A road strength instrument control system and its control method

Abstract

The present invention discloses a road strength meter control system and its control method, which includes a first actuator, a second actuator and a control mechanism; the first actuator includes a main controller, a servo motor, a servo motor driver, a first reduction gear set and a first connector, the second actuator includes a strong electricity controller, a three-phase motor, a second reduction gear set and a second connector, and the control mechanism includes a force sensor, a displacement sensor, a power supply and a control host; the present invention adds a set of servo drive system to the original system, and adopts two sets of drive systems to drive independently at different times. Especially in the processes of loading, holding and unloading, servo force closed-loop control is adopted, truly realizing the controllability and high control precision of the force loading process, and further improving the technical level of the product.

Description

Technical Field

[0001] This invention belongs to the field of path strength meter control technology, and particularly relates to a path strength meter control system and its control method. Background Technology

[0002] The comprehensive pavement material strength tester supports the operation and control of tests such as the Marshall test, the bearing ratio (CBR) test, and the unconfined compressive strength test. It is a dedicated device for realizing the specified test requirements for pavement material strength.

[0003] The control system of a traditional road strength meter uses a high-voltage control board to control a common three-phase motor to rotate at a constant speed and switch the direction of rotation to achieve uniform displacement control and the raising / lowering function of the crossbeam. The displacement rates involved in moving the crossbeam and the loading process are very different. The speed of moving the crossbeam is usually fast, reaching 50 mm / min, while the movement rate during the loading process after pressing the test block is very slow, usually set at 1-2 mm / min. The technical means used is to replace two sets of reduction mechanisms with different speed ratios to achieve positioning displacement control.

[0004] Obviously, the disadvantages of the above-mentioned traditional technical solutions are as follows: (1) The displacement rate control of the target loading sample is achieved by the combination of motor constant speed control and deceleration mechanism. This control is open-loop and cannot achieve closed-loop force control of the sample. Therefore, the force control of the sample loading process cannot be truly effective and controllable. It only achieves a partial force control effect by using open-loop control of displacement rate; (2) When different displacement control rates need to be switched, another deceleration mechanism needs to be replaced. The on-site test process is more complicated and the degree of automation is low; (3) It only has a digital display module and does not support network docking and data upload. The above-mentioned traditional conventional solution is the current main control system solution. The industry has also carried out technical innovations to address the disadvantage of needing to replace the deceleration mechanism in the test process. For example, some manufacturers have achieved the function of not needing to replace the deceleration mechanism by adding a set of ordinary three-phase motor and corresponding deceleration mechanism, which has improved the test efficiency accordingly. Summary of the Invention

[0005] This invention overcomes the shortcomings of the prior art by providing a path strength meter control system and its control method to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a path strength meter control system, comprising a first actuator, a second actuator, and a control mechanism; wherein:

[0007] The first actuator includes a main controller, a servo motor, a servo motor driver, a first reducer unit, and a first connector; the second actuator includes a high-voltage controller, a three-phase motor, a second reducer unit, and a second connector; and the control mechanism includes a force sensor, a displacement sensor, a power supply, and a control host.

[0008] The main controller is connected to the force sensor, displacement sensor, power supply, servo motor driver, high-voltage controller and control host. The main controller communicates with the control host through Ethernet or serial port. The main controller can synchronously measure and control force and displacement. The main controller can drive and control the servo motor. By driving and controlling the servo motor, the main controller can perform loading, holding and unloading of the force closed-loop control or displacement closed-loop control of the system.

[0009] The high-voltage controller is connected to the power supply, the three-phase motor and the main controller. The high-voltage controller receives control commands from the main controller and controls the speed of the three-phase motor by controlling the on and off of the relays to achieve open-loop displacement control of the system.

[0010] The control host is equipped with host computer control software, and the control host interacts with the main controller for data and control via Ethernet or serial port.

[0011] Both the main controller and the power controller are equipped with embedded software.

[0012] Preferably, the control host is an industrial control panel or a control computer, and the host computer control software in the control host can upload the acquired experimental data to a server via the network.

[0013] This invention also discloses a control method for a path strength meter control system, comprising the following steps:

[0014] S1. Initialization: The system powers on and performs a self-test. The embedded software of the main controller and the host computer control software are both initialized according to the predetermined design. After the host computer software connects to the main controller, it reads the parameters stored inside the main controller and verifies them with the parameters stored in the host computer software.

[0015] S2. Open-loop operation, lifting the crossbeam, the host computer software sends instructions to the main controller according to the predetermined design, and the main controller sends instructions to the power controller to complete the connection of the second connector and start the three-phase motor to run at a constant speed.

