Milling drill equipment, control method and robot

Abstract

The embodiment of the invention discloses milling and drilling equipment, a control method and a robot, the milling and drilling equipment comprises a cutter main shaft, a wave spring, a brushless motor and a driving unit which are arranged in a sealed shell, and further comprises the brushless motor and the driving unit provided with three layers of circuit boards; the driving unit is used for acquiring a rotation parameter of the brushless motor and a stretching parameter of the wave spring; and the control current of the brushless motor is determined on the basis of the relation between the axial pressure of the tool spindle and the cutting force of the milling drill bit through the rotation parameters and the telescopic parameters, and the brushless motor is controlled through the control current to drive the milling drill bit to act through the tool spindle. The technical problems that in the prior art, milling and drilling equipment is low in control precision and cannot dynamically adapt to different operation requirements are solved, and the technical effects that the motor can be dynamically regulated and controlled, and the control precision of the motor is improved are achieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of medical devices, and in particular to a milling drill device, a control method and a robot. Background Art

[0002] Precise drilling and milling operations are crucial in brain surgery. However, existing surgical instruments often have problems such as insufficient precision and inability to dynamically adapt to different surgical needs during use, which makes traditional surgical instruments limited in achieving precise control and operational flexibility, and cannot meet the requirements of complex brain surgery. Summary of the invention

[0003] The embodiments of the present invention provide a milling drill device, a control method and a robot, which solve the technical problems in the prior art that the milling drill device has low control accuracy and cannot dynamically adapt to different surgical requirements.

[0004] An embodiment of the present invention provides a milling drill device, the milling drill device comprising a sealed housing, a tool spindle, a wave spring, a brushless motor, and a drive unit provided with a three-layer circuit board;

[0005] The tool spindle, the wave spring, the brushless motor and the drive unit are all arranged in the sealed housing;

[0006] The tail of the tool spindle is fixedly connected to the rotor of the brushless motor, the head of the tool spindle is provided with a milling drill bit, and the tail of the rotor of the brushless motor is provided with a radial magnet;

[0007] The wave spring is fixed between the tail of the tool spindle and the brushless motor;

[0008] The driving unit is arranged at an end of the radial magnet away from the tail of the rotor, and a gap of a preset distance is arranged between the driving unit and the radial magnet;

[0009] The first layer of the circuit board of the driving unit is used to obtain the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring; the second layer of the circuit board of the driving unit is used to use the rotation parameters and the expansion and contraction parameters to determine the control current of the brushless motor based on the relationship between the axial pressure of the tool spindle and the cutting force of the milling drill bit, and use the control current to control the brushless motor to drive the milling drill bit to move through the tool spindle; the third layer of the circuit board of the driving unit is used to provide a stabilized power supply for the driving unit.

[0010] Furthermore, a rotary Hall sensor and a linear Hall sensor are integrated on the first layer circuit board of the driving unit; three half H-bridge chips, a main control chip and a sampling module are integrated on the second layer circuit board of the driving unit; a power management chip, a voltage regulator chip and a filtering module are integrated on the third layer circuit board of the driving unit.

[0011] Furthermore, the sampling module includes at least two current sampling resistors; and the filtering module includes at least two filtering capacitors.

[0012] Furthermore, the three layers of circuit boards of the driving unit are connected to each other in communication via pin headers.

[0013] Furthermore, it also includes a power supply unit;

[0014] The power supply unit is fixed to an end of the driving unit away from the brushless motor; the power supply unit is arranged in the sealed housing.

[0015] Further, it also includes a saline tube;

[0016] The physiological saline tube is fixed to the outside of the sealing shell along the direction of the tool spindle, and the tube mouth of the physiological saline tube is arranged at the milling drill bit;

[0017] The saline tube is used to cool and clean the milling drill bit using saline.

[0018] Furthermore, the power supply unit includes a battery.

[0019] An embodiment of the present invention further provides a control method for a milling drill device. The milling drill device described in any of the above embodiments executes the control method, and the control method includes:

[0020] The first layer circuit board of the driving unit obtains the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring;

[0021] The second circuit board of the driving unit determines the axial pressure of the tool spindle based on the telescopic parameter;

[0022] The second circuit board determines the control current of the brushless motor using the rotation parameter based on the relationship between the axial pressure and the cutting force of the milling drill bit;

[0023] The second layer circuit board uses the control current to control the brushless motor to drive the milling drill to move through the tool spindle based on a magnetic field oriented control algorithm.

