System and method for controlling ultra-short cycle reciprocating motion of cutter head of planer

Abstract

The invention provides an ultra-short period reciprocating motion control system and method for a cutter head of a planer. The system comprises a main control module, a driving control module and a signal feedback module which are connected in sequence, the driving control module and the signal feedback module are respectively connected with a motor for controlling the planer tool bit to reciprocate; the signal feedback module is used for acquiring real-time motion information of the motor and feeding back the real-time motion information to the main control module; the main control module is used for calculating the current speed of the motor according to the real-time motion information and determining a driving control strategy based on the current speed and a reciprocating motion instruction from a user; the drive control module is used for executing speed control and forward and reverse reciprocating motion on the motor based on the drive control strategy. When the planer is applied to an orthopaedic arthroscopic surgery, the cutting frequency in unit time can be effectively increased, so that the medical care requirement of efficiently cutting damaged tissues is met, the movement stability and accuracy of the planer tool bit can be ensured, and the surgery efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a control system and method for the ultra-short cycle reciprocating motion of a planer cutter head. Background Technology

[0002] In minimally invasive surgeries such as arthroscopy in orthopedics, powered planers are key devices for cutting and trimming diseased cartilage or bone tissue. Existing planers typically feature a reciprocating motion mode, where the cutter head rotates in both directions within a certain angle range. However, the reciprocating motion cycle of currently available products is relatively long, typically around 500 milliseconds. This results in a limited number of effective cuts per unit time, leading to low surgical efficiency and failing to meet the clinical demand for more efficient and precise manipulation.

[0003] To improve surgical efficiency, the industry has set a goal of shortening the reciprocating motion cycle to the 300-millisecond level. However, achieving such an ultra-short cycle reciprocating motion is not simply a matter of increasing the motor's commutation frequency. While closed-loop control systems capable of precisely controlling motor speed exist in the field of motor control, under ultra-short cycle, high-frequency forward and reverse switching conditions, inherent physical and system factors such as motor inertia, electrical response delay, and control algorithm lag are amplified dramatically. This leads to two serious technical shortcomings that current technologies have not yet addressed: First, the reciprocating motion cycle is difficult to maintain stability, with significant errors and fluctuations between the actual and target cycles; second, during rapid acceleration, deceleration, and commutation, the motor speed is difficult to precisely control within the target range, resulting in unstable cutting forces and affecting surgical outcomes and safety. Therefore, current technologies lack an effective solution that can simultaneously ensure cycle stability and speed accuracy under ultra-short cycle conditions. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a planer cutter head ultra-short cycle reciprocating motion control system and method to solve the problems of long reciprocating motion cycle and low cutting efficiency of the planer in the prior art, and in particular to solve the technical problem of difficulty in simultaneously ensuring cycle stability and motor speed accuracy when achieving ultra-short cycle reciprocating motion at the 300 millisecond level.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: According to a first aspect of the present invention, a planer cutter head ultra-short cycle reciprocating motion control system is provided, the system comprising: a main control module, a drive control module, and a signal feedback module connected in sequence; the drive control module and the signal feedback module are respectively connected to a motor for controlling the planer cutter head to perform reciprocating motion; The signal feedback module is used to acquire the real-time motion information of the motor and feed the real-time motion information back to the main control module; The main control module is used to calculate the current speed of the motor based on the real-time motion information, and determine the drive control strategy based on the current speed and the reciprocating motion command from the user; the reciprocating motion command carries a target speed and a target cycle; the drive control strategy includes at least a PWM signal and motion direction parameters; The drive control module is used to perform speed control on the motor based on the PWM signal, and to perform forward and reverse reciprocating motion on the motor based on the motion direction parameters.

[0006] Furthermore, the drive control module includes an H-bridge drive unit and a controllable phase change unit; the H-bridge drive unit is connected to both the main control module and the controllable phase change unit; the controllable phase change unit is connected to the motor. The H-bridge driving unit includes three parallel H-bridge driving circuits; the H-bridge driving circuit includes an opto-isolation circuit, an anti-dead-zone circuit, and a MOS transistor gate driving circuit connected in sequence. The opto-isolation circuit is used to achieve opto-isolation of the PWM signal; the anti-dead-time circuit is used to prevent dead-time signals from appearing in the PWM signal; the MOS transistor gate drive circuit is used to perform logic processing on the PWM signal to control the motor to rotate according to the target speed. The controllable phase change unit includes a three-phase H-bridge circuit; the three-phase H-bridge circuit is connected to three H-bridge drive circuits respectively, and is used to directly control the motor to perform forward and reverse reciprocating motion according to the target cycle.

[0007] Furthermore, the signal feedback module includes three parallel signal feedback sub-circuits; the motor is respectively connected to the input terminals of the three signal feedback sub-circuits and a Hall encoder installed in the motor, and the output terminals are respectively connected to the main control module; The signal feedback sub-circuit is used to detect the real-time value and pulse jump time interval of the Hall encoder, and output the real-time motion information containing the real-time value and pulse jump time interval to the main control module; The real-time value of the Hall encoder is used to determine the rotor position of the motor; the pulse transition time interval and the rotor position are used to calculate the current speed of the motor.

[0008] Furthermore, the main control module includes a speed calculation unit, a strategy generation unit, and a drive control unit; The speed calculation unit is used to calculate the current speed of the motor based on the real-time value output by the signal feedback sub-circuit and the pulse jump time interval; The strategy generation unit is used to calculate the PWM pulse width value output to the drive control module based on the difference between the current speed and the target speed according to the PID algorithm; and to time the unidirectional motion of the motor according to the target period, and generate motion direction parameters to change the direction of the motor motion when the motor reaches the unidirectional motion duration. The drive control unit is used to input the electrical signals corresponding to the PWM pulse width value and the motion direction parameters to the drive control module, so as to control the motor to perform forward and reverse reciprocating motion according to the target speed and the target period through the drive control module.

