A kind of truss mechanical hand mechanism for programmable controller system application practical training examination

Abstract

The present application belongs to the technical field of programmable controller (PLC) system application practical training examination, especially a truss mechanical hand mechanism for programmable controller system application practical training examination, comprising a truss main body; a pneumatic sliding table installed on the truss main body; a telescopic air cylinder installed on the pneumatic sliding table; a pneumatic clamping jaw connected with the output end of the telescopic air cylinder; a control unit connected with the programmable controller PLC signal; a plurality of thin film pressure sensors uniformly integrated on the clamping surface of the pneumatic clamping jaw; a position sensor for detecting the position of the telescopic air cylinder and the pneumatic sliding table; a gas pressure sensor arranged in the pneumatic circuit of the telescopic air cylinder and / or the pneumatic clamping jaw; and a signal prompting device installed at a conspicuous position of the truss main body. In the present application, through the integration of the thin film pressure sensor, the position sensor and the gas pressure sensor, real-time quantitative monitoring of the clamping state, carrying precision and gas source stability is realized, thereby providing a data basis for objective examination.

Description

Technical Field

[0001] This invention relates to the field of application training and assessment technology for programmable logic controller (PLC) systems, and in particular to a gantry robot mechanism for application training and assessment of programmable logic controller systems. Background Technology

[0002] In practical training and assessment of industrial automation and PLC teaching, gantry robots are often used as the core execution unit to simulate material handling processes. Students write PLC programs to control the robot's cylinders, grippers, and slides to complete the tasks of gripping and moving parts.

[0003] However, most existing training devices are based on limited functions and only have simple open-loop control capabilities, exhibiting the following significant shortcomings:

[0004] Lack of intelligent sensing: It is impossible to detect in real time whether the material is reliably clamped, whether the clamping force is appropriate, and whether the handling position is accurate, resulting in grasping failure or high handling error rate, and the assessment results rely on subjective judgment.

[0005] Lack of adaptive capability: The control parameters are fixed and cannot dynamically adjust the clamping force or conveying path according to the material state (such as slight slippage or positional deviation), which reduces the realism of the training and the teaching value.

[0006] Lack of fault diagnosis: When there are fluctuations in gas source pressure, mechanical blockage, or sensor failure, the system cannot provide early warnings, which not only poses a safety hazard but also hinders the training of trainees' ability to troubleshoot.

[0007] Data traceability is difficult: the operation process lacks quantitative records, making it impossible to accurately review and objectively score the trainees' operation process and adjustment decisions;

[0008] Therefore, there is an urgent need for a gantry robot mechanism that integrates intelligent sensing, adaptive control, and data traceability functions to improve the intelligence level, safety, and teaching effectiveness of practical training and assessment. Summary of the Invention

[0009] Based on the technical problems existing in the prior art, this invention proposes a gantry robot mechanism for practical training and assessment of programmable controller systems.

[0010] This invention proposes a gantry robot mechanism for practical training and assessment of programmable logic controller (PLC) systems, comprising:

[0011] The truss body, in conjunction with the pneumatic slide, provides precise linear guidance for the horizontal movement of the robot, constrains the degrees of freedom in other directions, and ensures the straightness of the transport path and the repeatability of the positioning accuracy.

[0012] A pneumatic slide, mounted on the truss body, is used to drive the telescopic cylinder and the pneumatic gripper to move horizontally;

[0013] A telescopic cylinder is mounted on the pneumatic slide.

[0014] A pneumatic gripper is connected to the output end of the telescopic cylinder;

[0015] The control unit is connected to the programmable logic controller (PLC) via signals.

[0016] Multiple thin-film pressure sensors are uniformly integrated on the clamping surface of the pneumatic gripper; real-time pressure data of the clamping surface is collected to provide feedback for precise control of the clamping force, avoiding workpieces from falling off due to excessive looseness or being damaged due to excessive tightness, and adapting to the clamping needs of workpieces of different materials in practical training.

[0017] A position sensor is used to detect the position of the telescopic cylinder and the pneumatic slide; it accurately feeds back the telescopic position of the cylinder and the horizontal position of the slide, providing a basis for the control unit to control the position closed loop, ensuring the accuracy of the robot's motion positioning, and meeting the evaluation criteria for positioning accuracy in practical training assessments.

[0018] A pneumatic pressure sensor is installed in the pneumatic circuit of the telescopic cylinder and / or pneumatic gripper to monitor the real-time pneumatic pressure, determine whether the working status of the pneumatic system is normal, avoid problems such as insufficient clamping force and failure of telescopic action due to abnormal air pressure, and ensure the stability and safety of the training process.