[0024] Furthermore, the second layer circuit board uses the control current to control the brushless motor to drive the milling drill through the tool spindle based on the magnetic field oriented control algorithm, and the action includes:

[0025] The second layer circuit board collects the current three-phase current of the brushless motor through a sampling module;

[0026] The main control chip of the second layer circuit board performs Clarke transformation using the current three-phase current to obtain a two-phase static reference system current;

[0027] The main control chip performs Park transformation using the two-phase stationary reference frame current to obtain a two-phase rotating reference frame current;

[0028] The main control chip determines the two-phase rotating reference system voltage based on PI control using the two-phase rotating reference system current and the target current, wherein the target current is the control current;

[0029] The main control chip uses the two-phase rotating reference frame voltage to perform an inverse Park transformation to obtain a two-phase stationary reference frame voltage;

[0030] The main control chip uses the two-phase stationary reference frame voltage to perform Clarke inverse transformation to obtain a target three-phase voltage, and uses the target three-phase voltage to control the brushless motor to drive the milling drill to move through the tool spindle.

[0031] An embodiment of the present invention further provides a robot, which includes a mechanical arm and the milling drill device described in any of the above embodiments; the milling drill device is arranged on the mechanical arm, and the mechanical arm drives the milling drill device to perform corresponding actions.

[0032] The embodiment of the present invention discloses a milling drill device, a control method and a robot. The milling drill device includes a tool spindle, a wave spring, a brushless motor and a drive unit arranged in a sealed housing, and also includes a brushless motor and a drive unit provided with a three-layer circuit board; the tail of the tool spindle is fixedly connected to the rotor of the brushless motor, the head of the tool spindle is provided with a milling drill bit, and the tail of the rotor of the brushless motor is provided with a radial magnet; the first layer of the circuit board of the drive unit is used to obtain the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring; the second layer of the circuit board of the drive unit is used to use the rotation parameters and the expansion and contraction parameters to determine the control current of the brushless motor based on the relationship between the axial pressure of the tool spindle and the cutting force of the milling drill bit, and use the control current to control the brushless motor to drive the milling drill bit to move through the tool spindle; the third layer of the circuit board of the drive unit is used to provide a stabilized power supply for the drive unit. The present invention determines the control current of the brushless motor by using the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring through a drive unit provided with a three-layer circuit board, so that the brushless motor can dynamically adjust the motor power, speed and torque, thereby solving the technical problems in the prior art that the control accuracy of the milling drill equipment is low and cannot dynamically adapt to different surgical requirements, and achieves the technical effect of being able to dynamically regulate the motor and improving the control accuracy of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is an appearance diagram of a milling drilling device provided by an embodiment of the present invention;

[0034] Figure 2 is a structural diagram of a milling drilling device provided by an embodiment of the present invention;

[0035] Figure 3 is a detailed view of a radial magnet of a milling drill device provided by an embodiment of the present invention;

[0036] Figure 4 is a structural diagram of a driving unit provided by an embodiment of the present invention;

[0037] Figure 5 is a detailed diagram of a driving unit under a viewing angle provided by an embodiment of the present invention;

[0038] Figure 6 is a detailed view of a driving unit at another viewing angle provided by an embodiment of the present invention;

[0039] Figure 7 is a flow chart of a control method of a milling drilling device provided by an embodiment of the present invention;

[0040] Figure 8 It is a schematic diagram of a surgical robot provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0042] It should be noted that the terms "first", "second", etc. in the specification, claims and drawings of the present invention are used to distinguish different objects, rather than to limit a specific order. The following embodiments of the present invention can be implemented separately, or in combination with each other, and the embodiments of the present invention do not impose specific limitations on this.

[0043] Figure 1 The figure is an appearance diagram of a milling drilling device provided by an embodiment of the present invention. Figure 2 It is a structural diagram of a milling drilling device provided by an embodiment of the present invention. Figure 3 It is a detailed view of a radial magnet of a milling drill device provided by an embodiment of the present invention.

