1829 results about "Assembly systems" patented technology

The invention discloses a large model and knowledge graph linked multi-robot collaborative assembly system and method. The method comprises the following steps: acquiring data information of an assembly environment and an assembly task in real time through a sensing layer; preprocessing and deeply analyzing the data information through a data processing layer to obtain structured information; constructing a knowledge graph through a knowledge graph layer according to the structured information; task decomposition, distribution and optimization scheduling are carried out based on the knowledge graph through a task decision-making layer, and a task decision-making instruction is obtained; and controlling the corresponding robot to execute the allocated target assembly task through the execution layer based on the task decision instruction. Based on the structured expression ability of the knowledge graph, the multi-robot collaborative assembly system can better process the relation of complex tasks and optimize the task allocation process, realizes autonomous intelligent task decomposition and allocation, can improve the flexibility, response speed and collaborative efficiency of the system, and can be widely applied to the technical field of data processing.

The invention belongs to the technical field of automatic assembly, and discloses an automatic assembly system and method for a large nut of a water turbine ball valve, and the system comprises a mechanical arm, an end effector and an intelligent nut tightening control system. The end effector integrates an electromagnet adsorption mechanism, a servo drive rotating mechanism, a floating compensation mechanism and a visual recognition mechanism, nuts of different specifications are grabbed in a self-adaptive mode through an electromagnet, submillimeter-level accurate positioning is achieved through a laser galvanometer stereo camera, and the assembling posture is automatically adjusted in combination with the floating compensation mechanism. The intelligent control system adopts a staged tightening strategy, performs real-time monitoring through a torque sensor, and has a dual protection mechanism. The hydraulic turbine ball valve large nut assembling machine achieves full-automatic assembling of hydraulic turbine ball valve large nuts, has the advantages of being high in assembling efficiency, high in positioning precision, high in adaptability, reliable in quality and the like, solves the problems that manual assembling is large in labor intensity, many in potential safety hazards, poor in quality consistency and the like, and remarkably improves the assembling quality and efficiency of key parts of a hydropower station.

The invention relates to an automatic assembly system and method for multi-scale digital twin components, and the system comprises a semantic relationship construction module which is used for carrying out explicit definition on the structural features, functional attributes, spatial layout requirements and logic dependency relationships of the multi-scale components, and constructing semantic relationships among the three types of components; the semantic reasoning and constraint engine module is used for carrying out logical reasoning through the semantic relationship constructed by the semantic relationship construction module and judging whether the component combination meets the assembly constraint or not; the assembly generation and configuration module is used for generating an assembly topological structure and a connection sequence of a system shelf according to the component candidate set output by the semantic reasoning and constraint engine module; and the man-machine interaction and visualization module is used for supporting a feedback closed loop between the engineer and the system and providing a visual display interface. The problems that an assembly method depends on artificial experience and is difficult to support high-frequency and multi-scene production line reconstruction are solved, and the method has higher semantic interpretation capacity, automatic combination capacity and context adaptive capacity.

The invention relates to a pin injection molding part positioning and assembling system and a positioning method.The pin injection molding part positioning and assembling system comprises a workbench, the workbench is provided with a feeding mechanism, a first material moving mechanism, a first detection mechanism, a rotating mechanism, a vibration disc feeding mechanism, a second material moving mechanism and a second detection mechanism, and one side of the workbench is provided with a discharging mechanism; the rotating mechanism is located between the feeding mechanism and the vibration disc feeding mechanism, the first detection mechanism is located on one side of the first material moving mechanism, the second detection mechanism is located on one side of the second material moving mechanism, the discharging mechanism comprises a third multi-axis mechanical arm and a material taking and quick changing device, and the driving end of the third multi-axis mechanical arm is detachably connected with the material taking and quick changing device. And the third multi-axis mechanical arm drives the material taking and quick changing device to transfer the assembled products on the rotating mechanism. According to the positioning and assembling system for the contact pin injection molding part, automatic positioning is achieved, the positioning precision and efficiency are improved, and the overall productivity and quality are further improved.

