A calibration method and driving method for a tension hook module

Abstract

This application discloses a calibration and driving method for a tension hook module, belonging to the field of semiconductor device bonding technology. The method includes driving the tension hook sequentially through N position points to obtain N optimal first current values; installing a gauge block on the tension hook and driving it through N more position points to obtain N optimal second current values; calculating the mechanical resistance and torque coefficient corresponding to each position point based on the optimal first and second current values, thereby constructing an equation relating the mechanical resistance, torque coefficient, and the position of the tension hook. This application obtains the current values ​​at the same position points by sequentially moving the tension hook under no-load and load conditions, constructing an equation relating the mechanical resistance, torque coefficient, and the position of the tension hook, obtaining the magnitude of the mechanical resistance and torque coefficient at relative positions, thereby calculating the input current of the voice coil motor and controlling the tension of the tension hook to be the same at each position.

Description

Technical Field

[0001] This application belongs to the field of semiconductor device bonding technology, and relates to a calibration method and driving method for a tension hook module. Background Technology

[0002] In the semiconductor industry, signal communication between chips and electrical interconnection between chips and substrates are achieved through wire bonding. Bonding machines use ultrasonic bonding to weld wires to chips and substrates. After bonding, a tension hook module is usually used to apply a fixed force to the wires to perform a tension test and detect unqualified wires.

[0003] Due to the mechanical structure design, the resistance of the tension hook module varies at different positions in the height direction. The magnetic field experienced by the motor's mover also changes accordingly during the movement. Reasonable and effective calibration of the tension hook module directly affects the accuracy of the voice coil motor's output. Therefore, the tension hook module needs to be calibrated before conducting a tension test on the lead wire. Existing calibration methods have low accuracy and are complicated to operate. Summary of the Invention

[0004] To address the problems in related technologies, this application provides a calibration method and a driving method for a tension hook module, the specific technical solution of which is as follows:

[0005] In a first aspect, this application provides a calibration method for a tension hook module. The calibration method employs a tension hook testing device, which includes a controller and a tension hook module. The tension hook module includes a tension hook, an elastic element, and a voice coil motor. The voice coil motor outputs a driving force to drive the tension hook to hook the thread. The elastic element is disposed at the output driving end of the voice coil motor to balance the driving force. The controller collects the current of the voice coil motor. The calibration method for the tension hook module includes:

[0006] Based on the stroke range of the tension hook, determine N position points located within the stroke range, where N≥2;

[0007] The voice coil motor is controlled to drive the tension hook to pass through the N position points in sequence. The current of the voice coil motor is sampled to obtain N optimal first current values ​​corresponding to the N position points.

[0008] A gauge block of weight m is installed on the tension hook. The voice coil motor is controlled to drive the tension hook with the gauge block installed to pass through the N position points in sequence. The current of the voice coil motor is sampled to obtain N optimal second current values ​​corresponding to the N position points.

[0009] Based on the optimal first current value and optimal second current value corresponding to the N position points, the mechanical resistance and torque coefficient corresponding to each position point are calculated respectively. The mechanical resistance is the resistance generated by the elastic element, and the torque coefficient is the torque coefficient of the voice coil motor.

[0010] Based on the mechanical resistance and torque coefficient corresponding to the N position points, an equation is constructed relating the mechanical resistance, torque coefficient, and the position of the tension hook. In the equation, the position of the tension hook is the dependent variable, and the mechanical resistance and torque coefficient are the independent variables.

[0011] Optionally, determining N position points within the stroke range of the tension hook includes:

[0012] The travel range is divided into N-1 segments, and the starting position of the travel range and the position of the endpoint of each segment away from the starting position are taken as the N position points.

[0013] Optionally, controlling the voice coil motor to drive the tension hook to sequentially pass through the N position points, sampling the current of the voice coil motor, and obtaining N optimal first current values ​​corresponding one-to-one with the N position points includes:

[0014] The voice coil motor is controlled to drive the tension hook to pass through the N position points in sequence, and the current of the voice coil motor is sampled to obtain N first current values;

[0015] Perform Kalman filtering on each of the first current values ​​to obtain N optimal first current values.