[0044] like Figure 1-3 As shown, the milling drill equipment includes a sealed housing 10, a tool spindle 20, a wave spring 30, a brushless motor 40 and a drive unit 50 provided with a three-layer circuit board; the tool spindle 20, the wave spring 30, the brushless motor 40 and the drive unit 50 are all arranged in the sealed housing 10; the tail of the tool spindle 20 is fixedly connected to the rotor of the brushless motor 40, the head of the tool spindle 20 is provided with a milling drill bit 21, and the tail of the rotor of the brushless motor 40 is provided with a radial magnet 60; the wave spring 30 is fixed between the tail of the tool spindle 20 and the brushless motor 40; the drive unit 50 is arranged at one end of the radial magnet 60 away from the tail of the rotor, and a gap of a preset distance is provided between the drive unit 50 and the radial magnet 60.

[0045] The first layer circuit board 51 of the driving unit 50 is used to obtain the rotation parameters of the brushless motor 40 and the expansion and contraction parameters of the wave spring 30; the second layer circuit board 52 of the driving unit 50 is used to use the rotation parameters and the expansion and contraction parameters to determine the control current of the brushless motor 40 based on the relationship between the axial pressure of the tool spindle 20 and the cutting force of the milling drill bit 21, and use the control current to control the brushless motor 40 to drive the milling drill bit 21 through the tool spindle 20; the third layer circuit board 53 of the driving unit 50 is used to provide a regulated power supply for the driving unit 50.

[0046] Specifically, see Figure 1-Figure 3The sealed housing 10 can ensure that a sterile environment is maintained inside the milling drill equipment through its sealing design process, and can ensure the cleanliness and working safety of the inside of the equipment. The tool spindle 20 is fixed to the inside of the sealed housing 10 through bearings 22 on both sides. The tail of the tool spindle 20 is fixed to the rotor of the brushless motor 40, and the milling drill bit 21 for the milling drill is fixed to the head of the tool spindle 20. The wave spring 30 is installed between the bearing for fixing the tail of the tool spindle 20 and the end face of the sealed housing 10. The wave spring 30 has a pre-pressure and can produce axial displacement when the tool spindle 20 is compressed in the axial direction. A radial magnet 60 is provided at the tail of the rotor of the brushless motor 40, and the brushless motor 40 can provide efficient and stable power output. The drive unit 50 includes a three-layer circuit board, which is responsible for the overall control and power management of the milling drill equipment.

[0047] The milling drill equipment can be used by hand or can be set on a robotic arm and controlled by a robot. When the milling drill equipment is started for use, the brushless motor 40 starts to drive the milling drill bit 21 to work through the tool spindle 20. When the milling drill bit 21 cuts the target, it applies a pressure to the wave spring 30 through the tool spindle 20, causing the wave spring 30 to expand and contract. When the wave spring 30 is compressed, the first layer circuit board 51 of the drive unit 50 detects the rotation parameters of the brushless motor 40 and the expansion and contraction parameters of the wave spring 30, wherein the rotation parameters at least include the current speed and current torque of the brushless motor 40, and the expansion and contraction parameters at least include the expansion and contraction amount of the wave spring 30; the second layer circuit board 52 of the drive unit 50 can use the rotation parameters and expansion and contraction parameters acquired in real time based on the axial pressure F of the tool spindle 20 axial The cutting force F of the milling drill 21 cut The control current I of the brushless motor 40 is determined by the relationship between them, and finally the brushless motor 40 is controlled according to the determined control current I, so that the position, speed and torque of the brushless motor 40 can be accurately and dynamically regulated in real time.

[0048] Among them, the axial pressure F axial With cutting force F cut The relationship between cut =f(F axial ) can be obtained through experiments. Specifically, experiments can be conducted based on similar materials to the target to be cut. For example, when a milling drill is needed to cut human bones during surgery, a material similar to human bone tissue can be used in advance and placed on a six-dimensional force sensor. The six-dimensional force sensor can be used to determine the axial pressure F when cutting human bone tissue through experiments. axial With cutting force F cut and establish the functional relationship F cut =f(Faxial ) to guide torque application in subsequent surgery.

[0049] The present invention determines the control current of the brushless motor by using the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring through a drive unit provided with a three-layer circuit board, so that the brushless motor can dynamically adjust the motor power, speed and torque, thereby solving the technical problems in the prior art that the control accuracy of the milling drill equipment is low and cannot dynamically adapt to different surgical requirements, and achieves the technical effect of being able to dynamically regulate the motor and improving the control accuracy of the motor.

[0050] Figure 4 It is a structural diagram of a driving unit provided by an embodiment of the present invention. Figure 5 This is a detailed diagram of a driving unit under a viewing angle provided by an embodiment of the present invention. Figure 6 It is a detailed view of a driving unit from another viewing angle provided by an embodiment of the present invention.