The invention provides a control cabinet assembly system and assembly method, and relates to the field of control cabinet assembly, and the scheme is that the control cabinet assembly system comprises a control module and further comprises an identification module, the identification module is used for identifying a bar code on a control cabinet body, and the bar code comprises layout information of a control cabinet to be assembled; the display module is used for displaying the types and the numbers of the required electrical components, the fixing pieces and the connecting wires, and is also used for displaying the mounting positions of the corresponding electrical components; and the control module is electrically connected with the identification module and the display module, and the control module is used for storing and calling the corresponding assembly sequence, and is also used for controlling the display module to display the installation positions of the corresponding electrical components according to the assembly sequence of production. The assembling accuracy and the assembling efficiency of the control cabinet can be improved.

The invention relates to the technical field of automobile energy supply, in particular to a solid hydrogen storage-fuel cell integrated power assembly system based on dual-mode hydrogen supply, which comprises a hydrogen supply path identification module, a hydrogen storage unit state monitoring module, a linkage path switching module, a fuel cell load matching module and a safe hydrogen discharge regulation and control module. According to the method, the hydrogen supply pressure difference value is obtained by dynamically comparing the pressure of the cavity of the hydrogen storage tank with the pressure of the hydrogen inlet of the fuel cell, the current hydrogen supply path state can be accurately recognized in the early stage, rapid judgment of the hydrogen supply mode and accurate control of path switching are achieved, whether the risk of hydrogen supply interruption exists or not can be effectively screened, and the reliability of hydrogen supply is improved. The switching reliability of a hydrogen supply channel is improved through cross comparison of key state signals of a main channel and a standby channel, and instant response and energy consumption optimization of hydrogen discharge safety regulation and control are guaranteed through a linkage feedback mechanism between the hydrogen concentration change rate in unit time and catalytic converter control power.

The invention provides a display screen assembly system, method and device and a storage medium, the system comprises a data management analysis module, a multi-agent module, an implementation monitoring module and a communication module which are in communication connection with each other, the data management analysis module is configured in a training framework and is responsible for processing and generating a process database related to display screen assembly, and the multi-agent module is configured in a training framework; intelligent process planning and optimization suggestions are provided; the multi-agent module is configured for assembly process management and comprises a plurality of agents, and each agent is responsible for different assembly tasks and carries out coordination and information sharing through the communication module; the implementation monitoring module is configured on a production site, integrates various sensors, and collects key data in the assembly process in real time. And the communication module is configured to manage communication and information transmission among the intelligent agents. According to the method, by introducing the large language model and the multi-agent module, higher-level intelligent process planning and optimization are realized, so that the assembly process is more efficient and flexible, and the adaptability is higher.

A stowable tailgate step assembly system comprises a frame with two interconnected frame arms adapted to be mounted longitudinally in a vehicle tailgate. A slide module, releasably latched to the frame, comprises two longitudinal carrier arms which translate in relation to the frame arms, and a step assembly. The step assembly comprises two slide arms which translate in relation to the carrier arms, and a first step and at least one additional step pivotally connected by at least one link rod to facilitate synchronous rotation of the steps. Control means to control rotation of the steps during translation of the carrier arms from a stowed position to an extended position are provided. Deployment means to control rotation of the steps between the extended position and a deployed position are also provided. A lock-out latch rotationally connected to at least one carrier arm engages at least one associated frame arm to prevent translation of the carrier arm in relation to the associated frame arm when the step assembly is in the extended position.

A construction section for supporting a glass panel and configured to be coupled to a building structure. The construction section may comprise a wood mullion, an upper fitting, and a gravity fitting. The wood mullion may comprise an elongate body, a pair of cutouts in the upper and lower ends, and upper and lower pockets. The elongate body may comprise an exterior face, an upper end, and a lower end. The pair of cutouts in the upper and lower ends may be configured to receive at least a portion of the building structure. The upper and lower pockets may comprise a void area within the elongate body adjacent the exterior face. The upper fitting may be configured to support at least a portion of the glass panel. The gravity fitting may be coupled within the lower pocket and configured to support at least a portion of the glass panel.