[0016] Optionally, sampling the current of the voice coil motor to obtain N first current values ​​includes:

[0017] At each position point, the current of the voice coil motor is sampled M times to obtain M first initial current values ​​corresponding to each position point;

[0018] For each location point, the M initial current values ​​of the location point are calculated to obtain the first current value of the location point.

[0019] Optionally, the step of calculating the M initial current values ​​at the location point to obtain the first current value at the location point includes:

[0020] From the M initial current values ​​at the given location point, select M-2 initial current values ​​other than the maximum and minimum values;

[0021] Calculate the average of the M-2 initial current values, and use the average value as the first current value at the location point.

[0022] Optionally, the voice coil motor is controlled to drive the tension hook with the gauge block mounted thereon to pass through the N position points in sequence, and the current of the voice coil motor is sampled to obtain N optimal second current values ​​corresponding one-to-one with the N position points, including:

[0023] The voice coil motor is controlled to drive the tension hook to pass through the N position points in sequence, and the current of the voice coil motor is sampled to obtain N second current values;

[0024] Perform Kalman filtering on each of the second current values ​​to obtain N optimal second current values.

[0025] Optionally, sampling the current of the voice coil motor to obtain N second current values ​​includes:

[0026] At each position point, the current of the voice coil motor is sampled M times to obtain M second initial current values ​​corresponding to each position point;

[0027] For each location point, the M second initial current values ​​of the location point are calculated to obtain the second current value of the location point.

[0028] Optionally, the step of calculating the M second initial current values ​​at the location point to obtain the second current value at the location point includes:

[0029] From the M second initial current values ​​at the given location point, select M-2 second initial current values ​​other than the maximum and minimum values;

[0030] Calculate the average value of the M-2 second initial current values, and use the average value as the second current value at the location point.

[0031] Optionally, the step of performing Kalman filtering on each of the first current values ​​to obtain N optimal first current values ​​includes:

[0032] Each of the first current values ​​is subjected to Kalman filtering. The N first current values ​​after Kalman filtering are then subjected to error screening. The correct first current values ​​are calculated and saved to obtain the N optimal first current values.

[0033] Optionally, the step of performing error screening on the N first current values ​​after Kalman filtering, calculating and saving the correct first current values, and obtaining the N optimal first current values ​​includes:

[0034] For the i-th first current value after Kalman filtering, determine whether the i-th first current value is greater than the (i-1)-th first current value and less than the (i+1)-th first current value, where i ≥ 2;

[0035] If the i-th first current value is greater than the (i-1)-th first current value and less than the (i+1)-th first current value, then the i-th first current value is taken as the i-th optimal first current value.

[0036] If the i-th first current value is not greater than the (i-1)-th first current value or not less than the (i+1)-th first current value, then calculate the average value of the (i-1)-th first current value and the (i+1)-th first current value, and take the average value as the i-th optimal first current value.

[0037] Optionally, Kalman filtering is performed on each of the second current values ​​to obtain N optimal second current values, including:

[0038] Each second current value is subjected to Kalman filtering. Error screening is performed on the N second current values ​​after Kalman filtering. The correct second current values ​​are calculated and saved to obtain the N optimal second current values.

[0039] Optionally, the step of performing error screening on the N second current values ​​after Kalman filtering, calculating and saving the correct second current values, and obtaining the N optimal second current values ​​includes:

[0040] For the i-th second current value after Kalman filtering, determine whether the i-th second current value is greater than the (i-1)-th second current value and less than the (i+1)-th second current value, where i ≥ 2;

[0041] If the i-th second current value is greater than the (i-1)-th second current value and less than the (i+1)-th second current value, then the i-th second current value is taken as the i-th optimal second current value.

