction operation position of each axis, and realizing error compensation of the tool space pose of the five-axis linkage numerical control machine tool. According to the method, the actual space pose of the cutter is directly corrected through the iterative algorithm in the offline state, so that the actual space pose continuously approaches the theoretical pose, and the error compensation precision and efficiency are improved.

The invention discloses a virtual assembly and anti-collision simulation method for a double-swing-head five-axis numerical control machine tool, and the method comprises the following steps: S1, building a geometric model of the double-swing-head five-axis numerical control machine tool based on a machine tool kinematic model, and the geometric model comprises parameterized three-dimensional models of a main shaft part, a swing head mechanism, a workbench and a machine tool body; s2, according to the constraint relation of the kinematic chains of the machine tool, an assembly hierarchical relation is established in the virtual environment, and virtual assembly of all parts is achieved through dynamic constraint driving; s3, on the basis of a machine tool kinematics forward and inverse solution algorithm, simulating the motion trail of the double swing heads in the five-axis linkage process; s4, through a real-time collision detection algorithm, detecting interference conditions among the cutter, the swing head, the workpiece, the clamp and the machine tool body, and generating an anti-collision early warning signal; and S5, optimizing a motion path of the machine tool in combination with a simulation result, and outputting a collision-free machining code. The assembly precision can be improved, and the physical debugging cost can be reduced.

The invention discloses a knee joint postoperative rehabilitation management system, which comprises the steps of building a hip-knee-ankle multi-joint associated diagnosis AI model, generating an evaluation result based on the hip-knee-ankle multi-joint associated diagnosis AI model, generating a staged rehabilitation scheme through reinforcement learning and a rehabilitation knowledge graph, and performing rehabilitation management on the rehabilitation scheme. Sensor data in the training process of a patient is collected through a detection suite and input into an action judgment model after being preprocessed, and the model outputs an action correctness score and an error type in combination with a shank-thigh axis consistency judgment algorithm and an action standard library; according to the action correctness score and the error type, the patient is guided to adjust the action, and rehabilitation training closed-loop management is achieved. The knee joint compensation relation can be accurately judged, the kinematic chain balance principle of knee rehabilitation training can be met, the correctness of actions during training can be accurately judged, and joint unbalance is avoided.

The invention provides a self-supervised continuous 3D hand posture tracking method based on a lightweight inertial measurement unit, and the method specifically comprises the following steps: firstly, obtaining a hand motion signal by using a lightweight consumer-level IMU, and extracting features by using a multi-stage neural network containing a bidirectional long-short term memory (Bi-LSTM) module; the global displacement and orientation of the hand are processed through a wrist posture estimation module, and three-dimensional coordinates of hand skeleton points are solved and calculated by means of a finger motion chain; secondly, a self-supervised completion network is realized by combining a random mask and dual loss, and the features are processed to complete complete attitude reconstruction; and finally, combining network output with kinematics prior, generating a three-dimensional grid with reasonable anatomy, solving the problem that joint deformation is inconsistent with torque, and realizing accurate acquisition of a three-dimensional hand posture. For a dynamic hand motion tracking task, the method can adapt to a sparse IMU deployment scene and realize continuous high-precision tracking; the real-time performance demand of daily interaction can be met, and a low-cost solution can be provided for the fields such as medical rehabilitation and virtual interaction which have strict requirements on attitude precision.

The invention relates to the technical field of rehabilitation medical treatment, and discloses a muscle group stress analysis method and device, a terminal and a storage medium, and the method comprises the steps: respectively obtaining motion data collected by inertial measurement units arranged on the body of a user, and recognizing gait events based on the motion data corresponding to the inertial measurement units of the lower limbs, dividing the continuous motion data into a plurality of gait cycles according to the gait event; fusing the motion data acquired by each inertial measurement unit to obtain a three-dimensional posture of each preset segment of the body, and constructing a three-dimensional motion track of the spine area of the user in combination with a human kinematics chain model; processing the three-dimensional motion track and the known muscle group stress data by adopting a singular value decomposition embedding regression method to obtain a preliminary target muscle group stress curve of each gait cycle; and correcting the initial target muscle group stress curve based on a human body multi-rigid-body dynamic model in combination with a control cost function to obtain a final target muscle group stress curve.