[0051] Alternatively, if Figure 4-6 As shown, a rotary Hall sensor 511 and a linear Hall sensor 512 are integrated on the first-layer circuit board 51 of the driving unit 50; three half-H-bridge chips 521, a main control chip 522 and a sampling module 523 are integrated on the second-layer circuit board 52 of the driving unit 50; a power management chip 531, a voltage regulator chip 532 and a filtering module 533 are integrated on the third-layer circuit board 53 of the driving unit 50.

[0052] In an alternative embodiment, Figure 5-6 As shown, the sampling module 523 includes at least two current sampling resistors; and the filtering module 533 includes at least two filtering capacitors.

[0053] Alternatively, if Figure 4-6 As shown, the three layers of the circuit board of the driving unit 50 are connected to each other in communication via pin headers 54 .

[0054] Specifically, participate in Figure 4-6, the first layer of circuit board 51 is provided with a rotary Hall sensor 511, a linear Hall sensor 512 and other electrical components; the second layer of circuit board 52 is provided with a main control chip 522, three half-H bridge chips 521, two current sampling resistors (i.e. the sampling module 523 mentioned above) and other electrical components; the three half-H bridge chips 521 each have two MOS tubes, forming a three-phase inverter circuit of 6 MOS tubes. The third layer of circuit board 53 is provided with a power management chip 531, a voltage stabilizing chip 532, two filter capacitors (i.e. the filter module 533 mentioned above) and other electrical components. Among them, the second layer of circuit board 52 realizes efficient control of the brushless motor 40 through the FOC (Field Oriented Control) algorithm. The FOC algorithm specifically includes Clarke transformation and its inverse transformation, Park transformation and its inverse transformation, etc., to ensure that the brushless motor 40 can run accurately and adapt to different surgical requirements. The third layer of circuit board 53 can also provide a regulated power supply for the drive unit 50, and the filter module 533 arranged thereon can process the control signal to make the signal more stable.

[0055] Alternatively, if Figure 3 As shown, the milling drill device further includes a power supply unit 70; the power supply unit 70 is fixed to one end of the driving unit 50 away from the brushless motor 40; the power supply unit 70 is disposed in the sealed housing 10. Optionally, the power supply unit 70 includes a battery.

[0056] Specifically, the power supply unit 70 is used to provide electric power. A battery is arranged in the power supply unit 70 so that the milling drill device can continue to work without an external power supply.

[0057] Alternatively, if Figure 1 As shown, it also includes a saline tube 80; the saline tube 80 is fixed to the outside of the sealed housing 10 along the direction of the tool spindle 20, and the tube mouth of the saline tube 80 is set at the milling drill bit 21; the saline tube 80 is used to use saline to cool and clean the milling drill bit 21.

[0058] The milling drilling equipment provided by the embodiment of the present invention has the following advantages:

[0059] (1) High-precision control. By acquiring the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring in real time, the FOC algorithm is used to determine the precise control current, thereby achieving real-time and precise control of the brushless motor and ensuring the stability and accuracy of the tool spindle during surgery.

[0060] (2) Highly integrated design. The design of the integrated drive unit includes three layers of circuit boards, each of which is responsible for parameter detection, logic control, power management, and signal processing, making the milling drilling equipment more compact and highly integrated.

[0061] (3) Sterile environment. The design of the sealed shell ensures that the surgical instruments work in a sterile environment, ensuring the safety of the operation and the cleanliness of the instruments.

[0062] (4) Dynamic adaptability. By acquiring the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring in real time, and using the relationship between the axial pressure of the tool spindle and the cutting force of the milling drill bit to determine the control current of the brushless motor, the torque output of the brushless motor can be adjusted in real time by controlling the current. This can dynamically adapt to different surgical needs, improve surgical flexibility, and meet the needs of complex brain surgery.

[0063] Figure 7 It is a flow chart of a control method of a milling drilling device provided by an embodiment of the present invention.

[0064] The milling drilling device in any of the above embodiments executes the control method, such as Figure 7 As shown, the control method of the milling drilling equipment specifically includes the following steps:

[0065] S701 , the first layer circuit board 51 of the driving unit 50 obtains the rotation parameters of the brushless motor 40 and the expansion and contraction parameters of the wave spring 30 .