The invention belongs to the technical field of droppers, and particularly relates to an intelligent pre-assembling platform and a pre-assembling method for an integral dropper of a contact network, and the intelligent pre-assembling platform comprises an automatic feeding system, an automatic laser etching system, a mechanical arm flexible assembling system, a tension / length detection system, a crimping process detection system, a bundling and labeling system, a rack, an auxiliary device and a quick-changing device, the dropper wire feeding system comprises a wire feeding wheel, a wire winding device, a straightening device, a fusing device and a servo length control device; the mechanical arm flexible assembly system comprises a six-axis mechanical arm and a crimping quick-change device; the auxiliary device comprises a secondary positioning mechanism, a heart-shaped ring / crimping pipe spacing control mechanism and a transfer printing device; the quick-change device is composed of a hydraulic cylinder, a crimping die and a quick-change transition block. According to the invention, the pre-assembling time of a single dropper is shortened, the dropper assembling process is shortened, the dropper pre-assembling device is suitable for dropper pre-assembling with different specification requirements, a crimping die is convenient to replace, meanwhile, personnel distinguishing is convenient, and finished products are not damaged in the bundling process.

The invention relates to the technical field of electromagnetic compatibility conducted immunity testing, and discloses an electromagnetic compatibility conducted immunity calibration system and method, and the system comprises a signal generation module, a coupling and decoupling network adaptive assembly system, a calibration load access system, an auxiliary equipment terminating system, and a grounding protection system. The method can adapt to different types of coupling and decoupling networks, normalizes the calibration process, reduces the calibration uncertainty, and reduces the introduced uncertainty by 17.9% compared with a conventional method. The invention further discloses an automatic calibration method, the calibration process of conduction immunity is optimized, the initial level can be set through an algorithm, the target level addressing time can be reduced, the calibration time can be shortened, the effective detection time proportion can be improved, and various parameters of an actually measured product are embedded in all links of the calibration process, so that the calibration accuracy is improved. The device can better simulate the testing process of an actually measured product, and improves the calibration accuracy and applicability.

The invention relates to the technical field of mechanical arms, and discloses a self-adaptive rapid assembly system and method for a laser radar, and the system comprises an acquisition module, a mechanical arm is provided with a clamping claw and a welding head; the control module is electrically connected with the acquisition module and the mechanical arm, and the control module comprises an acquisition unit which controls the mechanical arm to place a shell on a working plane and controls the mechanical arm to press a crimping stud into a crimping hole site; the judgment unit collects the image of the crimped shell to judge whether the plane is flush or not; when it is judged that the plane is flush, the processing unit controls the mechanical arm to clamp the mainboard module, and the crimping stud penetrates through a mounting hole position of the mainboard module; determining the amount of soldering tin, and controlling the welding head to fix the mainboard module; the adjusting unit collects image data of the welding position to judge whether welding defects exist or not, and when the defects exist, the welding head is controlled to conduct repair welding. Through the acquisition module, the mechanical arm and the control module, automation of laser radar assembly is realized, and the assembly precision is improved.

Systems, devices, and methods for performing minimally invasive spinal procedures are described herein. The systems, devices, and methods may be used to percutaneously access the spinal canal and perform a spinal procedure in multiple locations along the canal, e.g., bilaterally and / or at multiple levels from a single access point. The systems and devices may integrate various instruments for performing the procedures, thus improving their ease of use, reducing procedural complexity, and minimizing procedure time.

The application discloses a transfer box for precise positioning long rod, and relates to the technical field of transfer equipment, and aims to solve the technical problems that the existing loading and unloading box can fix the rod body, lacks reinforcement and protection for rod bodies with different length and width sizes, the rod body is easily damaged by bumping and impact during transportation, and the loading and unloading is complicated, and the intelligent degree of the mechanical arm is high, and the application comprises a box body mechanism and a protection mechanism, and the inner wall of the box body mechanism is connected with the protection mechanism. The application can complete the installation of the long rod through simple pushing and pulling steps, and after the installation is completed, the device can automatically adapt to the height of the long rod, so that the collision during transportation hardly affects the position of the long rod, the sliding of the long rod in the device is avoided, the protection effect of the device on the long rod is improved, meanwhile, the simple installation steps reduce the demand for the corresponding equipment when the device is used, and the operation difficulty and cost of the entire assembly system are reduced.

The invention discloses a tab welding mechanism and a battery assembly system.The tab welding mechanism comprises a base, a supporting base, a tab pressing structure and a welding assembly, and the supporting base is arranged on the base and used for supporting and fixing a core body of a battery cell; the tab pressing structure is arranged on the base table and is configured to move towards the supporting seat so as to be used for pressing and collecting a plurality of tab pieces stacked on the battery cell; the welding assembly is arranged on the base table and is configured to move towards the supporting base so as to weld the multiple folded electrode lug pieces to form the electrode lug part. By means of the mode, the problem that the pole lug welding technology is high in difficulty can be solved, and the yield of batteries is increased.