[0009] Furthermore, the opto-isolation circuit includes a first optocoupler, a second optocoupler, a first resistor, a second resistor, a third resistor, and a fourth resistor; The first input terminal of the first optocoupler is connected to the second terminal of the first resistor, the second input terminal is connected to the PWM positive output pin of the main control module, the first output terminal is connected to the first output terminal of the second optocoupler and grounded, and the second output terminal is connected to the second terminal of the second resistor and the anti-dead-zone circuit respectively; the first terminal of the first resistor is connected to the first voltage input pin; the first terminal of the second resistor is connected to the first optocoupler and the second voltage pin respectively; The first input terminal of the second optocoupler is connected to the second terminal of the third resistor, the second input terminal is connected to the PWM inverting output pin of the main control module, the first output terminal is connected to the first output terminal of the first optocoupler and grounded, and the second output terminal is connected to the second terminal of the fourth resistor and the anti-dead zone circuit respectively; the first terminal of the third resistor is connected to the first voltage input pin; and the first terminal of the fourth resistor is connected to the second optocoupler and the second voltage pin respectively.

[0010] Furthermore, the anti-dead-zone circuit includes an XOR gate, a first AND gate, a second AND gate, a fifth resistor, and a sixth resistor; The first input pin of the XOR gate is connected to the second terminal of the fifth resistor and the first input pin of the first AND gate, the second input pin is connected to the second terminal of the sixth resistor and the second input pin of the second AND gate, and the output pin is connected to the second input pin of the first AND gate and the first input pin of the second AND gate; the first terminal of the fifth resistor is connected to the second terminal of the second resistor and the second output terminal of the first optocoupler; the first terminal of the sixth resistor is connected to the second terminal of the fourth resistor and the second output terminal of the second optocoupler. The output pins of the first AND gate and the second AND gate are respectively connected to the gate drive circuit of the MOS transistor.

[0011] Furthermore, the MOS transistor gate drive circuit includes an integrated chip, a first capacitor, a second capacitor, a third capacitor, a first diode, a second diode, a third diode, a seventh resistor, and an eighth resistor; The VDD pin of the integrated chip is connected to the first terminal of the first capacitor and the second voltage pin, the HIN pin is connected to the output pin of the first AND gate, the LIN pin is connected to the output pin of the second AND gate, the VSS pin is grounded, the HO pin is connected to the first terminal of the seventh resistor and the cathode of the second diode, the VB pin is connected to the first terminal of the second capacitor and the cathode of the first diode, the VS pin is connected to the second terminal of the second capacitor, the VCC pin is connected to the first terminal of the third capacitor and the anode of the first diode, the COM pin is connected to the second terminal of the third capacitor and grounded, and the LO pin is connected to the cathode of the third diode and the first terminal of the eighth resistor. The second terminal of the first capacitor is grounded; the anode of the first diode is connected to the third voltage pin; the anode of the second diode and the second terminal of the seventh resistor are respectively connected to the driving positive input pin of the controllable phase change unit; the anode of the third diode and the second terminal of the eighth resistor are respectively connected to the driving inverted input pin of the controllable phase change unit.

[0012] Furthermore, the three-phase H-bridge circuit includes a first MOSFET, a second MOSFET, a third MOSFET, a fourth MOSFET, a fifth MOSFET, and a sixth MOSFET; The drains of the first MOSFET, the third MOSFET, and the fifth MOSFET are respectively connected to the power supply voltage input pin; the gates of the first MOSFET, the third MOSFET, and the fifth MOSFET are respectively connected to the drive positive output pins of the three H-bridge drive circuits; the sources of the first MOSFET, the third MOSFET, and the fifth MOSFET are respectively connected to the drains of the second MOSFET, the fourth MOSFET, and the sixth MOSFET, and are connected to the motor. The gates of the second MOS transistor, the fourth MOS transistor, and the sixth MOS transistor are respectively connected to the drive inverted output pins of the three H-bridge drive circuits; the sources of the second MOS transistor, the fourth MOS transistor, and the sixth MOS transistor are respectively grounded.

[0013] Furthermore, the signal feedback sub-circuit includes a ninth resistor, a tenth resistor, a third opto-isolator, and a fourth diode; The first input terminal of the third opto-isolator is connected to the second terminal of the tenth resistor, the second input terminal is connected to the positive terminal of the fourth diode, the first output terminal is grounded, and the second output terminal is connected to the second terminal of the ninth resistor and the signal output pin of the motor, respectively; the first terminal of the ninth resistor is connected to the first voltage input pin and the third opto-isolator, respectively; the first terminal of the tenth resistor is connected to the positive power supply pin of the Hall encoder; and the negative terminal of the fourth diode is connected to the signal input pin of the main control module.

[0014] According to a second aspect of the present invention, a method for controlling the ultra-short cycle reciprocating motion of a planer head is proposed, applied to the ultra-short cycle reciprocating motion control system of a planer head as described in any one of the first aspects of the present invention, the method comprising: The main control module obtains the real-time motion information of the motor and the reciprocating motion command carrying the target speed and target cycle through the signal feedback module; the real-time motion information includes the real-time value of the Hall encoder set in the motor and the pulse transition time interval; The current speed of the motor is calculated based on the real-time motion information, and a PWM pulse width value is generated to control the motor to rotate at the target speed based on the difference between the target speed and the current speed; and motion direction parameters are generated to control the motor to perform forward and reverse reciprocating motion according to the target period. The PWM pulse width value and the motion direction parameter are input to the drive control module. The drive control module performs speed control on the motor based on the PWM pulse width value and performs forward and reverse reciprocating motion on the motor based on the motion direction parameter. The target period is no more than 500 milliseconds.