[0019] The signal indication device is installed in a conspicuous position on the main body of the truss; it provides feedback on the system status (such as normal operation, abnormal alarm, adjustment execution) through intuitive means such as sound and light, so that the training operators can observe the equipment status in real time and the examiners can judge the execution effect of the control logic.

[0020] The control unit is configured to perform the following operations:

[0021] System initialization and calibration: Establish a unified coordinate reference and perform no-load and load calibration on all sensors. Preset threshold parameters including minimum effective clamping force threshold Fmin, maximum safe clamping force threshold Fmax, position tolerance Ptol, normal air pressure range [Pmin, Pmax], minimum dwell time Tstay, and safe clearing time Tclear.

[0022] Real-time data acquisition: Data from each sensor is acquired synchronously over a control cycle Ts, including clamping force estimation F^, current position (x,y,z), and current air pressure value Pair;

[0023] State determination: Based on the collected data, the clamping deviation Df, position deviation Dp and air pressure deviation Da are calculated and weighted to obtain the comprehensive state coefficient Q=αDf+βDp+γDa, where α,β,γ are preset weight coefficients;

[0024] Adaptive control decision: When the comprehensive state coefficient Q continuously exceeds the preset threshold H and reaches the shortest dwell time Tstay, a control command including adjustment direction and adjustment step size Δs is generated, and the signal prompting device is driven to provide a prompt.

[0025] Reset and Recording: After adjustment is completed or the safe clearing conditions are met, the reset procedure is executed, and the relevant data of this event is recorded to non-volatile memory.

[0026] In a preferred embodiment, the clamping surface of the pneumatic gripper is made of a flexible material, and the thin-film pressure sensor is evenly distributed around the circumference of the clamping surface and configured to simultaneously detect normal pressure and tangential shear force. The flexible clamping surface can avoid damage to fragile or easily scratched workpieces and is suitable for clamping scenarios of workpieces of various materials in training. The evenly distributed circumference of the sensor and the multi-directional force detection improve the comprehensiveness of the clamping force distribution detection, effectively identify risks such as workpiece clamping offset and slippage, and further improve the accuracy and reliability of clamping control.

[0027] In a preferred embodiment, the control unit includes a non-volatile memory for storing calibration data, threshold parameters, and event records; this enables long-term stable storage of core data, ensuring that calibration parameters and historical event records are not lost even when power is off, guaranteeing rapid recovery of operation after system restart, facilitating the retrieval of historical data for analysis and review during practical training, and providing examiners with complete traceability of the operation process.

[0028] Compared with the prior art, the present invention provides a gantry robot mechanism for practical training and assessment of programmable controller systems, which has the following beneficial effects:

[0029] 1. Intelligent sensing and quantitative evaluation: By integrating thin-film pressure sensors, position sensors and air pressure sensors, real-time quantitative monitoring of clamping status, handling accuracy and air source stability is achieved, providing a data foundation for objective assessment.

[0030] 2. Adaptive Control and Precise Guidance: Based on an algorithm-driven comprehensive state coefficient determination and dwell mechanism, interference is effectively filtered out, and adjustment commands are issued only when truly needed. Intuitive prompts for adjusting direction and step size via indicator lights guide trainees to operate precisely, improving teaching efficiency.

[0031] 3. Fault diagnosis and safety enhancement: The built-in sensor health monitoring and air pressure anomaly diagnosis functions can promptly alarm and enter conservative operation mode when problems occur, which significantly improves the safety of the training process.

[0032] 4. Data traceability and teaching review: The key data recording function throughout the process allows for the complete reproduction of students' operation procedures, system responses, and adjustment effects, facilitating accurate teaching and scoring by teachers, and also providing a basis for optimizing control parameters. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of a gantry manipulator mechanism for practical training and assessment of programmable controller systems proposed in this invention.

[0034] Figure 2 This is a schematic diagram of the installation structure between the pneumatic gripper and the pneumatic slide of a gantry manipulator mechanism for practical training and assessment of programmable controller systems proposed in this invention.

[0035] Figure 3 This invention presents a control flowchart for a gantry robot mechanism used in practical training and assessment of programmable logic controller (PLC) systems.

[0036] In the diagram: 1. Truss main body; 2. Telescopic cylinder; 3. Pneumatic gripper; 4. Pneumatic slide; 5. Signal prompting device. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0038] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0039] Example 1, referring to Figures 1-2 A gantry robot mechanism for practical training and assessment of programmable logic controller (PLC) system applications, comprising:

[0040] The truss body 1, made of aluminum profile or steel structure, works in conjunction with the pneumatic slide 4 to provide precise linear guidance for the horizontal movement of the robot, constrain the degrees of freedom in other directions, and ensure the straightness and repeatability of the transport path.