The invention discloses an assembly system and assembly equipment for an engineering machinery supporting leg assembly. The assembly system comprises an underframe assembly placing device, a lifting device and a lifting device, the supporting leg combining device comprises a position adjusting module, a pushing mechanism and a clamping and centering mechanism, the clamping and centering mechanism is used for clamping the supporting leg and enabling the central axis of the supporting leg to coincide with the central axis of the clamping space, and the pushing mechanism is arranged at the end, away from the chassis assembly placing device, of the clamping and centering mechanism and used for pushing the supporting leg into the supporting leg mounting cavity; the position adjusting module is movably arranged below the clamping and centering mechanism and the pushing mechanism and is used for adjusting the spatial position of the supporting leg; the image acquisition device is used for acquiring a placement image set of the underframe assembly; the control system is used for controlling the position adjusting module to execute position adjusting operation according to the placed image set so that the central axis of the supporting leg can coincide with the actual installation axis of the supporting leg installation cavity, and the assembling efficiency and the assembling quality of the supporting leg assembly can be improved.

The invention provides an adsorption clamping mechanism for assembling an automobile water tank pressure cap and an assembling system, and the adsorption clamping mechanism is characterized by comprising a rubber pad assembling support frame; the three-axis moving unit is used for moving along the x axis, the y axis and the z axis; an adsorption clamping unit; the rubber pad assembling control unit is used for controlling operation of the three-axis moving unit and the adsorption clamping unit so that assembling of the rubber pad can be achieved, and the adsorption clamping unit comprises a fixing frame connected with the three-axis moving unit; the rubber pad adsorption assembly is arranged on one side of the fixing frame and used for adsorbing a rubber pad; the shell clamping jaw is arranged on the other side of the fixing frame and used for clamping the shell; the shell sensor is arranged on one side of the shell clamping jaw and used for detecting whether a shell exists or not, and the rubber pad adsorption assembly comprises a vacuum generator and used for generating suction force and detecting whether a rubber pad is adsorbed or not according to the size of the suction force. In conclusion, the mechanism and the system can achieve efficient and accurate rubber pad adsorption and shell clamping.

The invention belongs to the technical field of wire harness assembly, and discloses a flexible wire harness intelligent assembly system and a control method thereof. Comprising the following steps: reading basic information data of an automobile wire harness raw material; according to the read basic information data of the automobile wire harness raw material, selecting a matched wire, and carrying out interception and terminal crimping on the wire to obtain an initial automobile wire harness; detecting the terminal crimping position, judging whether the terminal crimping position of the initial automobile wire harness is qualified or not, detecting the terminal angle, and judging whether the terminal angle of the initial automobile wire harness is qualified or not; electrical detection is conducted on the initial automobile wire harness with the qualified terminal crimping position and terminal angle, whether electrical conduction of the initial automobile wire harness is normal or not is judged, if the electrical conduction of the initial automobile wire harness is normal, assembly of the initial automobile wire harness is qualified, and if the electrical conduction of the initial automobile wire harness is abnormal, assembly of the initial automobile wire harness is unqualified. And potential safety hazards caused by unqualified assembly are reduced.

The invention relates to the technical field of stair construction, and discloses a stair socket reinforcing formwork construction process which comprises the following steps of preparation before construction, completion of technical disclosure, assembly inspection and site arrangement. The installation of the modularized reinforcing assembly comprises the steps of arranging, fixing and calibrating an inclined strut assembly, a horizontal pull rod assembly and a quick connecting node; a formwork is installed and reinforced, the bottom formwork and the side formwork are connected through a horizontal pull rod, and the side formwork is supported through an inclined strut assembly; and the embedded reinforcing assembly is embedded, specifically, the embedded reinforcing assembly is arranged in the formwork and fixed to the formwork. By adopting the modular reinforcing assembly system and through standardized design and dynamic adjustment functions of the inclined strut assemblies, the horizontal pull rod assemblies and the rapid connecting joints, rapid arrangement, flexible adjustment and efficient installation in the construction process are achieved. Compared with a traditional formwork erecting process depending on manual measurement and field processing in the prior art.