[0015] The above-described one or more technical solutions provided by this invention can have the following advantages or at least achieve the following technical effects: This invention proposes a control system and method for ultra-short cycle reciprocating motion of a planer cutter head, comprising: a main control module, a drive control module, and a signal feedback module connected in sequence; the drive control module and the signal feedback module are respectively connected to a motor for controlling the reciprocating motion of the planer cutter head; the signal feedback module is used to acquire real-time motion information of the motor and feed the real-time motion information back to the main control module; the main control module is used to calculate the current speed of the motor based on the real-time motion information, and determine a drive control strategy based on the current speed and a reciprocating motion command from the user; the reciprocating motion command carries a target speed and a target cycle; the drive control strategy includes at least a PWM signal and a motion direction parameter; the drive control module is used to perform speed control on the motor based on the PWM signal, and to perform forward and reverse reciprocating motion on the motor based on the motion direction parameter. In orthopedic arthroscopic surgery, this invention can effectively increase the number of cuts per unit time, thereby meeting the medical needs of efficiently cutting damaged tissue, ensuring the motion stability and accuracy of the planer cutter head, and greatly improving surgical efficiency. Attached Figure Description

[0016] 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, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the ultra-short cycle reciprocating motion control system for a planer head according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the ultra-short cycle reciprocating motion control system for the planer head according to another embodiment of the present invention; Figure 3 This is a circuit schematic diagram of an H-bridge driving circuit proposed in an embodiment of the present invention; Figure 4 This is a circuit diagram of a three-phase H-bridge circuit proposed in an embodiment of the present invention; Figure 5 This is a circuit diagram of a signal feedback sub-circuit proposed in an embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the principle of Hall signal output according to an embodiment of the present invention; Figure 7 This is a truth table for clockwise and counterclockwise rotation of a motor, as proposed in an embodiment of the present invention. Figure 8 This is a schematic diagram illustrating the principle of a PID algorithm proposed in an embodiment of the present invention; Figure 9 This is a flowchart illustrating the ultra-short cycle reciprocating motion control method for a planer cutter head according to an embodiment of the present invention.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0020] It should be noted that in this invention, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an apparatus or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an apparatus or system. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the apparatus or system including that element. In this invention, unless otherwise expressly specified and limited, the terms "connected," "fixed," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two elements or an interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0021] like Figure 1 The diagram shown is a structural schematic of a planer cutter head ultra-short cycle reciprocating motion control system proposed in this invention. The system may include: a main control module 10, a drive control module 20, and a signal feedback module 30 connected in sequence; the drive control module 20 and the signal feedback module 30 are respectively connected to a motor (M) for controlling the planer cutter head to perform reciprocating motion.

[0022] Specifically, the signal feedback module 30 can be used to acquire the real-time motion information of the motor and feed the real-time motion information back to the main control module 10; the main control module 10 can be used to calculate the current speed of the motor based on the real-time motion information and determine the drive control strategy based on the current speed and the reciprocating motion command from the user; the drive control module 20 can be used to perform speed control on the motor based on the PWM signal and to perform forward and reverse reciprocating motion on the motor based on the motion direction parameters.

[0023] The reciprocating motion command carries the target speed and target period; the drive control strategy includes at least a PWM signal (i.e., PWM pulse width value) and motion direction parameters. Preferably, the target period can be 300 milliseconds.

[0024] like Figure 2 The figure shows a detailed structural diagram of the ultra-short cycle reciprocating motion control system for the planer head provided in an embodiment of the present invention. As can be seen from the figure, the drive control module 20 may include an H-bridge drive unit 21 and a controllable phase change unit 22; the H-bridge drive unit 21 is connected to both the main control module 20 and the controllable phase change unit 22; the controllable phase change unit 22 is connected to a motor.

[0025] Specifically, the H-bridge drive unit 21 includes three parallel H-bridge drive circuits 210, i.e., it consists of three identical H-bridge drive circuits 210. Each H-bridge drive circuit 210 includes an opto-isolation circuit 2101, an anti-dead-time circuit 2102, and a MOSFET gate drive circuit 2103 connected in sequence. The opto-isolation circuit 2101 is used to implement opto-isolation of the PWM signal. The anti-dead-time circuit 2102 is used to prevent dead-time signals from appearing in the PWM signal. The MOSFET gate drive circuit 2103 is used to perform logic processing on the PWM signal (e.g., converting the PWM signal into a gate drive signal for controlling the MOSFET in the controllable phase-change unit), to control the motor to rotate at the target speed. The controllable phase-change unit 22 includes a three-phase H-bridge circuit 220; the three-phase H-bridge circuit 220 is connected to the three H-bridge drive circuits 210 respectively, and can be used to directly control the motor to perform forward and reverse reciprocating motion according to the target cycle.

[0026] Furthermore, the signal feedback module 30 may include three parallel signal feedback sub-circuits 310; the motor is connected to the input terminals of each of the three signal feedback sub-circuits 310 via Hall encoders installed in the motor, and the output terminals are connected to the main control module 10; the signal feedback sub-circuits 310 are used to detect the real-time value and pulse transition time interval of the Hall encoders, and output the real-time motion information including the real-time value and pulse transition time interval to the main control module 10. The real-time value of the Hall encoder is used to determine the rotor position of the motor; the pulse transition time interval and rotor position are used to calculate the current speed of the motor.