[0016] S3, Loading In: When the cylinder piston contacts the sample to be tested and the loading force reaches the inlet force, it automatically switches to closed-loop loading state. At this time, the host computer software sends a command to the main controller. The main controller controls the high-voltage controller to complete the actions of stopping the three-phase motor, separating the second connector, and connecting the first connector in sequence. Then the main controller drives the servo motor to perform closed-loop force control.

[0017] S4. Uniform loading or unloading: The main controller performs closed-loop PID control on the required force rate and the actual force rate. When the force value reaches the load holding target preset by the host computer software, it enters the load holding stage. The main controller performs closed-loop PID control on the required force value and the actual force value.

[0018] S5. End control. The host computer software sends instructions to the main controller according to the predetermined design. The main controller and the power controller sequentially complete the actions of stopping the servo motor, separating the first connector, and connecting the second connector. Then, the power controller drives the three-phase motor to retract the crossbeam.

[0019] S6. The embedded software of the main controller initiates Ethernet or serial communication data upload once every fixed time period Tp, and sends the data of force and displacement of the entire channel that has been saved according to the operation rules. The host computer software of the control host receives the data sent from the main controller in real time. The host computer software supports the import of various experimental projects, the generation of reports, the control of the experimental process, and the upload and management of experimental data.

[0020] Preferably, the processing algorithm steps of the embedded software of the main controller are as follows:

[0021] T1. Real-time acquisition of force sensor and displacement sensor values, and processing of the raw code values ​​of each channel force sensor by filtering algorithm, but no filtering processing of displacement sensor values;

[0022] T2. According to the operation instructions from the host computer, the three-phase motor and servo motor are operated and controlled separately. Specifically: for fast-moving operations such as moving the crossbeam, the main controller sends control instructions to the power controller, and in conjunction with the corresponding connector of the three-phase motor, the power controller operates the three-phase motor to achieve constant speed control to achieve the required moving speed. The running direction setting of the three-phase motor is controlled by the power controller. For slower control operations such as loading, holding and unloading, the main controller directly controls the drive servo motor to achieve closed-loop force control. At this time, it is required to disconnect the second connector corresponding to the three-phase motor and close the first connector corresponding to the servo motor.

[0023] T3. The main controller sends the experimental data collected in real time from each channel to the host computer for result display and process control. The host computer software is responsible for overall planning of the actions of each actuator, diagnostic processing, and safety protection processing.

[0024] Preferably, in step S6, the time period Tp can be optionally set to 20ms; the operation rules are: header + check code + system status + abnormal status + force channel value + displacement 0 channel value + displacement 1 channel value.

[0025] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0026] (1) The present invention adds a servo drive system to the original system and uses two drive systems to drive independently in a time-sharing manner. In particular, servo force closed-loop control is used in the loading, holding and unloading processes, which truly realizes the controllability and high control accuracy of the force loading process and further improves the technical level of the product.

[0027] (2) By using two sets of actuators, namely a servo motor + reducer and connector and a three-phase motor + reducer and connector, the test process was fully automated, and the test efficiency was greatly improved.

[0028] (3) It can be connected to industrial control screens or computers, supports network connection and test data upload, and meets the requirements of national quality inspection departments for the supervision of construction quality of engineering materials. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a connection diagram of a preferred embodiment of the present invention;

[0031] Figure 2 A schematic diagram of the control system modules of a preferred embodiment of the present invention;

[0032] Figure 3 This is a flowchart of the control system of a preferred embodiment of the present invention;

[0033] In the diagram: 1. Control host; 2. Servo motor driver; 3. Main controller; 4. Displacement sensor; 5. Servo motor; 6. Three-phase motor; 7. Force sensor; 8. High-voltage controller; 9. Gearbox. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Combination Figure 1 and Figure 2 As shown, a path strength meter control system includes a first actuator, a second actuator, and a control mechanism; wherein:

[0036] The first actuator includes a main controller 3, a servo motor 5, a servo motor driver 2, a first reducer unit, and a first connector. The second actuator includes a high-voltage controller 8, a three-phase motor 6, a second reducer unit, and a second connector. The control mechanism includes a force sensor 7, a displacement sensor 4, a power supply, and a control host 1. Both the first reducer unit and the second reducer unit belong to reducer unit 9.