The embodiment of the utility model provides a pressing assembly and an assembling system, and the pressing assembly comprises a stop block structure which is provided with a limiting groove matched with an electrode piece; the pressing block structure is connected with the stop block structure, and at least one end of the pressing block structure is provided with a sheet pressing piece corresponding to the limiting groove; wherein the pressing block structure is located at the first position, the stop block structure is located in the ammeter battery box, the sheet pressing piece abuts against the electrode piece, the pressing block structure moves towards the ammeter battery box to the second position, and part of the electrode piece is located in the installation groove. According to the technical scheme of the utility model, the stop block structure and the pressing block structure are utilized to realize the limiting and stable installation of the electrode piece, so that the whole assembly process is more reliable.

A vehicle assembly system for sealing and skiving vehicle seams. The assembly system includes an upstream seam sealant station that determines offsets between vehicle reference points and the seams using a vision sensors and sends the offsets to a downstream seam skiving station. The assembly system also measures the size of the sealant bead and controls the sealant dispense pressure to maintain the desired size.

The invention provides a rapid assembly system and method for in-cabin parts of cylindrical products, and the system is characterized in that a mechanical arm is fixedly mounted through a base, the tail end of the mechanical arm is sequentially provided with a six-dimensional force sensor and a tail end execution device, and the tail end execution device is used for grabbing the to-be-assembled parts and carrying the to-be-assembled parts to a mounting position in a cylindrical section along a preset path; the six-dimensional force sensor is used for acquiring contact force and torque on a tail end load and an assembly path so as to judge the state of the assembly path; the assembly platform is used for supporting and flexibly clamping a cylinder section product, the light source equipment and the binocular vision camera form an image acquisition system, and the binocular vision camera is used for acquiring pose and mark point coordinate information of a cylinder section. According to the method, the problems that during existing automatic assembly, multi-batch and multi-state real-time posture positioning is tedious, coaxial assembly of components in a barrel-section-shaped product cabin is difficult to guarantee, and extrusion collision damage is caused in the assembly process are solved, the operation difficulty and risk are reduced, and the system assembly flexibility is improved.

Guides, systems, and methods for maintaining, correcting and / or fusing joint deformities are disclosed. The guide system including a cut guide, an alignment guide, and at least one directional wire. The cut guide including a base portion, an extension member extending away from a bottom surface of the base portion, and at least one arm extending away from an end of the base portion. The alignment guide, including a base portion, a first extension member extending away from a bottom surface of the base portion in a first direction, and a second extension member extending away from the bottom surface of the base portion in a second direction. Methods of using a guide system for maintaining, correcting and / or fusing joint deformities are also disclosed.

The invention provides a single battery end cover welding device, an assembling method and a single battery, the single battery comprises a shell and an end cover, the end cover is arranged at one end of the shell, and a first connecting seam and a second connecting seam which are arranged in the circumferential direction of the shell are formed in the connecting position of the shell and the end cover; the end cover welding device comprises a material conveying assembly and a welding assembly. The material conveying assembly comprises a material conveying line, a first clamp and a second clamp, and the first clamp and the second clamp are arranged on the same material conveying line in a spaced mode. The first clamp is used for fixing the shell and making the first connecting seam visible; the second clamp is used for fixing the shell and making the second connecting seam visible; the welding assembly is arranged along the material conveying line and used for welding the first connecting seam when the first clamp fixed with the single battery is conveyed to the welding assembly and welding the second connecting seam when the second clamp fixed with the single battery is conveyed to the welding assembly.

The invention provides an error modeling method and system based on a CCD camera alignment assembly system, and relates to the technical field of high-precision electronic manufacturing assembly, and the method comprises the steps: obtaining internal parameters and external parameters of a CCD camera through calibration, building a camera and mechanical coordinate system conversion relation, and constructing a collaborative calibration error tree; controlling the motion platform to move, synchronously acquiring pose and environment temperature data, decomposing vibration and thermal deformation error components through time-frequency analysis, and superposing the vibration and thermal deformation error components into dynamic errors; extracting a positioning error based on the pose data, and constructing a mechanical-optical coupling error spectrum in combination with the distortion parameters; and finally, fusing the collaborative calibration error tree, the dynamic error and the coupling error atlas to generate a global error atlas, and completing alignment assembly system error modeling based on the CCD camera. According to the invention, the precision and applicability of error modeling are improved.