[0042] If the i-th second current value is not greater than the (i-1)-th second current value or not less than the (i+1)-th second current value, then calculate the average value of the (i-1)-th second current value and the (i+1)-th second current value, and take the average value as the i-th optimal second current value.

[0043] Secondly, this application also provides a driving method for a tension hook module, the driving method for the tension hook module comprising:

[0044] The current position of the tension hook is detected by a position sensor;

[0045] Using the calibration method of the tension hook module provided in the first aspect, the equations relating mechanical resistance, torque coefficient, and the position of the tension hook are constructed to calculate the mechanical resistance and torque coefficient at the current position:

[0046] Based on the mechanical resistance and torque coefficient at the current position, and the predetermined applied tension, the input current for controlling the voice coil motor is calculated, and the voice coil motor drives the tension hook according to the input current.

[0047] Based on the above technical solution, this application can achieve at least the following beneficial effects:

[0048] By controlling the tension hook to perform unloaded movement and loaded movement after installing gauge blocks, and detecting the current value at the same position, an equation can be constructed for the mechanical resistance, torque coefficient, and position of the tension hook. The mechanical resistance and torque coefficient at any position can be calculated, which facilitates the calculation of the input current of the voice coil motor, thereby achieving the effect of controlling the tension hook to have the same tension at any position.

[0049] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit the invention. Attached Figure Description

[0050] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0051] Figure 1 This is a schematic diagram of the tension hook module used in one embodiment of this application;

[0052] Figure 2 This is a flowchart of a calibration method for a tension hook module provided in one embodiment of this application;

[0053] Figure 3 This is a schematic diagram of a tension hook module with gauge blocks installed in one embodiment of this application;

[0054] Figure 4 This is a flowchart of a driving method for a tension hook module provided in one embodiment of this application. Detailed Implementation

[0055] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0056] Figure 1This is a schematic diagram of the tension hook module used in one embodiment of this application. The calibration method for the tension hook module provided in this application employs a tension hook testing device, which includes a controller and a tension hook module. The tension hook module includes a tension hook 4, an elastic element 3, and a voice coil motor 2. The voice coil motor 2 outputs driving force to drive the tension hook 4 to hook the thread. The elastic element 3 is disposed at the output driving end of the voice coil motor 2 to balance the driving force. The controller is used to collect the current of the voice coil motor 2. In a possible real-time implementation, the elastic element 3 may include a tension spring and a spring sheet, which together act on the tension hook 4 to provide mechanical resistance to the tension hook 4.

[0057] Figure 2 This is a flowchart of a calibration method for a tension hook module provided in one embodiment of this application. The calibration method for this tension hook module is applied to... Figure 1 The tension hook module shown is calibrated. The calibration of this tension hook module can be achieved through software, hardware, or a combination of both. The following section will discuss this in conjunction with... Figure 1 The calibration method for the tension hook module provided in this application is described, and the calibration method may include the following steps:

[0058] Step 101: Control the tension hook to pass through N position points in sequence;

[0059] In practical applications, N position points (N≥2) within the stroke range of the tension hook are first determined. Then, the voice coil motor drives the tension hook to sequentially pass through these N position points. In one feasible implementation, the stroke range of the tension hook is divided into N-1 equal segments, and the starting position of the stroke range and the position of the endpoint of each segment furthest from the starting position are designated as the N position points. Optionally, the initial position of the tension hook can be recorded as the first position point, and the extreme position of the tension hook from the initial position can be recorded as the Nth position point. The position of the tension hook can be detected and monitored in real time using a PSD position sensor.

[0060] See also Figure 1 The initial position of the tension hook is the upper limit. Under the action of the elastic element, as the position moves to the lower limit, the mechanical resistance gradually increases. The direction of the mechanical resistance is upward. At the same time, as the mover of the voice coil motor moves downward, the influence of the stator magnetic field on the mover will also change nonlinearly.