[0027] It can be understood that the main control module 10, drive control module 20, and signal feedback module 30 work together to precisely control the planer motor. Specifically, the signal feedback module 30, connected to the motor, continuously monitors and captures the motor's real-time operating information (such as signals related to current speed and rotor position), and sends this real-time operating information as a feedback signal to the main control module 10. The main control module 10 receives the real-time operating information and compares it with an internally preset target state (such as target speed) to obtain a deviation value. Based on this deviation value, the closed-loop control algorithm running inside the main control module 10 calculates the drive parameters (such as PWM pulse width value) used to correct this deviation. Subsequently, the main control module 10 sends these drive parameters to the drive control module 20. As a function execution part directly connected to the motor, the drive control module 20 outputs corresponding voltage and current to the motor 40 according to the received drive parameters to drive the motor to move in the desired manner. Through such a closed-loop loop of "state monitoring - deviation calculation - parameter adjustment - drive execution," the system can continuously and precisely adjust the motor's motion state. Meanwhile, the main control module 10 also performs a crucial open-loop timing control function, which precisely times each unidirectional movement of the motor. When the timing reaches the preset unidirectional running time (e.g., 150 milliseconds), the main control module 10 generates motion direction parameters to change the motor's motion direction, controlling the drive control module 20 to change the driving mode of the motor, causing its motion direction to reverse. By periodically executing this timing reversal operation, the system can drive the motor to achieve stable periodic reciprocating motion.

[0028] Please refer to the following: Figures 3-5 The circuit structure and connection relationships of each functional module are as follows: like Figure 3As shown, the opto-isolation circuit 2101 may include a first optocoupler (OP1), a second optocoupler (OP2), a first resistor (R3), a second resistor (R1), a third resistor (R8), and a fourth resistor (R6). The first input terminal (1) of the first optocoupler (OP1) is connected to the second terminal of the first resistor (R3), the second input terminal (3) is connected to the PWM positive output pin (PWM-CH1P) of the main control module 10, the first output terminal (4) is connected to the first output terminal (4) of the second optocoupler (OP2) and grounded, and the second output terminal (5) is connected to the second terminal of the second resistor (R1) and the anti-dead zone circuit 2102 respectively; the first terminal of the first resistor (R3) is connected to the first voltage input pin (3V3-IN); the first terminal of the second resistor (R1) is connected to the first optocoupler (OP1) and the second voltage pin (5) respectively. V); the first input terminal (1) of the second optocoupler (OP2) is connected to the second terminal of the third resistor (R8), the second input terminal (3) is connected to the PWM inverting output pin (PWM-CH1N) of the main control module 10, the first output terminal (4) is connected to the first output terminal (4) of the first optocoupler and grounded, the second output terminal (5) is connected to the second terminal of the fourth resistor (R6) and the anti-dead zone circuit 2102 respectively; the first terminal of the third resistor (R8) is connected to the first voltage input pin (3V3-IN); the first terminal of the fourth resistor (R6) is connected to the second optocoupler (OP2) and the second voltage pin (5V).

[0029] The opto-isolation circuit 2101 effectively prevents damage to the main control module 10 caused by motor or external interference signals exceeding the voltage or current capacity of the main control module 10.

[0030] The dead-zone prevention circuit 2102 may include an XOR gate (U3C), a first AND gate (U1C), a second AND gate (U1D), a fifth resistor (R4), and a sixth resistor (R5); the first input pin (9) of the XOR gate (U3C) is connected to the second terminal of the fifth resistor (R4) and the first input pin (9) of the first AND gate (U1C), the second input pin (10) is connected to the second terminal of the sixth resistor (R5) and the second input pin (13) of the second AND gate (U1D), and the output pin (8) is connected to the second terminal of the first AND gate (U1C). The input pin (10) is connected to the first input pin (12) of the second AND gate (U1D); the first end of the fifth resistor (R4) is connected to the second end of the second resistor (R1) and the second output terminal (5) of the first optocoupler (OP1); the first end of the sixth resistor (R5) is connected to the second end of the fourth resistor (R4) and the second output terminal (5) of the second optocoupler (OP2); the output pin (8) of the first AND gate (U1C) and the output pin (11) of the second AND gate (U1D) are connected to the gate drive circuit 2103 of the MOS transistor.

[0031] To prevent the simultaneous conduction of high-side and low-side MOSFETs on the same side in the controllable phase-change unit 22, this embodiment of the invention adds an XOR gate and an AND gate to the H-bridge drive unit 21. This ensures that the PWM signal will never result in the simultaneous conduction of high-side and low-side MOSFETs on the same side, effectively preventing the MOSFETs from burning out due to simultaneous conduction of MOSFETs on the same side of the H-bridge.

[0032] The MOS transistor gate drive circuit 2103 includes an integrated chip (U2), a first capacitor (C1), a second capacitor (C2), a third capacitor (C3), a first diode (D1), a second diode (D2), a third diode (D3), a seventh resistor (R2), and an eighth resistor (R7). The VDD pin of the integrated chip (U2) is connected to the first terminal of the first capacitor (C1) and the second voltage pin (5V). The HIN pin is connected to the output pin (8) of the first AND gate (U1C). The LIN pin is connected to the output pin (11) of the second AND gate (U1D). The VSS pin is grounded. The HO pins are connected to the first terminal of the seventh resistor (R2) and the cathode of the second diode (D2), respectively. The VB pins are connected to the first terminal of the second capacitor (C2) and the first diode (D1). The negative terminal of the first capacitor (C1) is connected to the negative terminal of the first capacitor (C2). The VS pin is connected to the second terminal of the second capacitor (C2). The VCC pin is connected to the first terminal of the third capacitor (C3) and the positive terminal of the first diode (D1). The COM pin is connected to the second terminal of the third capacitor (C3) and grounded. The LO pin is connected to the negative terminal of the third diode (D3) and the first terminal of the eighth resistor (R7). The second terminal of the first capacitor (C1) is grounded. The positive terminal of the first diode (D1) is connected to the third voltage pin (12V). The positive terminal of the second diode (D2) and the second terminal of the seventh resistor (R2) are connected to the positive input pin (drive P) of the controllable phase change unit 22. The positive terminal of the third diode (D3) and the second terminal of the eighth resistor (R7) are connected to the inverted input pin (drive N) of the controllable phase change unit 22.

[0033] Based on the above circuit structure, the main functions of the MOS transistor gate drive circuit 2103 include logic signal input processing, level conversion, and floating bootstrap power supply structure. The logic signal output by the main control module 10 is directly connected to the input channel of the MOS transistor gate drive of the controllable phase change unit 22, so that the main control module 10 can control the motor rotation through the H-bridge.