[0066] Specifically, the rotation parameters include at least the current rotation speed v and current torque T of the brushless motor 40, and the expansion and contraction parameters include at least the expansion and contraction amount x of the wave spring 30. The rotation Hall sensor 511 and the linear Hall sensor 512 provided on the first layer circuit board 51 are used to obtain the rotation parameters of the brushless motor 40 and the expansion and contraction parameters of the wave spring 30, respectively.

[0067] S702 , the second circuit board 52 of the driving unit 50 determines the axial pressure of the tool spindle 20 based on the telescopic parameter.

[0068] Specifically, the main control chip 522 of the second layer circuit board 52 of the driving unit 50 can determine the axial pressure F of the tool spindle 20 based on the expansion and contraction amount x in the expansion and contraction parameter and Hooke's law F=k*x. axial , then the axial pressure F axial =k*x, where k is the stiffness coefficient of the wave spring 30.

[0069] S703 , the second circuit board 52 determines the control current of the brushless motor using the rotation parameter based on the relationship between the axial pressure and the cutting force of the milling drill bit 21 .

[0070] Specifically, the output torque of the brushless motor 40 is related to its current. According to the characteristics of the motor, the motor torque can be calculated by the following formula: T=K t *I, where T is the output torque of the brushless motor, in N·m (Newton·meter); K tis the torque constant of the brushless motor, in Newton-meter / ampere; I is the current of the brushless motor, in A (ampere).

[0071] In order to keep the brushless motor 40 at a certain speed, the axial pressure F axial The change of the control current I of the brushless motor 40 is dynamically adjusted to control the output motor torque T. The motor torque T is used as the cutting torque T of the milling drill bit. cut , which can be achieved by the cutting force F of the milling drill 21 cut And the cutting point radius r is calculated to get: T cut =F cut *r, and the axial pressure F axial With cutting force F cut The relationship between can be obtained through experiments. Specifically, experiments can be conducted based on similar materials of the target to be cut. Similar materials can be placed on a six-dimensional force sensor, and the axial pressure F when cutting the material can be determined through experiments using the six-dimensional force sensor. axial With cutting force F cut and establish the functional relationship F cut =f(F axial ). Then according to the calculation formula of motor torque: , thus obtaining the control current I0 of the brushless motor.

[0072] S704 , the second layer circuit board 52 controls the brushless motor 40 to drive the milling drill 21 to move through the tool spindle 20 using the control current based on the field oriented control algorithm (FOC algorithm).

[0073] Optionally, in S704, the second layer circuit board 52 controls the brushless motor 40 to drive the milling drill 21 through the tool spindle 20 by controlling the current based on the magnetic field oriented control algorithm, including:

[0074] The second circuit board 52 collects the current three-phase current i of the brushless motor 40 through the sampling module 523 a 、i b 、i c The main control chip 522 of the second circuit board 52 uses the current three-phase current i a 、i b 、i c Perform Clarke transformation to obtain the two-phase stationary reference system current i α 、i β ; The main control chip 522 uses the two-phase static reference system current i α 、i β Perform Park transformation to obtain the two-phase rotating reference frame current i d 、i qThe main control chip 522 uses the two-phase rotating reference system current i based on PI control (Proportional Integral Control, proportional-integral control) d 、i q And the target current determines the two-phase rotating reference voltage V d 、V q , where the target current is the control current I0; the main control chip 522 uses the two-phase rotating reference system voltage V d 、V q Perform inverse Park transform to obtain the two-phase stationary reference voltage V α 、V β The main control chip 522 uses the two-phase static reference voltage V α 、V β Perform Clarke inverse transformation to obtain the target three-phase voltage V a 、V b 、V c , and use the target three-phase voltage V a 、V b 、V c Control the brushless motor to drive the milling drill through the tool spindle.

[0075] Specifically, the Clarke transform is: , where i a 、i b 、i c are the three-phase currents of the brushless motor, i α 、i β They are the two-phase static reference system currents. After Clarke transformation, the current component i α 、i β It is equivalent to converting the three-phase current i a 、i b 、i c Projection in an orthogonal coordinate system can simplify the calculation. Similarly, the inverse Clarke transform is used to convert the two-phase stationary reference system voltage V α 、V β Convert back to the target three-phase voltage V a 、V b 、V c , the formula is: .