[0061] When the voice coil motor is given a positive current, it outputs a downward force; conversely, it outputs an upward force. Therefore, when the tension hook is positioned at a certain location under the drive of the voice coil motor, it must satisfy the following mechanical equation:

[0062] F f -K e *I A=0 (1)

[0063] Among them, I A When installing gauge blocks, the controller collects the second current value of the motor at each predetermined position;

[0064] In one possible implementation, the entire stroke range of the tension hook module is defined as 0 to S_Max (mm). The entire stroke is divided into N-1 segments. The more segments the stroke is divided into, the higher the accuracy of piecewise linear interpolation. The stroke interval of each segment is:

[0065] S_Step=S_Max / (N-1) (2)

[0066] The initial position of the tension hook is the upper limit position. The upper limit position is used as the reference point, i.e., 0mm. The tension hook is positioned at intervals of S_Step, with the upper limit position as the initial value.

[0067] Step 102: Sample and obtain N optimal first current values;

[0068] In one possible implementation, a voice coil motor is controlled to drive a tension hook through N position points sequentially. At each position point, the controller samples the current of the voice coil motor M times to obtain M initial current values ​​corresponding to each position point. For each position point, the average of the M initial current values ​​collected at that position point is calculated to obtain the corresponding initial current value.

[0069] Optionally, when calculating the average value of the first initial current value, first select M-2 first initial current values ​​from the M first initial current values, excluding the maximum and minimum values ​​(i.e., remove one maximum value and one minimum value), then calculate the average value of the remaining M-2 first initial current values, and use the calculated average value as the first current value at that location point. The average value is calculated for each location point using the above method, ultimately yielding N first current values ​​corresponding to the N location points.

[0070] In one possible implementation, after each pull hook moves to a designated position, the controller continuously samples the voice coil motor current at that moment and stores it in the controller buffer. The size of the buffer, Buff_A, is equal to 10 (i.e., 10 initial current values ​​are sampled continuously at each position), and the sampled initial current value is denoted as I. Buff_1 I Buff_2 I Buff_3 I Buff4 I Buff5 I Buff6 I Buff7 I Buff8 I Buff9I Buff10 The 10 initial current values ​​collected from the buffer are evaluated. After removing the maximum and minimum values, the average value is calculated to obtain I. A1 I A1 Using the first current value at the current position as an example, we can obtain the first current value at all positioning positions, denoted as I. A1 I A2 ... I AN After the tension hook obtains the first current value at all positions, it returns to the upper limit position.

[0071] Optionally, after calculating N first current values, Kalman filtering is performed on each first current value to obtain N optimal first current values ​​corresponding to the N location points. In one possible implementation, to remove noise and ensure that the acquired current values ​​truly reflect the actual current values, Kalman filtering is performed on all first current values, i.e., for I... A1 I A2 ... I AN After performing Kalman filtering, I is obtained A_Filter1 I A_Filter2 ... I A_FilterN The filtered data is stored in the controller's buffer Buff_A_Filter to obtain the final N first current values.

[0072] Under the action of the elastic element, the resistance of the tension hook gradually increases from the upper limit to the lower limit. The current collected by the controller should also show a gradual increasing trend. Therefore, error screening can be performed on the N first current values ​​after Kalman filtering, and the correct first current values ​​can be calculated and saved to obtain the N optimal first current values. The specific error screening method is as follows:

[0073] For the i-th first current value after Kalman filtering, determine whether the i-th first current value is greater than the (i-1)-th first current value and less than the (i+1)-th first current value, where i ≥ 2. If the i-th first current value is greater than the (i-1)-th first current value and less than the (i+1)-th first current value, then the i-th first current value is taken as the i-th optimal first current value. If the i-th first current value is not greater than the (i-1)-th first current value or not less than the (i+1)-th first current value, then calculate the average of the (i-1)-th and (i+1)-th first current values ​​and take this average as the i-th optimal first current value.

[0074] Taking the fifth first current value after Kalman filtering as an example, if the fifth first current value satisfies the condition that it is greater than the fourth first current value and less than the sixth first current value, then the fifth first current value at this time is taken as the fifth optimal first current value; otherwise, the average value of the fourth and sixth first current values ​​is recorded as the fifth optimal first current value.