The invention discloses a face gear worm grinding machine geometric-thermal error compensation system based on digital twinning. The face gear worm grinding machine geometric-thermal error compensation system comprises a geometric-thermal error mapping model, a thermal error prediction model and a digital twinning driving geometric-thermal error compensation system. The geometric-thermal error mapping model is constructed based on a mapping relation between geometric-thermal errors and tooth surface errors in a grinding machine kinematic chain; the thermal error prediction model is constructed based on an LSTM network of an improved gating structure; the digital twin drive geometric-thermal error compensation system comprises a layered architecture of a sensing control layer, an edge layer and a cloud layer. The sensing control layer is used for collecting data in real time so as to provide heat information data of the face gear worm grinding machine. An edge layer deploys a thermal error prediction model to carry out real-time thermal error prediction, and the thermal error prediction model is integrated with a geometric-thermal error mapping model; and the cloud layer trains a thermal error prediction model through historical thermal information data, and issues updated model parameters to the edge layer to synchronously update the thermal error prediction model.

This device includes a base, a handle lever mounted so as to pivot on the base about an axis, a kinematic chain configured to transmit a movement of the handle lever to a lock of the opening control to unlock the door, an inertial safety member having a main body forming an inertial mass and a main locking element connected to the body and configured to pass, by inertia effect in the event of impact, from an inactive idle position to at least one active position of locking at least one movable element of the kinematic chain. The inertial member is movably mounted so as to pivot on the base about a second locking axis and is configured to operate in a reversible mode by adopting at least one reversible locking position and to operate in an irreversible mode by adopting at least one irreversible locking position.

The invention provides a master-slave type double-arm force-position hybrid control method for deboning a tail wishbone, which comprises double mechanical arms consisting of a master arm and a slave arm. The method comprises the following steps of: establishing pose constraints and motion constraints between the tail wishbone and the master arm as well as between the master arm and the slave arm; therefore, a closed kinematic chain is formed between the double mechanical arms and the tail wishbone, and the slave arm moves along with the master arm; according to the tail wishbone deboning segmentation plane and the closed kinematic chain, a position control equation of a mechanical arm operation space is obtained; the force control rate of the tail wishbone is obtained according to the stress of the tail wishbone, and the position control equation and the force control rate form a force-position mixed control law; carrying out constraint analysis on a tail wishbone meat segmentation plane, and determining a deboning path and deboning directions of all points of the path; in the task of removing the tail wishbone, the two arms are subjected to master-slave force position mixed control, the master arm tightly holds the tail wishbone, and the slave arm carries out accurate deboning operation.

The locking-mode driving-free spherical surface moving parallel robot comprises a fixed platform and a movable platform, and a first kinematic chain, a second kinematic chain, a third kinematic chain and a fourth kinematic chain are arranged between the fixed platform and the movable platform; the first kinematic chain comprises a first revolute pair R11, a second connecting rod, a second revolute pair R12, a third connecting rod, a third revolute pair R13, a fourth connecting rod assembly, a fourth revolute pair R14, a fifth connecting rod and a fifth revolute pair R15 which are connected in sequence, the fifth revolute pair R15 and the first revolute pair R11 are both connected with the fixed platform, and the fourth connecting rod assembly is further connected with a fifth ball pair S14; the fifth ball pair S14 is further connected with the movable platform. The robot does not need to be driven when being in a locked state, and under a set configuration, control driving and auxiliary driving are carried out, and the movable platform can be switched between a locking motion mode and a moving motion mode.

The invention provides a double-layer intelligent agent optimization method, device and equipment for multiple mechanical arms and a storage medium. An RRT-Connect algorithm and B spline track smooth optimization are introduced into a high layer, and global path planning is conducted on environment information of a carrying task; the smoothed centroid trajectory is converted into a reference trajectory sequence at the tail end of each mechanical arm by using a kinematics chain model, then the reference trajectory is used as a bottom layer distributed real-time control guide signal driven by an MAPPO algorithm, and comprehensive feedback is performed on task completion degree, motion smoothness and coordination in combination with a multi-layer reward function; and all the mechanical arm intelligent bodies are guided to cooperatively adjust joint actions in the tracking process, so that seamless connection of global planning and local control is achieved, and the smoothness and cooperative efficiency of carrying motion are remarkably improved.