[0034] like Figure 4The diagram shown is a schematic of a three-phase H-bridge circuit 220. The three-phase H-bridge circuit 220 may include a first MOSFET (Q1), a second MOSFET (Q2), a third MOSFET (Q3), a fourth MOSFET (Q4), a fifth MOSFET (Q5), and a sixth MOSFET (Q6). The drains of the first MOSFET (Q1), the third MOSFET (Q3), and the fifth MOSFET (Q5) are connected to the power supply voltage input pin (VM). The gates of the first MOSFET (Q1), the third MOSFET (Q3), and the fifth MOSFET (Q5) are connected to the positive output pins (drive P) of the three-way H-bridge drive circuit 210. The sources of the first MOSFET (Q1), the third MOSFET (Q3), and the fifth MOSFET (Q5) are connected to the drains of the second MOSFET (Q2), the fourth MOSFET (Q4), and the sixth MOSFET (Q6), respectively, and are connected to the motor. The gates of the second MOSFET (Q2), the fourth MOSFET (Q4), and the sixth MOSFET (Q6) are connected to the inverted output pins (drive N) of the three-way H-bridge drive circuit. The sources of the second MOSFET (Q2), the fourth MOSFET (Q4), and the sixth MOSFET (Q6) are grounded.

[0035] In other words, the circuit consists of six MOSFETs (Q1~6). Q1 and Q2 form the first bridge arm, Q3 and Q4 form the second bridge arm, and Q5 and Q6 form the third bridge arm. The connection points of the upper transistors (Q1, Q3, Q5) and lower transistors (Q2, Q4, Q6) of each bridge arm are connected to the three-phase windings of the motor (e.g., U, V, W phases). The main control module 10, through the H-bridge drive unit 21, controls the conduction and cutoff of these six MOSFETs according to specific timing logic, thereby generating a rotating magnetic field in the motor windings and driving the motor rotor to rotate. For example, by using a six-step commutation method such as "U phase high level, V phase low level, W phase floating" or "U phase high level, W phase low level, V phase floating," the motor can be driven to rotate clockwise or counterclockwise. It can be understood that changing the commutation sequence changes the direction of motor rotation.

[0036] like Figure 5The diagram shows the circuit schematic of the signal feedback sub-circuit 310. The signal feedback sub-circuit 310 may include a ninth resistor (R9), a tenth resistor (R10), a third opto-isolator (OP3), and a fourth diode (D4). The first input terminal (1) of the third opto-isolator (OP3) is connected to the second terminal of the tenth resistor (R10), the second input terminal (3) is connected to the positive terminal of the fourth diode (D4), the first output terminal (4) is grounded, and the second output terminal (5) is connected to the second terminal of the ninth resistor (R9) and the signal output pin (Speed-Back 1) of the motor, respectively. The first terminal of the ninth resistor (R9) is connected to the first voltage input pin (3V3-IN) and the third opto-isolator (OP3), respectively. The first terminal of the tenth resistor (R10) is connected to the positive power supply pin (Hall-VCC) of the Hall encoder. The negative terminal of the fourth diode (D4) is connected to the signal input pin (Hall A) of the main control module 10.

[0037] The signal feedback module 30 determines the position of the motor rotor by detecting the current value of the Hall encoder and calculates the real-time speed of the motor by measuring the pulse transition time interval of the Hall encoder. Typically, three Hall sensors are installed inside the motor at 120-degree electrical angles, forming a Hall encoder. A Hall sensor is a magnetic field sensor based on the Hall effect. The Hall effect refers to the phenomenon where, when a current passes through a semiconductor perpendicular to an external magnetic field, the charge carriers are deflected, generating an additional electric field perpendicular to both the current and the magnetic field, thus creating a potential difference across the semiconductor. This potential difference is also called the Hall potential difference. The combined states of these three Hall signals (Hall A, Hall B, Hall C) (a total of 6 valid states) uniquely correspond to 6 different sectors of the rotor within a 360-degree electrical angle.

[0038] Specifically, in a brushless DC motor, three switching-type Hall effect sensors are typically used to measure the rotor position. Their 3-bit binary output controls the conduction of six MOSFETs in a three-phase, six-arm full-bridge motor to achieve commutation. If a Hall effect sensor is installed close to the rotor, when the N pole gradually approaches the sensor (i.e., the magnetic field reaches a certain value), its output is in a conducting state; as the N pole gradually moves away from the sensor and the magnetic field decreases, its output remains conducting; only when the magnetic field shifts to the S pole and reaches a certain value does the output flip to a cutoff state. With alternating S and N poles, the sensor output waveform occupies 50% high and 50% low levels. If the rotor has one pair of poles, the Hall effect sensor outputs one cycle of voltage waveform per revolution of the motor; if the rotor has two pairs of poles, it outputs two cycles of waveform. In brushless DC motors, three Hall effect sensors are typically installed in a circular pattern with intervals of 120 degrees or 60 degrees. If installed at 120-degree intervals, the output waveforms of the three Hall effect sensors differ by 120 electrical degrees, with the high and low levels each occupying 180 electrical degrees in the output signal. If a high level is represented by "1" and a low level by "0", then the three output signals can be represented using three-bit binary codes, such as... Figure 6 As shown. Figure 6 In the diagram, the black dots at positions a, b, and c represent the positions of the Hall sensors, and the S and N semi-circles represent the rotor of the motor with magnetic poles. Each rotation of the rotor outputs six different signals. Therefore, the three binary codes from the three Hall sensors (a, b, and c) can be used as the rotor's position codes (a complete rotation is 360 degrees; six codes are equivalent to dividing the 360-degree angle into six equal parts, each 60 degrees). Furthermore, the rotor speed can be calculated based on the time intervals between the six signals (since all six signals change once per rotation, the rotor speed is simply the reciprocal of the recorded rotation time; the rotor speed is the motor speed).