[0041] The pneumatic slide 4 is mounted on the truss body 1 and is used to drive the entire gripping mechanism to move horizontally;

[0042] The telescopic cylinder 2 is mounted on the pneumatic slide table 4 via a bracket;

[0043] The pneumatic gripper 3 is connected to the output end of the telescopic cylinder 2, and several thin-film pressure sensors are integrated on its gripping surface.

[0044] The control unit (which can be integrated into the PLC or used as a standalone module) connects to all sensors and actuators;

[0045] The signal indicator 5 (such as an LED tri-color light) is installed in a conspicuous place on the truss body 1;

[0046] The pressure sensor is installed in the pneumatic circuit;

[0047] G-shaped locking groove 9 is located at the bottom of the truss and is used to quickly clamp and fix the mechanism to the edge of the training platform or the profile beam in conjunction with the pressure plate or wedge;

[0048] The gripping surface of the pneumatic gripper 3 is preferably made of flexible materials such as polyurethane to increase friction and protect the material; thin-film pressure sensors are evenly distributed around the circumference of the gripping surface to comprehensively sense the force; the control unit has a digital I / O interface, which is compatible with the training PLC, making it easy for students to wire and program.

[0049] Example 2, refer to Figure 3 A gantry manipulator mechanism for practical training and assessment of programmable logic controller (PLC) systems, whose core intelligence lies in a series of operational processes executed by the control unit, as follows:

[0050] 1. System initialization and calibration

[0051] After the control unit is powered on, a unified geometric and coordinate reference is first established, with the installation base point of the gantry robot as the origin of the world coordinate system. Then, the thin-film pressure sensor integrated on the pneumatic gripper is calibrated.

[0052] No-load calibration: Collect raw data from each sensor under no-material conditions, and calculate the zero-point offset bk and noise scale σk;

[0053] Load calibration: Apply a known normal force, calculate the conversion factor Cf, and establish a measurement chain from electrical readings to physical force values; preset threshold parameters are loaded and stored in non-volatile memory.

[0054] 2. Real-time data acquisition and processing

[0055] The control unit synchronously acquires all sensor data at a control cycle Ts (preferably 5-10ms) and preprocesses it. For the clamping force, the effective weight of each sensor is calculated.

[0056]

[0057] The clip function restricts the value to the range [0,1], and the total clamping force weight is... If Wtotal is lower than the minimum contact weight threshold, then the current period is considered to have no effective contact.

[0058] 3. Status Determination

[0059] During the effective contact period, the control unit calculates three core state deviations:

[0060] Clamping deviation Df: Measures the degree of deviation between the actual clamping force and the ideal value.

[0061]

[0062] Where F^ is the estimated clamping force, and Fideal is the preset ideal clamping force;

[0063] Position deviation Dp: Measures the Euclidean distance between the current position and the target position.

[0064]

[0065] Where (x,y,z) are the current position coordinates, and (xtarget,ytarget,ztarget) are the target position coordinates;

[0066] Pressure deviation Da: Used to determine if the gas source is functioning correctly.

[0067]

[0068] Where Pair represents the current air pressure value;

[0069] Subsequently, the comprehensive state coefficient Q is calculated as an overall indicator of whether intervention is needed:

[0070] Q=αDf+βDp+γDa

[0071] Where α, β, and γ are preset weighting coefficients, for example, α=0.5, β=0.3, and γ=0.2.

[0072] 4. Adaptive control decision

[0073] The control unit continuously monitors the Q value and uses a "threshold + dwell" mechanism to resist interference: control commands are only generated when Q continuously exceeds the threshold H and reaches the shortest dwell time Tstay.

[0074] Adjustment direction determination: Compare the contributions of Df, Dp, and Da to Q, and determine the adjustment direction (such as adjusting clamping force, correcting path, or alarm) based on the deviation term with the largest contribution.

[0075] Adjusting the step size Δs quantization: mapping continuous deviations to discrete operation step sizes;

[0076] Calculate the overthreshold amplitude ;

[0077] Calculate the clamping index ;

[0078] Calculate the nominal step size (Where s0 is the minimum step size base, and kq and kt are gain coefficients, for example, s0=1, kq=0.6, kt=0.4).