The invention relates to a multi-stage optimization and kinematics constraint-based thumb posture estimation method and computing equipment. The method comprises the following steps of: acquiring original hand data, preprocessing the original hand data, and initializing parameters; constructing a multi-objective optimization function with multiple constraints, obtaining an initial estimation thumb posture based on the preprocessed data, taking the initial estimation thumb posture as an initial value, and performing recursive calculation by using a kinematics chain to obtain an accurate angle of each joint of the thumb; integrating the accurate thumb joint angle to complete hand posture parameters and outputting the parameters; a computing device is implemented based on the method. Complete and accurate thumb kinematic chain recovery under incomplete input is achieved, it is guaranteed that all estimated thumb joint angles conform to the human anatomy activity range, and high-fidelity basic data are provided for downstream application; the generated thumb motion sequence is continuous and smooth in the time dimension, and the visual experience in real-time interaction application is greatly improved; in an interactive application, a more natural, accurate and jitter-free gesture control experience can be realized.

The invention discloses a remote humanoid mapping control method based on a virtual reality motion capture mechanical arm. A motion data acquisition module transmits a matrix of a head coordinate system relative to a world coordinate system and a homogeneous transformation matrix to a coordinate system conversion module, establishes a base coordinate system and a tail end coordinate system, and establishes a kinematic chain conversion model; extreme position data of forearm extension of a user is collected, a proportionality coefficient is calculated, and a motion space boundary of the mechanical arm is output; pose normalization processing is carried out to form a discretized mechanical arm tail end pose sequence, and then the spatial relation between the mechanical arm sphere model and the obstacle is analyzed; generating a collision-free track by adopting a parallelization gradient optimization algorithm; the trajectory optimization module realizes trajectory smoothness and time optimization by constructing a multi-objective optimization function; and a mechanical arm motion simulation system is constructed, the tail end track precision is verified, and the controller drives the mechanical arm to achieve high-fidelity reproduction of user actions according to the track. According to the invention, high-precision and smooth-path motion migration of the mechanical arm is realized.

The multi-mode parallel robot comprises a base and a movable platform, and the movable platform is connected with the base through a first kinematic chain, a second kinematic chain and a third kinematic chain; the first kinematic chain comprises an eighteenth ball pair S18, a seventh connecting rod, a seventeenth sliding pair P17 and a first kinematic branch chain assembly which are connected in sequence, the first kinematic branch chain assembly is further connected with the base, and the eighteenth ball pair S18 is further connected with the movable platform. After the movement modes of the robot are changed, a certain movement range of two rotations and one movement is changed, the adaptability of the robot to different machining operations is improved, and the robot can be suitable for machining of a part with a larger dimension by changing the movement modes.

The disclosure regards a welding robot for performing welding operations when engaged by a positioning arm; the welding robot comprising, a robot arm configured for being connected to the positioning arm at a mounting point, a welding gun connected to the robot arm, wherein an at least first remote center of motion is defined by a point on a kinematic chain along the robot arm and the positioning arm. The welding robot is configured to continuously monitor the at least first remote center of motion and a tool center point of the welding gun during operation of the welding gun.

The invention discloses a four-axis compensation machining method under a workpiece offset clamping state, which comprises the following steps of: modeling a kinematic chain of a rotary table type four-axis machine tool to obtain a motion transformation equation between a coordinate axis of the four-axis machine tool and a cutter location under a workpiece non-offset clamping state; modeling a kinematic chain of the four-axis machine tool in the workpiece offset clamping state to obtain a general cutter spacing compensation calculation formula in the workpiece offset clamping state; and according to the obtained cutter spacing compensation calculation formula, a general numerical control machining program under the actual working condition is written. A cutter location source file generated by CAM software is processed, a numerical control machining program with a macro variable is obtained, and precise machining of a workpiece in an offset clamping state is achieved. Precise machining under the non-collinear state of the zero point of the workpiece and the rotary shaft of the rotary table can be achieved, the operation difficulty is lowered, the product clamping and aligning time is shortened, and the production efficiency is improved.