[0039] Therefore, by reading these three Hall signals, the main control module 10 can determine the current position and speed of the motor rotor. Correspondingly, these three original Hall signals are also isolated and shaped by optocouplers (OP3, OP4, OP5) to form clean and stable digital signals, which are then input to the main control module 10.

[0040] In this embodiment of the invention, the main control module 10 controls the motor primarily by using the value output by the Hall sensor to activate the MOSFET, thereby enabling the motor to rotate clockwise or counterclockwise. Motor manufacturers typically provide truth tables for clockwise and counterclockwise rotation, such as... Figure 7 As shown. Based on Figure 7As can be seen, when the values ​​of the three Hall sensors are detected, the corresponding MOSFETs are turned on. For example, if Hall a, Hall b, and Hall c are detected as 0, 0, and 1 respectively, then the MOSFETs corresponding to B- and C+ are turned on, while the other MOSFETs remain off. After the corresponding MOSFET is turned on, the motor will rotate by a certain angle. When the next Hall value changes to 101, B- and C+ are turned off, and A+ and B- are turned on. The motor will then rotate by a certain angle until the next Hall value changes. In practical applications, by turning on the corresponding MOSFETs according to the Hall values ​​in the table, the motor can rotate in a certain direction.

[0041] Furthermore, in this embodiment of the invention, the main control module 10 can be implemented by a high-performance microcontroller unit or digital signal processor, etc., which integrates an arithmetic unit, memory, timer / counter, and various communication interfaces. Specifically, the main functions of the main control module 10 can be modularized into a speed calculation unit 110, a strategy generation unit 120, and a drive control unit 130.

[0042] Specifically, the speed calculation unit 110 can be used to calculate the current speed of the motor based on the real-time value output by the signal feedback sub-circuit and the pulse transition time interval. The strategy generation unit 120 can be used to calculate the PWM pulse width value output to the drive control module based on the difference between the current speed and the target speed using a PID algorithm; and to time the unidirectional motion of the motor according to the target period, and generate motion direction parameters to change the direction of motor motion when the motor reaches the unidirectional motion duration. The drive control unit 130 can be used to input the electrical signals corresponding to the PWM pulse width value and the motion direction parameters to the drive control module, so as to control the motor to perform forward and reverse reciprocating motion according to the target speed and the target period through the drive control module.

[0043] The above content has detailed the calculation of the motor's current speed by the speed calculation module 110 and the basic principles of the drive control unit 130 controlling the motor's forward and reverse rotation. It can be understood that to achieve reciprocating motion of the motor at a specific cycle and speed, the main control module 10 only needs to impose time constraints on the motor's forward or reverse motion based on the above principles (controlling the motor to rotate forward for 150ms and then immediately reverse for 150ms, repeating this process, can achieve reciprocating motion of the motor at a specified speed).

[0044] Specifically, the speed calculation unit 110 calculates the current speed information from the pulse signal of the motor's Hall sensor and feeds it back to the strategy generation unit 120. The strategy generation unit 120 calculates the PWM pulse width value based on the current speed information using a PID algorithm and sends it to the drive control unit 130 to achieve speed control. In addition, the strategy generation unit 120 can also implement a periodic timing function, primarily for timing forward and reverse rotation. When its timing reaches 150ms, it sends a parameter signal to control the motor direction and transmits it to the drive control unit 130, thus achieving forward and reverse direction control of the motor. Therefore, it is possible to achieve reciprocating motion control of the motor at a specified speed with an ultra-short cycle of 300ms.

[0045] To enhance the understanding of the present invention by those skilled in the art, the PID algorithm is described in detail below: like Figure 8 The diagram shown illustrates the principle of the PID algorithm. The PID algorithm uses speed feedback from a Hall encoder to sense in real time whether the motor speed has slowed down. Then, by inputting the error between the target speed and the actual speed into the algorithm, the current duty cycle (PWM) can be obtained, achieving speed control. PID is an abbreviation for Proportional, Integral, and Differential; it is a closed-loop control algorithm that combines proportional, integral, and derivative operations. Essentially, PID control uses the result of proportional, integral, and derivative calculations on the error between the target and actual values ​​to affect the output. The ideal PID control law for continuous control can be expressed as:

[0046] Where Kp represents the proportional gain, which is the reciprocal of the proportional gain; Tt represents the integral time constant; TD represents the derivative time constant; u(t) represents the output signal of the PID controller; and e(t) represents the error between the given value r(t) and the measured value.

[0047] Based on this, the strategy generation unit 120 uses the PID algorithm to analyze the current speed and target speed of the motor, obtains the pulse width value of the PWM used to control the motor speed, and controls the direction of the motor by periodic timing, so as to realize the ultra-short cycle reciprocating motion of the motor at a specified speed.

[0048] This invention provides a planer cutter head ultra-short cycle reciprocating motion control system, comprising: a main control module, a drive control module, and a signal feedback module connected in sequence; the drive control module and the signal feedback module are respectively connected to a motor for controlling the planer cutter head to perform reciprocating motion; the signal feedback module is used to acquire real-time motion information of the motor and feed the real-time motion information back to the main control module; the main control module is used to calculate the current speed of the motor based on the real-time motion information, and determine a drive control strategy based on the current speed and the reciprocating motion command from the user; the reciprocating motion command carries a target speed and a target cycle; the drive control strategy includes at least a PWM signal and motion direction parameters; the drive control module is used to perform speed control on the motor based on the PWM signal, and to perform forward and reverse reciprocating motion on the motor based on the motion direction parameters. It has at least the following beneficial effects: 1) This invention achieves ultra-short cycles and improves surgical efficiency. Through precise timing and rapid reversing control of the motor's unidirectional motion, it enables stable reciprocating motion with a cycle time of, for example, 300 milliseconds. Compared to the common 500 millisecond cycle in existing technologies, this invention significantly increases the effective number of ablation operations per unit time, thereby greatly improving surgical efficiency.