[0037] The main controller 3 is connected to the force sensor 7, displacement sensor 4, power supply, servo motor driver 2, high-voltage controller 8, and control host 1. The main controller 3 communicates with the control host 1 via Ethernet or serial port. The main controller 3 can synchronously measure and control force and displacement. The main controller 3 can drive and control the servo motor 5. By driving and controlling the servo motor 5, the main controller 3 can perform loading, holding, and unloading of the system's force closed-loop control or displacement closed-loop control.

[0038] The high-voltage controller 8 is connected to the power supply, the three-phase motor 6 and the main controller 3. The high-voltage controller 8 receives the control commands from the main controller 3 and controls the speed of the three-phase motor 6 by controlling the on and off of the relays to realize the open-loop displacement control of the system.

[0039] The host computer 1 is equipped with host computer control software. The host computer 1 interacts with the main controller 3 for data and control via Ethernet or serial port.

[0040] Both the main controller 3 and the high-voltage controller 8 are equipped with embedded software.

[0041] Specifically, the control host 1 is an industrial control panel or a control computer, and the host computer control software in the control host 1 can upload the acquired experimental data to the server via the network.

[0042] like Figure 2 The control method of the path strength meter control system shown includes the following steps:

[0043] S1. Initialization: The system powers on and performs a self-test. The embedded software of the main controller 3 and the host computer control software are initialized according to the predetermined design. After the host computer software connects to the main controller 3, it reads the parameters stored inside the main controller 3 and verifies them with the parameters stored in the host computer software.

[0044] S2. Open-loop operation, lifting the crossbeam, the host computer software sends instructions to the main controller 3 according to the predetermined design, and the main controller 3 sends instructions to the power controller 8 to complete the connection of the second connector and start the three-phase motor 6 to run at a constant speed.

[0045] S3, Loading In: When the cylinder piston contacts the sample to be tested and the loading force reaches the inlet force, it automatically switches to closed-loop loading state. At this time, the host computer software sends a command to the main controller 3. The main controller 3 controls the high-voltage controller 8 to sequentially complete the actions of stopping the three-phase motor 6, separating the second connector, and connecting the first connector. Then, the main controller 3 drives the servo motor 5 to perform closed-loop force control.

[0046] S4. Uniform loading or unloading: The main controller 3 performs closed-loop PID control on the required force rate and the actual force rate. When the force value reaches the load holding target preset by the host computer software, the load holding stage begins, and the main controller 3 performs closed-loop PID control on the required force value and the actual force value.

[0047] S5. End control. The host computer software sends instructions to the main controller 3 according to the predetermined design. The main controller 3 and the power controller 8 sequentially complete the actions of stopping the servo motor 5, separating the first connector, and connecting the second connector. Then, the power controller 8 drives the three-phase motor 6 to retract the crossbeam.

[0048] S6. The embedded software of the main controller 3 initiates Ethernet or serial communication data upload once every fixed time period Tp, and sends the data of force and displacement of the entire channel that has been saved according to the operation rules; the host computer software of the control host 1 receives the data sent from the main controller 3 in real time. The host computer software supports the import of various experimental projects, the generation of reports, the control of the experimental process, and the upload and management of experimental data.

[0049] In this embodiment, the processing algorithm steps of the embedded software of the main controller 3 are as follows:

[0050] T1. Real-time acquisition of force sensor 7 and displacement sensor 4 values, and processing of the raw code values ​​of force sensor 7 acquired from each channel using a filtering algorithm, but not processing of the displacement sensor 4 values.

[0051] T2. According to the operation instructions from the host computer, the three-phase motor 6 and the servo motor 5 are operated and controlled respectively. Specifically: for fast-moving operations such as moving the crossbeam, the main controller 3 sends control instructions to the power controller 8, and in conjunction with the connector corresponding to the three-phase motor 6, the power controller 8 operates the three-phase motor 6 to achieve constant speed control to reach the required moving speed. The running direction setting of the three-phase motor 6 is controlled by the power controller 8. For slower control operations such as loading, holding, and unloading, the main controller 3 directly controls the drive of the servo motor 5 to achieve closed-loop force control. At this time, it is required to disconnect the second connector corresponding to the three-phase motor 6 and close the first connector corresponding to the servo motor 5.

[0052] T3 and main controller 3 send the experimental data collected in real time from each channel to the host computer for result display and process control. The host computer software is responsible for overall planning of the actions of each actuator, diagnostic processing, and safety protection processing.

[0053] Specifically, in step S6, the time period Tp can be optionally set to 20ms; the operation rules are: header + check code + system status + abnormal status + force channel value + displacement 0 channel value + displacement 1 channel value.