The invention discloses an isotropic completely-decoupled heavy-load three-movement parallel robot. The isotropic completely-decoupled heavy-load three-movement parallel robot comprises a fixed platform and a movable platform, a first kinematic chain, a second kinematic chain and a third kinematic chain are arranged between the fixed platform and the movable platform, and the fixed platform and the movable platform are connected through the first kinematic chain, the second kinematic chain and the third kinematic chain; the first kinematic chain comprises an eighth connecting rod assembly and a fifteenth connecting rod assembly; the device further comprises a first driving module shaped like a Chinese character'yi ', a second driving module shaped like a Chinese character'yi', a third module shaped like a Chinese character'yi ', a fourth module shaped like a Chinese character'yi', a fifth module shaped like a Chinese character'yi 'and a sixth module shaped like a Chinese character'yi'. The robot can be provided with a plurality of driving modules, the bearing capacity of the robot is improved to a certain extent on the basis of relatively simple control of a complete decoupling type robot, and the application range of the robot is enlarged. The invention further discloses a driving method of the isotropic completely-decoupled heavy-load three-movement parallel robot.

The invention belongs to the technical field of numerical control machine tool machining, and discloses a mirror image machining wall thickness error unified modeling method based on a spinor theory, which comprises the following steps: analyzing a mirror image machining constraint relationship, establishing a geometric constraint among cutter-wall thickness-support head, describing nominal motion and error motion of a motion axis of a mirror image machining system by using the spinor theory, and establishing a mirror image machining wall thickness error model. Based on a multi-body system theory and a spinor theory, a machining side kinematic chain unified model and a supporting side kinematic chain unified model of a mirror image machining system are established respectively, so that a nominal wall thickness kinematic unified model is established based on mirror image machining geometric constraints; the motion axis error matrix is introduced into a nominal wall thickness kinematics unified model to establish a mirror image machining actual wall thickness kinematics unified model, and the difference value between the actual wall thickness and the nominal wall thickness unified model is a mirror image machining wall thickness error unified model.

Disclosed is a threadable cycloid actuator having a cycloid drive with a through-bore tube, designed for the purpose of operatively connecting links in a kinematic chain and absorbing high torque and shock-load. The cycloid drive has a hollow input-shaft that receives a connective element at a joint in the kinematic chain, where the element traverses the through-bore tube and operatively connects to a further joint in the kinematic chain.

The invention relates to a biped robot gait planning method. The invention relates to the technical field of robot gait planning, and the method comprises the steps: taking a kinetic model of a robot as input, so as to achieve the neural network reasoning of simulation; describing the robot by using a URDF file, and enabling the robot to be equivalent to a kinematic chain formed by connecting rigid bodies in series; through accurate description, a robot consistent with that in reality is established in a simulation environment, the robot is enabled to carry out gait learning in a simulation physical environment, and supervised random divergence trial and error are carried out in a mode of setting initial conditions, termination conditions and reward and punishment conditions so as to realize gait learning. According to the invention, through repeated modification of parameters and structural adjustment of adaptability, a stable, low-energy-consumption and high-robustness control strategy is finally obtained through training.

Systems and methods for assisting movement of a user and / or a base connected to one or more robotic limbs are described herein. Forces may be applied to one or more robotic limbs to control movement of the base. The base may be attached to a user, or other payload, and forces applied to the base due to externally applied forces, such as those applied by a user interacting with an environment, may result in reactionary forces being applied to the one or more robotic limbs. These forces may be detected and used to determine one or more commands for operation of the one or more robotic limbs. Optionally, the robotic limbs may include one or more end effectors which may removably couple or otherwise be held substantially stationary relative to an environment to form a closed loop kinematic chain.