[0075] In one possible implementation, the buffer Buff_A_Filter uses the second data as the starting point for screening, and determines whether the current data to be screened, denoted as Ii, is greater than Ii-1 and less than Ii+1. If the condition is met, the next data to be screened is then judged. If the condition is not met, the current data to be screened is changed to the average of Ii-1 and Ii+1, as shown in Equation 3 below. This process continues until the last data IN is screened.

[0076] I i =(I i-1 +I i+1 ) / twenty three)

[0077] Step 103: Install gauge blocks on the tension hook;

[0078] Figure 3 This is a schematic diagram of a tension hook module with gauge blocks installed in one embodiment of this application, as shown below. Figure 3 As shown, gauge block 5 is detachably mounted on the drive end of tension hook 4, providing downward resistance to tension hook 4.

[0079] Step 104: Control the tension hook with gauge blocks installed to pass through N position points in sequence;

[0080] Optionally, the weight of the gauge block can be selected as 100g. The above extreme position is used as the reference point. The tension hook is also positioned at intervals of S_Step, and the above extreme position is used as the initial positioning point.

[0081] When the hook moves to the same position, due to the pulling force, a weight M is placed on the hook to exert a certain weight. g Then the following mechanical equations must be satisfied:

[0082] F f -M g -K e *I B =0 (4)

[0083] Among them, M g It is known that I B When installing gauge blocks, the controller collects the second current value of the motor at each predetermined position; it should be noted that the controller collects I... A and I BAt the same time, the positions of the motors are the same, ultimately resulting in a one-to-one correspondence of I. A and I B value.

[0084] Step 105: Sample and obtain N optimal second current values;

[0085] In one possible implementation, a voice coil motor is controlled to drive a tension hook with a gauge block mounted on it through N position points in sequence. At each position point, the controller samples the current of the voice coil motor M times to obtain M second initial current values ​​corresponding to each position point. For each position point, the average of the M second initial current values ​​collected at that position point is calculated to obtain the second current value corresponding to that position point.

[0086] Optionally, when calculating the average value of the second initial current value, first select M-2 second initial current values ​​from the M second initial current values, excluding the maximum and minimum values ​​(i.e., remove one maximum and one minimum value), then calculate the average value of the remaining M-2 second initial current values, and use the calculated average value as the second current value at that location point. The average value is calculated for each location point using the above method, ultimately yielding N second current values ​​corresponding to the N location points.

[0087] In one possible implementation, after each pull hook moves to a designated position, the controller continuously samples the voice coil motor current at that moment and stores it in the controller buffer. The size of the buffer, Buff_B, is equal to 10 (i.e., 10 second initial current values ​​are sampled continuously at each position). The sampled current is denoted as I. Buff_1 I Buff_2 I Buff_3 I Buff4 I Buff5 I Buff6 I Buff7 I Buff8 I Buff9 I Buff10 The ten second initial current values ​​collected from the buffer are evaluated. After removing the maximum and minimum values, the average value is calculated to obtain I. B1 I B1 As the second current value at the current position, and so on, the second current value at all positioning positions can be obtained, denoted as I. B1 I B2 ... I BN After obtaining the second current value at all positions, the tension hook returns to the upper limit position.

[0088] Under the action of the elastic element, the resistance of the tension hook gradually increases from the upper limit to the lower limit. The current collected by the controller should also show a gradual increasing trend. Therefore, after calculating N second current values, Kalman filtering can be applied to each second current value to obtain N optimal second current values ​​corresponding to the N position points. In one possible implementation, similar to the first current value, to reduce noise, I... B1 I B2 ... I BN Perform Kalman filtering to obtain I B_Filter1 I B_Filter2 ... I B_FilterN+1 The filtered data is stored in the buffer Buff_B_Filter to obtain the final N second current values.