[0049] 2) It ensures precise and stable motion. By introducing a closed-loop control algorithm based on real-time motor operating status feedback, this invention can compensate for speed fluctuations of the motor during high-speed commutation, ensuring that the rotational speed of the cutter head is precisely controllable throughout the entire motion process, thereby guaranteeing the stability of the cutting force and the quality and safety of the surgery.

[0050] 3) Improved system reliability. In some preferred embodiments, by setting up opto-isolation circuits, the core controller can be effectively protected from electrical interference and shocks on the power side; by setting up dead-zone protection circuits, the risk of short-circuit burnout caused by simultaneous conduction of the upper and lower transistors of the bridge arm can be effectively prevented, significantly improving the stability and reliability of the entire control system.

[0051] Furthermore, such as Figure 9 As shown, embodiments of the present invention also provide an application for, for example Figure 1 The method for controlling the ultra-short cycle reciprocating motion of the planer head in the ultra-short cycle reciprocating motion control system shown includes steps S901~S903: In step S901, the main control module obtains the real-time motion information of the motor and the reciprocating motion command carrying the target speed and target cycle through the signal feedback module; the real-time motion information includes the real-time value of the Hall encoder set in the motor and the pulse transition time interval. Step S902: Calculate the current speed of the motor based on the real-time motion information, and generate a PWM pulse width value to control the motor to rotate at the target speed based on the difference between the target speed and the current speed; and generate motion direction parameters to control the motor to perform forward and reverse reciprocating motion according to the target cycle. In step S903, the PWM pulse width value and motion direction parameters are input to the drive control module. The drive control module performs speed control on the motor based on the PWM pulse width value and performs forward and reverse reciprocating motion on the motor based on the motion direction parameters.

[0052] It should be noted that the specific implementation methods of each step in the ultra-short cycle reciprocating motion control method for the planer head provided in this embodiment of the invention can be found in the following references. Figure 1 The corresponding descriptions of the functional modules in the system shown are not repeated here.

[0053] It should be noted that the sequence numbers of the above embodiments of the present invention are merely for descriptive purposes and do not represent the superiority or inferiority of the embodiments. The above descriptions are only optional embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made under the concept of the present invention using the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

[0054] The foregoing description of the specifications and embodiments is intended to explain the scope of protection of this invention, but does not constitute a limitation on the scope of protection of this invention. Modifications, equivalent substitutions, or other improvements to the embodiments of this invention or a portion thereof that can be obtained by those skilled in the art through logical analysis, reasoning, or limited experimentation, based on the teachings of this invention or the foregoing embodiments, in conjunction with common knowledge, general technical knowledge, and / or existing technology, should all be included within the scope of protection of this invention.

Claims

1. A shaver head ultra-short cycle reciprocating motion control system, characterized in that, The system comprises a main control module, a drive control module and a signal feedback module connected in sequence; the drive control module and the signal feedback module are connected to a motor for controlling the reciprocating motion of the planer cutter head; The signal feedback module is configured to acquire real-time motion information of the motor and feed the real-time motion information back to the main control module; The main control module is configured to calculate a current speed of the motor according to the real-time motion information and determine a drive control strategy based on the current speed and a reciprocating motion instruction from a user; the reciprocating motion instruction carries a target speed and a target period; the drive control strategy comprises at least a PWM signal and a motion direction parameter; The drive control module is configured to perform speed control on the motor based on the PWM signal and perform forward and reverse reciprocating motion on the motor based on the motion direction parameter.

2. The system of claim 1, wherein, The drive control module comprises an H-bridge drive unit and a controllable phase change unit; the H-bridge drive unit is connected to the main control module and the controllable phase change unit; the controllable phase change unit is connected to the motor; The H-bridge drive unit comprises three H-bridge drive circuits connected in parallel; the H-bridge drive circuit comprises an opto-isolator circuit, a dead zone prevention circuit and a MOS gate drive circuit connected in sequence; The opto-isolator circuit is configured to realize photoelectric isolation of the PWM signal; the dead zone prevention circuit is configured to prevent dead zone signals from appearing in the PWM signal; The MOS gate drive circuit is configured to perform logic processing on the PWM signal to control the motor to rotate at the target speed; The controllable phase change unit comprises a three-phase H-bridge circuit; the three-phase H-bridge circuit is connected to three H-bridge drive circuits respectively, and is configured to directly control the motor to perform forward and reverse reciprocating motion at the target period.

3. The system of claim 1, wherein, The signal feedback module comprises three signal feedback sub-circuits connected in parallel; the motor is connected to a Hall encoder arranged in the motor at the input end of the three signal feedback sub-circuits respectively, and is connected to the main control module at the output end; The signal feedback sub-circuit is configured to detect a real-time value and a pulse jump time interval of the Hall encoder, and output real-time motion information comprising the real-time value and the pulse jump time interval to the main control module; The real-time value of the Hall encoder is used to determine a rotor position of the motor; the pulse jump time interval and the rotor position are used to calculate a current speed of the motor.

4. The system of claim 3, wherein, The main control module comprises a speed calculation unit, a strategy generation unit and a drive control unit; The speed calculation unit is configured to calculate the current speed of the motor according to the real-time value and the pulse jump time interval output by the signal feedback sub-circuit; The strategy generation unit is configured to calculate a PWM pulse width value output to the drive control module according to a PID algorithm based on a difference between the current speed and the target speed; and time the unidirectional motion of the motor according to the target period, and generate a motion direction parameter for changing the motion direction of the motor when the motor reaches the unidirectional motion duration. The drive control unit is configured to input an electrical signal corresponding to the PWM pulse width value and the motion direction parameter to the drive control module, so as to control the motor to perform forward and reverse reciprocating motion at the target speed and the target period through the drive control module.