The application relates to the technical field of four-degree-of-freedom parallel mechanisms, in particular to a three-branch-chain space four-degree-of-freedom parallel mechanism which comprises a static platform, a mixed branch chain, a simple branch chain one, a simple branch chain two and a dynamic platform; the application has a mixed branch chain of a space sub-branch chain type and two simple branch chains, forms a basic motion chain containing three loops, thereby realizing the advantages of good rigidity and high precision, the displacement of the dynamic platform in the X-axis and Y-axis directions is controlled by two moving pairs respectively, the displacement in the Z-axis direction and the rotation around the Z-axis direction are controlled by four moving pairs, therefore, the application has good partial motion decoupling, the symbolic position direct solution is easy to obtain, thereby facilitating the motion control, trajectory planning and dynamics analysis of the parallel mechanism, and the three-dimensional position working space of the dynamic platform is large, the rotation capacity is strong, and the branch chains are not prone to interference.

The present invention discloses a planar two-degree-of-freedom mobile parallel robot with a zero-speed configuration for all joints. The robot comprises a base and a moving platform; a first kinematic chain and a second kinematic chain are disposed between the base and the moving platform; the first kinematic chain comprises a first-to-one mobile pair P111, an eighth link assembly, a first branch chain, and a second branch chain; the eighth link assembly is connected to the moving platform via the first-to-one mobile pair P111, and the first branch chain and the second branch chain are both connected to the eighth link assembly and the base; the second kinematic chain comprises a second-to-one mobile pair P211, a fifteenth link assembly, a third branch chain, and a fourth branch chain; the fifteenth link assembly is connected to the moving platform via the second-to-one mobile pair P211, and the third branch chain and the fourth branch chain are both connected to the fifteenth link assembly and the base. The robot can perform complex tasks. Also disclosed is a driving method for the planar two-degree-of-freedom mobile parallel robot with a zero-speed configuration for all joints.

Systems and methods for determining a user's health / wellness condition. Gait-based biometric data from a user is gathered using a sensor module. The biometric data is transmitted to a data processing module that compares characteristics of the biometric data with previously obtained baseline biometric data from the same user. Differences between the current data and the baseline data indicate changes in the user's condition. Databases containing kinematic chain models for the user are used to obtain more accurate and more specific indications regarding determined changes in the user's condition. A base kinematic chain model is created for the user when the user first uses the system and current kinematic chain models are generated for each biometric data set gathered. Characteristics of the base and the current kinematic chain models are compared to determine changes in the user's condition.

The invention belongs to the technical field of laser tool setting, and particularly relates to a method for calibrating a laser tool setting gauge by using a self-made standard rod. According to the method, the universal geometric parameter model is established for the self-made standard rod, so that the method can adapt to various different calibration scenes, and meanwhile, the equipment cost is reduced by more than 90%. In the calibration process, according to the trigger principle of the laser tool setting gauge, the installation error of the laser tool setting gauge is considered, a kinematic chain of the calibration system is constructed, and a mathematical model of the calibration process is further obtained. Through the mathematical model, the coordinate of the central point of the laser axis of the laser tool setting gauge in a machine tool coordinate system can be accurately solved. The problem that calibration is inaccurate due to installation errors of the laser tool setting gauge in the traditional calibration process is solved. In addition, the calibration cycle time of the method is greatly reduced, and the calibration efficiency is improved.

The invention discloses a single-degree-of-freedom N-weight reverse four-bar kinematic chain and a grabbing mechanism based on the kinematic chain, and belongs to the technical field of grabbing systems. The problems that in the prior art, a mechanism for stably grabbing long-length structures such as cables and pipelines lacks, and an existing grabbing mechanism is poor in stability and limited in enveloping range are solved. The device comprises a driving rod and N basic rod groups which are sequentially arranged end to end, the driving rod comprises two auxiliary rods, each basic rod group comprises a rod I and a rod II, and the rod I and the rod II are respectively provided with three auxiliary rods. And no degree-of-freedom redundancy exists, so that the system has better stability and controllability. And the N basic rod groups can continuously extend according to the connection mode. On the basis of keeping a reverse four-rod structure, the length of the kinematic chain can be gradually increased, and a larger enveloping range is realized.