[0054] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0055] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A path strength meter control system, characterized in that, It includes a first executive body, a second executive body, and a control body; wherein: The first actuator includes a main controller, a servo motor, a servo motor driver, a first reducer unit, and a first connector; the second actuator includes a high-voltage controller, a three-phase motor, a second reducer unit, and a second connector; and the control mechanism includes a force sensor, a displacement sensor, a power supply, and a control host. The main controller is connected to the force sensor, displacement sensor, power supply, servo motor driver, high-voltage controller and control host. The main controller communicates with the control host through Ethernet or serial port. The main controller can synchronously measure and control force and displacement. The main controller can drive and control the servo motor. By driving and controlling the servo motor, the main controller can perform loading, holding and unloading of the force closed-loop control or displacement closed-loop control of the system. The high-voltage controller is connected to the power supply, the three-phase motor and the main controller. The high-voltage controller receives control commands from the main controller and controls the speed of the three-phase motor by controlling the on and off of the relays to achieve open-loop displacement control of the system. The control host is equipped with host computer control software, and the control host interacts with the main controller for data and control via Ethernet or serial port. Both the main controller and the power controller are equipped with embedded software.

2. The path strength meter control system according to claim 1, characterized in that, The control host is an industrial control panel or a control computer, and the host computer control software in the control host can upload the acquired experimental data to the server via the network.

3. A control method for a path strength meter control system, applied to a path strength meter control system as described in any one of claims 1-2, characterized in that, Includes the following steps: S1. Initialization: The system powers on and performs a self-test. The embedded software of the main controller and the host computer control software are both initialized according to the predetermined design. After the host computer software connects to the main controller, it reads the parameters stored inside the main controller and verifies them with the parameters stored in the host computer software. S2. Open-loop operation, lifting the crossbeam, the host computer software sends instructions to the main controller according to the predetermined design, and the main controller sends instructions to the power controller to complete the connection of the second connector and start the three-phase motor to run at a constant speed. S3, Loading In: When the cylinder piston contacts the sample to be tested and the loading force reaches the inlet force, it automatically switches to closed-loop loading state. At this time, the host computer software sends a command to the main controller. The main controller controls the high-voltage controller to complete the actions of stopping the three-phase motor, separating the second connector, and connecting the first connector in sequence. Then the main controller drives the servo motor to perform closed-loop force control. S4. Uniform loading or unloading: The main controller performs closed-loop PID control on the required force rate and the actual force rate. When the force value reaches the load holding target preset by the host computer software, it enters the load holding stage. The main controller performs closed-loop PID control on the required force value and the actual force value. S5. End control. The host computer software sends instructions to the main controller according to the predetermined design. The main controller and the power controller sequentially complete the actions of stopping the servo motor, separating the first connector, and connecting the second connector. Then, the power controller drives the three-phase motor to retract the crossbeam. S6. The embedded software of the main controller initiates Ethernet or serial communication data upload once every fixed time period Tp, and sends the data of force and displacement of the entire channel that has been saved according to the operation rules. The host computer software of the control host receives the data sent from the main controller in real time. The host computer software supports the import of various experimental projects, the generation of reports, the control of the experimental process, and the upload and management of experimental data.

4. The control method for a path strength meter control system according to claim 3, characterized in that, The processing algorithm steps of the main controller embedded software are as follows: T1. Real-time acquisition of force sensor and displacement sensor values, and processing of the raw code values ​​of each channel force sensor by filtering algorithm, but no filtering processing of displacement sensor values; T2. According to the operation instructions from the host computer, the three-phase motor and servo motor are operated and controlled separately. Specifically: for fast-moving operations such as moving the crossbeam, the main controller sends control instructions to the power controller, and in conjunction with the corresponding connector of the three-phase motor, the power controller operates the three-phase motor to achieve constant speed control to achieve the required moving speed. The running direction setting of the three-phase motor is controlled by the power controller. For slower control operations such as loading, holding and unloading, the main controller directly controls the drive servo motor to achieve closed-loop force control. At this time, it is required to disconnect the second connector corresponding to the three-phase motor and close the first connector corresponding to the servo motor. T3. The main controller sends the experimental data collected in real time from each channel to the host computer for result display and process control. The host computer software is responsible for overall planning of the actions of each actuator, diagnostic processing, and safety protection processing.

5. The control method for a path strength meter control system according to claim 3, characterized in that, In step S6, the time period Tp can be optionally set to 20ms; the operation rules are: header + check code + system status + abnormal status + force channel value + displacement 0 channel value + displacement 1 channel value.

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