[0079] The nominal step size is rounded down and saturated to obtain the final adjustment step size. , where Smax is the maximum step size limit, usually set to 2 or 3;

[0080] The control unit provides intuitive prompts to the operator through signal prompting devices (such as tri-color lights) based on the determined adjustment direction and step size.

[0081] 5. Fault diagnosis, reset and recording

[0082] If the control unit detects abnormal sensor data (such as open circuit or saturation), it enters conservative mode: increases the trigger threshold H to limit decision complexity; when the state returns to normal, it executes the reset procedure; at the same time, it records all key data of this event (such as instruction content, deviation value, timestamp) into non-volatile memory to form a traceable data chain.

[0083] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A gantry robot mechanism for practical training and assessment of programmable logic controller (PLC) systems, characterized in that, include: Truss main body (1); A pneumatic slide (4) is installed on the truss body (1) and is used to drive the telescopic cylinder (2) and the pneumatic gripper (3) to move horizontally. Telescopic cylinder (2) is installed on the pneumatic slide (4); The pneumatic gripper (3) is connected to the output end of the telescopic cylinder (2); The control unit is connected to the programmable logic controller (PLC) via signals. Multiple thin-film pressure sensors are uniformly integrated on the clamping surface of the pneumatic gripper (3); A position sensor is used to detect the position of the telescopic cylinder (2) and the pneumatic slide (4); A pneumatic pressure sensor is installed in the pneumatic circuit of the telescopic cylinder (2) and / or the pneumatic gripper (3); A signal prompting device (5) is installed in a conspicuous position on the truss body (1); The control unit is configured to perform the following operations: Establish a unified coordinate reference and calibrate the thin-film pressure sensor, position sensor and air pressure sensor. Preset threshold parameters including minimum effective clamping force threshold Fmin, maximum safe clamping force threshold Fmax, position tolerance Ptol, normal air pressure range [Pmin, Pmax], minimum dwell time Tstay and safe clearing time Tclear. Data from each sensor is collected synchronously during the control cycle Ts, including clamping force estimation F^, current position (x,y,z), and current air pressure value Pair; Based on the collected data, the clamping deviation Df, position deviation Dp, and air pressure deviation Da are calculated, and the weighted sum is used to obtain the comprehensive state coefficient Q=αDf+βDp+γDa, where α, β, and γ are preset weighting coefficients. When the comprehensive state coefficient Q continuously exceeds the preset threshold H and reaches the shortest dwell time Tstay, a control command containing the adjustment direction and adjustment step size Δs is generated, and the signal prompting device (5) is driven to provide a prompt. After the adjustment is completed or the safe clearing conditions are met, the reset procedure is executed, and the relevant data of this event is recorded to non-volatile memory.

2. The gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The gripping surface of the pneumatic gripper (3) is made of flexible material, and the thin-film pressure sensor is evenly distributed along the circumference of the gripping surface and is configured to detect both normal pressure and tangential shear force simultaneously.

3. The gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The control unit includes a non-volatile memory for storing calibration data, threshold parameters, and event logs. The event logs include prompt direction, adjustment step size, and clamping deviation Df and position deviation Dp before and after adjustment.

4. The gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The control unit is configured to calculate the clamping deviation Df using the following formula: Fideal is the preset ideal clamping force.

5. A gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The control unit is configured to calculate the position deviation Dp using the following formula: Where (xtarget, ytarget, ztarget) are the target position coordinates.

6. The gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The control unit is configured to calculate the adjustment step size Δs in the following manner: Calculate the overthreshold amplitude ; Calculate the clamping index ; Calculate the nominal step size Where s0 is the minimum step size base, and kq and kt are gain coefficients; The nominal step size is rounded down and saturated to obtain the final adjustment step size. , where Smax is the maximum step size limit.

7. A gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1 or 7, characterized in that, The control unit is configured such that the adjustment direction is determined based on the deviation term that contributes the most to the overall state coefficient Q among Df, Dp, and Da; if Df contributes the most, the adjustment direction is the clamping force; if Dp contributes the most, the adjustment direction is the transport path; if Da contributes the most, the adjustment direction is the abnormal air pressure alarm.

8. A gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The control unit is configured such that after generating a control command, the system enters a latching state, in which it does not generate new commands repeatedly until a feedback signal indicating successful operation is received or the safe clearing time Tclear is reached.

9. A gantry robot mechanism for practical training and assessment of programmable controller systems according to claim 1, characterized in that, The control unit is configured to: when abnormal sensor channel data or the proportion of failed channels is detected to exceed a set threshold, enter a conservative mode, increase the trigger threshold H, and limit the maximum value of the adjustment step size Δs.

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