5. The system of claim 2, wherein, The optoelectronic isolation circuit comprises a first optoelectronic coupler, a second optoelectronic coupler, a first resistor, a second resistor, a third resistor and a fourth resistor; The first input end of the first optoelectronic coupler is connected to the second end of the first resistor, the second input end is connected to the PWM positive output pin of the main control module, the first output end is connected to the first output end of the second optoelectronic coupler and grounded, and the second output end is connected to the second end of the second resistor and the dead zone prevention circuit respectively; the first end of the first resistor is connected to the first voltage input pin; and the first end of the second resistor is connected to the first optoelectronic coupler and the second voltage pin respectively. The first input end of the second optoelectronic coupler is connected to the second end of the third resistor, the second input end is connected to the PWM negative output pin of the main control module, the first output end is connected to the first output end of the first optoelectronic coupler and grounded, and the second output end is connected to the second end of the fourth resistor and the dead zone prevention circuit respectively; the first end of the third resistor is connected to the first voltage input pin; and the first end of the fourth resistor is connected to the second optoelectronic coupler and the second voltage pin respectively.

6. The system of claim 5, wherein, The dead zone prevention circuit comprises an XOR gate, a first AND gate, a second AND gate, a fifth resistor and a sixth resistor; The first input pin of the XOR gate is connected to the second end of the fifth resistor and the first input pin of the first AND gate respectively, the second input pin is connected to the second end of the sixth resistor and the second input pin of the second AND gate respectively, the output pin is connected to the second input pin of the first AND gate and the first input pin of the second AND gate respectively; the first end of the fifth resistor is connected to the second end of the second resistor and the second output end of the first optoelectronic coupler respectively; and the first end of the sixth resistor is connected to the second end of the fourth resistor and the second output end of the second optoelectronic coupler respectively. The output pin of the first AND gate and the output pin of the second AND gate are connected to the MOS gate drive circuit.

7. The system of claim 6, wherein, The MOS gate drive circuit comprises an integrated chip, a first capacitor, a second capacitor, a third capacitor, a first diode, a second diode, a third diode, a seventh resistor and an eighth resistor; The VDD pin of the integrated chip is connected with the first end of the first capacitor and the second voltage pin, the HIN pin is connected with the output pin of the first AND gate, the LIN pin is connected with the output pin of the second AND gate, the VSS pin is grounded, the HO pin is connected with the first end of the seventh resistor and the negative electrode of the second diode, respectively, the VB pin is connected with the first end of the second capacitor and the negative electrode of the first diode, respectively, the VS pin is connected with the second end of the second capacitor, the VCC pin is connected with the first end of the third capacitor and the positive electrode of the first diode, respectively, the COM pin is connected with the second end of the third capacitor and grounded, and the LO pin is connected with the negative electrode of the third diode and the first end of the eighth resistor, respectively. The second end of the first capacitor is grounded, the positive electrode of the first diode is connected with the third voltage pin, the positive electrode of the second diode and the second end of the seventh resistor are connected with the driving positive phase input pin of the controllable phase change unit, respectively, and the positive electrode of the third diode and the second end of the eighth resistor are connected with the driving negative phase input pin of the controllable phase change unit, respectively.

8. The system of claim 2, wherein, The three-phase H-bridge circuit comprises a first MOS transistor, a second MOS transistor, a third MOS transistor, a fourth MOS transistor, a fifth MOS transistor and a sixth MOS transistor. The drain of the first MOS transistor, the drain of the third MOS transistor and the drain of the fifth MOS transistor are connected with a power voltage input pin, respectively; the gate of the first MOS transistor, the gate of the third MOS transistor and the gate of the fifth MOS transistor are connected with a driving positive phase output pin of the H-bridge driving circuit, respectively; the source of the first MOS transistor, the source of the third MOS transistor and the source of the fifth MOS transistor are connected with the drain of the second MOS transistor, the drain of the fourth MOS transistor and the drain of the sixth MOS transistor, respectively, and are connected with the motor. The gate of the second MOS transistor, the gate of the fourth MOS transistor and the gate of the sixth MOS transistor are connected with a driving negative phase output pin of the H-bridge driving circuit, respectively; the source of the second MOS transistor, the source of the fourth MOS transistor and the source of the sixth MOS transistor are grounded, respectively.

9. The system of claim 3, wherein, The signal feedback sub-circuit comprises a ninth resistor, a tenth resistor, a third opto-isolator and a fourth diode. The first input end of the third opto-isolator is connected with the second end of the tenth resistor, the second input end is connected with the positive electrode of the fourth diode, the first output end is grounded, and the second output end is connected with the second end of the ninth resistor and the signal output pin of the motor, respectively; the first end of the ninth resistor is connected with a first voltage input pin and the third opto-isolator, respectively; the first end of the tenth resistor is connected with the positive electrode power supply pin of the Hall encoder; and the negative electrode of the fourth diode is connected with the signal input pin of the master control module.

10. A method of ultra-short cycle reciprocating motion control of a shaver head, characterized in that, The method is applied to the super-short-period reciprocating motion control system of the shaver head, and the method comprises: The main control module acquires real-time motion information of the motor and reciprocating motion instructions carrying a target speed and a target period through a signal feedback module; the real-time motion information includes real-time values of a Hall encoder arranged in the motor and pulse jump time intervals; A current speed of the motor is calculated according to the real-time motion information, and a PWM pulse width value for controlling the motor to rotate at the target speed is generated according to a difference between the target speed and the current speed; and a motion direction parameter for controlling the motor to perform forward and reverse reciprocating motion at the target period is generated; The PWM pulse width value and the motion direction parameter are input to a drive control module, the drive control module performs speed control on the motor based on the PWM pulse width value, and performs forward and reverse reciprocating motion on the motor based on the motion direction parameter; The target period is not more than 500 milliseconds.

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