[0089] In one possible implementation, error screening is performed on the N second current values ​​after Kalman filtering, and the correct second current values ​​are calculated and saved to obtain the N optimal second current values. The specific error screening method is as follows:

[0090] For the i-th second current value after Kalman filtering, determine whether the i-th second current value is greater than the (i-1)-th second current value and less than the (i+1)-th second current value, where i ≥ 2. If the i-th second current value is greater than the (i-1)-th second current value and less than the (i+1)-th second current value, then the i-th first current value is taken as the i-th optimal second current value. If the i-th second current value is not greater than the (i-1)-th second current value or not less than the (i+1)-th second current value, then calculate the average of the (i-1)-th and (i+1)-th second current values ​​and take this average as the i-th optimal second current value.

[0091] Taking the fifth second current value after Kalman filtering as an example, if the fifth second current value satisfies the condition that it is greater than the fourth second current value and less than the sixth second current value, then the fifth second current value at this time is taken as the fifth optimal second current value; otherwise, the average value of the fourth and sixth second current values ​​is recorded as the fifth optimal second current value.

[0092] In one possible implementation, the buffer Buff_B_Filter uses the second data point as the starting point for screening. It checks whether the current data to be screened, denoted as Ii, is greater than Ii-1 and less than Ii+1. If the condition is met, the next data to be screened is then evaluated. If the condition is not met, the current data to be screened is changed to the average of Ii-1 and Ii+1, following the calculation method shown in Equation 3, until the last data Ii. N The screening is complete.

[0093] Step 106: Construct the relationship equation between mechanical resistance, torque coefficient and the position of the tension hook.

[0094] In one possible implementation, by combining the equations related to the optimal first current and the optimal second current in steps 102 and 105, equations 1 and 4 above can be used to construct the relationship equation between mechanical resistance, torque coefficient and the position of the tension hook, thereby determining the magnitude of the mechanical resistance and torque coefficient at each position point.

[0095] Specifically, based on the optimal first current value and optimal second current value obtained by collecting and calculating the current at the same location using the tension hook, N F values ​​can be obtained by combining equations 1 and 4. f Value and K e The values ​​are denoted as F. f1 F f2 ... F fN and K e1 K e2 ... K eN According to Formula 5 for piecewise linear difference, the relationship equations between mechanical resistance and torque coefficient and the position of the tension hook can be obtained respectively.

[0096]

[0097] In Equation 5, (x1, y1) and (x2, y2) are two known points.

[0098] Therefore, the equations relating the mechanical resistance and torque coefficient of the tension hook to the position are shown in Equation 6 below.

[0099]

[0100] In Equation 6, i = 0, 1, 2...N-1, j = 1, 2...N, and x represents the position information of the tension hook.

[0101] In summary, the calibration method for the tension hook module provided in this application controls the tension hook to perform no-load movement and load movement after installing gauge blocks, and detects the current value at the same position point respectively, thereby constructing an equation for mechanical resistance, torque coefficient and the position of the tension hook. The mechanical resistance and torque coefficient at any position can be calculated, which is convenient for calculating the input current of the voice coil motor.

[0102] Figure 4 This is a flowchart of a driving method for a tension hook module provided in one embodiment of this application. The driving method for the tension hook module provided in this application is to drive the tension hook module after calibrating it using the calibration method provided in this application. The driving method for the tension hook module includes the following steps:

[0103] Step 401: Detect the current position of the tension hook using a position sensor;

[0104] Step 402: Using the equations for mechanical resistance, torque coefficient and position of the tension hook constructed by the calibration method of the tension hook module described above, calculate the mechanical resistance and torque coefficient at the current position;

[0105] Step 403: Determine the tension of the tension hook according to the process requirements;

[0106] Step 404: Calculate the input current used to control the voice coil motor based on the determined pulling force and the calculated mechanical resistance and torque coefficient at the current position;

[0107] Step 405: The voice coil motor drives the tension hook to move according to the calculated input current.