The invention discloses a shield tunnel segment digital splicing method, which comprises the following steps: step 1, generating segment point cloud data: performing reverse scanning on a single segment through a laser scanning system in a shield tunneling machine until the scanning of the whole-ring segment of a tunnel is completed, and generating the segment point cloud data; step 2, obtaining an optimal relative position between segments: importing the segment point cloud data into a virtual assembling platform, establishing a segment three-dimensional model, planning a segment assembling path in the virtual assembling platform, and then performing segment virtual assembling according to the segment assembling path to obtain the optimal relative position between the segments; 3, calculating a theoretical rotation angle: calculating the theoretical rotation angle of the central line of the segment relative to the vertical center of the circle center when the segment is at the optimal relative position; step 4, calculating a position deviation and an offset angle; and sixthly, the pipe pieces are assembled. According to the method, a complete and efficient digital splicing system is established, and the overall level of shield tunnel construction is improved.

The AUTOBUILD schedule system / module gathers project design data information and basic schedule constraint goal information and separates and categorizes all parts and pieces from large pieces of equipment and assembly systems to the smallest connection materials such as closure trim, screws, nails, adhesives etc. From a basic construction logic, the AUTOBUILD schedule system / module assembles the initial schedule for the project. This initial schedule is then reevaluated by its internal system taking into several factors, including (1) an initial review and resequencing from a human professional; (2) information received from vendors bidding the project; and (3) input giving further accurate details of quantities required, actual production and delivery dates, weather, and / or other environmental factors, etc. The AUTOBUILD schedule system / module then tracks the actual project progress utilizing information and status of contractual commitments, procurement approvals, fabrication, and delivery.

The utility model discloses a finished steel plate and equipment belt assembly type system installation structure which comprises a keel system, an integrated equipment belt and a hanging piece system. The keel system comprises hanging bars, hanging pieces connected with the hanging bars and main keels installed on the hanging pieces. The integrated equipment belt comprises a metal cover, an air opening shutter installed in the metal cover and a light-transmitting piece. The hanging piece system comprises a fixing piece, a special keel and a closing-up strip, the fixing piece is hung on the main keel, the upper end of the special keel is connected with the fixing piece, the lower end of the special keel is connected with the closing-up strip, a hanging groove is formed in the upper end of the closing-up strip, a hanging piece is installed on the outer side face of the metal cover, and the hanging piece is hung on the hanging groove. The mounting structure has the advantages of being simple to mount, attractive in decoration, detachable to assemble and good in appearance quality.

The invention relates to a dual-motor drive assembly system which comprises a power output source, and an input unit is oppositely arranged on the power output source so as to be connected with a speed reduction unit. The speed reduction unit transmits the torque to the low-speed driving gear; a first compound gear shaft is arranged at the output end of the low-speed driving gear, the first compound gear shaft and the low-speed driving gear are in meshing transmission with a second compound gear shaft, the second compound gear shaft comprises two gears different in modulus, and the output shaft gear is arranged at the output end of the second compound gear shaft. And the output shaft gear is meshed with the pinion of the first compound gear shaft to finish torque output so as to meet the requirements of the whole vehicle. By using the two intermediate shafts, the gearbox can more effectively distribute power from different motors, energy loss is reduced, and transmission efficiency is improved. And due to the multi-gear design, the mine car can keep the optimal performance under different loads and speeds.

The invention relates to a speed reducer assembly system and method, and belongs to the technical field of intelligent assemblation.The method comprises the steps that multi-dimensional performance data of a speed reducer are collected; the pre-constructed intelligent assembly model calculates assembly evaluation indexes and / or an average value of the assembly evaluation indexes based on the multi-dimensional performance data; the intelligent assembly model judges whether the assembly is qualified or not based on a comparison result of an average value of the assembly evaluation indexes and a preset target value score; wherein a comprehensive performance evaluation function model based on weight distribution is arranged in the intelligent assembly model so as to calculate the assembly evaluation indexes and / or the average value of the assembly evaluation indexes. According to the intelligent assembly model provided by the invention, the dependence on manual judgment is reduced, and the automatic evaluation of the overall performance of the speed reducer is realized. The method provides a basis for quantitative evaluation for different application scenes, and solves the problem that a traditional test means cannot provide comprehensive performance evaluation.