[0108] The position information of the tension hook is detected in real time by the PSD position sensor and fed back to the microcontroller. Based on the position information of the tension hook, the Ff value and Ke value of the current position are calculated by Equation 6. After obtaining the Ff value and Ke value of the current position, the voice coil motor calculates the expected current value required by the voice coil motor according to the output force requirement by Equation 7. The expected current value is sent to the current loop closed-loop control, which drives the tension hook to hook the wire with the set force to achieve the purpose of detecting the wire welding status.

[0109]

[0110] In Equation 7, F req To set the output power, F f F represents the magnitude of the resistance at the current position. req F f The unit is gram (g), I set The unit is ampere (A) and kJ. e The unit is grams per ampere (g / A).

[0111] In summary, the driving method of the tension hook module provided in this application detects the current position of the tension hook by a position sensor, calculates the mechanical resistance and torque coefficient at the current position by combining a predetermined equation of mechanical resistance, torque coefficient and position of the tension hook, and then calculates the input current of the voice coil motor according to the preset tension value of the tension hook, thereby controlling the movement of the tension hook to provide a corresponding tension.

[0112] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the application filed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not claimed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the appended claims.

[0113] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A calibration method for a tension hook module, characterized in that, The calibration method for the tension hook module employs a tension hook testing device. This device includes a controller and a tension hook module. The tension hook module comprises a tension hook, an elastic element, and a voice coil motor. The voice coil motor outputs a driving force to drive the tension hook to hook the soldered thread. The elastic element is positioned at the output drive end of the voice coil motor to balance the driving force. The controller collects the current from the voice coil motor. The calibration method for the tension hook module includes: Based on the stroke range of the tension hook, determine N position points located within the stroke range, where N≥2; The voice coil motor is controlled to drive the tension hook to pass through the N position points in sequence. The current of the voice coil motor is sampled to obtain N optimal first current values ​​corresponding to the N position points. A gauge block of weight m is installed on the tension hook. The voice coil motor is controlled to drive the tension hook with the gauge block installed to pass through the N position points in sequence. The current of the voice coil motor is sampled to obtain N optimal second current values ​​corresponding to the N position points. Based on the optimal first current value and optimal second current value corresponding to the N position points, the mechanical resistance and torque coefficient corresponding to each position point are calculated respectively. The mechanical resistance is the resistance generated by the elastic element, and the torque coefficient is the torque coefficient of the voice coil motor. Based on the mechanical resistance and torque coefficient corresponding to the N position points, an equation is constructed relating the mechanical resistance, torque coefficient, and the position of the tension hook. In the equation, the position of the tension hook is the dependent variable, and the mechanical resistance and torque coefficient are the independent variables.

2. The calibration method for the tension hook module according to claim 1, characterized in that, The step of determining N position points within the stroke range of the tension hook includes: The travel range is divided into N-1 segments, and the starting position of the travel range and the position of the endpoint of each segment away from the starting position are taken as the N position points.

3. The calibration method for the tension hook module according to claim 1, characterized in that, The process involves controlling the voice coil motor to drive the tension hook through the N position points sequentially, sampling the current of the voice coil motor, and obtaining N optimal first current values ​​corresponding to the N position points, including: The voice coil motor is controlled to drive the tension hook to pass through the N position points in sequence, and the current of the voice coil motor is sampled to obtain N first current values; Perform Kalman filtering on each of the first current values ​​to obtain N optimal first current values.

4. The calibration method for the tension hook module according to claim 3, characterized in that, The sampling of the current of the voice coil motor yields N first current values, including: At each position point, the current of the voice coil motor is sampled M times to obtain M first initial current values ​​corresponding to each position point; For each location point, the M initial current values ​​of the location point are calculated to obtain the first current value of the location point.

5. The calibration method for the tension hook module according to claim 4, characterized in that, The calculation of the M initial current values ​​at the location point to obtain the first current value at the location point includes: From the M initial current values ​​at the given location point, select M-2 initial current values ​​other than the maximum and minimum values; Calculate the average value of the M-2 initial current values, and use the average value as the first current value at the location point.

6. The calibration method for the tension hook module according to claim 1, characterized in that, The voice coil motor is controlled to drive the tension hook with the gauge block mounted thereon to pass through the N position points in sequence. The current of the voice coil motor is sampled to obtain N optimal second current values ​​corresponding one-to-one with the N position points, including: The voice coil motor is controlled to drive the tension hook to pass through the N position points in sequence, and the current of the voice coil motor is sampled to obtain N second current values; Perform Kalman filtering on each of the second current values ​​to obtain N optimal second current values.

7. The calibration method for the tension hook module according to claim 6, characterized in that, The sampling of the current of the voice coil motor yields N second current values, including: At each position point, the current of the voice coil motor is sampled M times to obtain M second initial current values ​​corresponding to each position point; For each location point, the M second initial current values ​​of the location point are calculated to obtain the second current value of the location point.

8. The calibration method for the tension hook module according to claim 7, characterized in that, The calculation of the M second initial current values ​​at the location point to obtain the second current value at the location point includes: From the M second initial current values ​​at the given location point, select M-2 second initial current values ​​other than the maximum and minimum values; Calculate the average value of the M-2 second initial current values, and use the average value as the second current value at the location point.

9. The calibration method for the tension hook module according to claim 3, characterized in that, The process of performing Kalman filtering on each of the first current values ​​to obtain N optimal first current values ​​includes: Each of the first current values ​​is subjected to Kalman filtering. The N first current values ​​after Kalman filtering are then subjected to error screening. The correct first current values ​​are calculated and saved to obtain the N optimal first current values.

10. The calibration method for the tension hook module according to claim 9, characterized in that, The step of performing error screening on the N first current values ​​after Kalman filtering, calculating and saving the correct first current values, and obtaining the N optimal first current values ​​includes: For the i-th first current value after Kalman filtering, determine whether the i-th first current value is greater than the (i-1)-th first current value and less than the (i+1)-th first current value, where i ≥ 2; If the i-th first current value is greater than the (i-1)-th first current value and less than the (i+1)-th first current value, then the i-th first current value is taken as the i-th optimal first current value. If the i-th first current value is not greater than the (i-1)-th first current value or not less than the (i+1)-th first current value, then calculate the average value of the (i-1)-th first current value and the (i+1)-th first current value, and take the average value as the i-th optimal first current value.

11. The calibration method for the tension hook module according to claim 6, characterized in that, Kalman filtering is performed on each of the second current values ​​to obtain N optimal second current values, including: Each second current value is subjected to Kalman filtering. Error screening is performed on the N second current values ​​after Kalman filtering. The correct second current values ​​are calculated and saved to obtain the N optimal second current values.

12. The calibration method for the tension hook module according to claim 11, characterized in that, The step of performing error screening on the N second current values ​​after Kalman filtering, calculating and saving the correct second current values, and obtaining the N optimal second current values ​​includes: For the i-th second current value after Kalman filtering, determine whether the i-th second current value is greater than the (i-1)-th second current value and less than the (i+1)-th second current value, where i ≥ 2; If the i-th second current value is greater than the (i-1)-th second current value and less than the (i+1)-th second current value, then the i-th second current value is taken as the i-th optimal second current value. If the i-th second current value is not greater than the (i-1)-th second current value or not less than the (i+1)-th second current value, then calculate the average value of the (i-1)-th second current value and the (i+1)-th second current value, and take the average value as the i-th optimal second current value.

13. A driving method for a tension hook module, characterized in that, The driving method of the tension hook module includes: The current position of the tension hook is detected by a position sensor; Using the calibration method of the tension hook module as described in claim 1, the equations relating mechanical resistance, torque coefficient, and the position of the tension hook are constructed to calculate the mechanical resistance and torque coefficient at the current position. Based on the mechanical resistance and torque coefficient at the current position, and the predetermined applied tension, the input current for controlling the voice coil motor is calculated, and the voice coil motor drives the tension hook according to the input current.

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