[0076] Park transformation is to transform the two-phase stationary reference frame current i α 、i β Converted into two-phase rotating reference frame current i d 、i q A mathematical transformation of , whose formula is: , where θ is the rotor angle of the brushless motor, i.e. the above-mentioned rotation parameter, which is acquired by the rotating Hall sensor. The Park transform converts the current in the stationary reference frame to the reference frame that rotates synchronously with the rotor to perform vector control of the motor. Similarly, the inverse Park transform can convert the rotating reference frame voltage back to the stationary reference frame voltage, and its formula is: .

[0077] Based on PI control, the two-phase rotating reference system current i d 、i q And the target current I0 determines the two-phase rotating reference voltage V d 、V q The calculation formulas are: , , where i d0 and i q0 is the two-phase rotating reference frame current converted from the target current I0, Kp and Ki are the proportional gain and integral gain of the PI controller respectively.

[0078] After obtaining the target three-phase voltage V a 、V b 、V c Afterwards, the MOS tube is switched on and off by a PWM (Pulse Width Modulation) signal to adjust the voltage of the brushless motor 40. The MOS tube is a component of three half H-bridge chips 521 integrated on the second layer circuit board 52.

[0079] An embodiment of the present invention further provides a robot, which includes a mechanical arm and the milling drill device in any of the above embodiments; the milling drill device is arranged on the mechanical arm, and the mechanical arm drives the milling drill device to perform corresponding actions.

[0080] For example, Figure 8 is a schematic diagram of a surgical robot provided by an embodiment of the present invention, such as Figure 8 As shown, the milling drill device 81 is arranged on the mechanical arm 82, and the mechanical arm 82 drives the milling drill device 81 to perform corresponding actions. The mechanical arm 82 monitors and compensates the position error of the end effector of the mechanical arm 82 (i.e., the milling drill device 81) in real time through the forward kinematics and inverse kinematics algorithms, as well as the application of the force Jacobian matrix, to ensure that the tool spindle of the milling drill device 81 maintains a stable position during the cutting process.

[0081] Specifically, the position compensation algorithm principle of the robot arm 82 holding the milling drill device 81 is:

[0082] First, the actual position of the end effector of the robot arm 82 (i.e., the milling drill device 81) is calculated based on the displacement of the tool spindle 20 through the forward kinematics algorithm; the actual position and posture of the end effector can be calculated based on the joint angles and structural parameters of the robot arm 82 using the forward kinematics algorithm.

[0083] Second, the calculated actual position is compared with the target position to obtain the position error; the position error includes translation error (x, y, z direction) and rotation error (rotation angle around the x, y, z axis).

[0084] Third, position compensation calculation is performed based on the position error. Based on the position error, the compensation amount of each joint of the robot arm 82 is calculated through the inverse kinematics algorithm. The inverse kinematics algorithm converts the position error into angle compensation of each joint to ensure that the end effector of the robot arm 82 returns to the target position.

[0085] Fourth, the application of the force Jacobian matrix. The force Jacobian matrix is ​​used to convert external forces (such as the force on the tool spindle) into forces and torques on the joints. The force Jacobian matrix defines the relationship between the position change of the end effector and the torque change of each joint. The joint torque calculated by the force Jacobian matrix is ​​used to dynamically adjust the motor torque of the robot arm 82 to compensate for the force change caused by the displacement of the tool spindle 20 in the milling drill device 81.

[0086] Fifth, torque control and compensation: According to the joint compensation amount calculated by the inverse kinematics algorithm, the torque output of each joint motor of the robot arm 82 is controlled.

[0087] Sixth, based on the joint torque calculated by the force Jacobian matrix, the motor torque of the robot arm 82 is adjusted to keep the tool spindle 20 in a stable position during the cutting process; by adjusting the motor current of the robot arm 82 in real time, the motor torque is ensured to match the actual requirements of the end effector of the robot arm 82 to compensate for the error caused by the displacement of the tool spindle.

[0088] Seventh, feedback control loop: The current state of each joint of the robot arm 82 can be monitored and updated in real time through the feedback control loop, forming a closed-loop control system.

[0089] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it 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, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0090] Finally, it should be noted that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A milling drilling device, characterized in that: The milling drill device includes a sealed housing, a tool spindle, a wave spring, a brushless motor, and a drive unit provided with a three-layer circuit board; The tool spindle, the wave spring, the brushless motor and the drive unit are all arranged in the sealed housing; The tail of the tool spindle is fixedly connected to the rotor of the brushless motor, the head of the tool spindle is provided with a milling drill bit, and the tail of the rotor of the brushless motor is provided with a radial magnet; The wave spring is fixed between the tail of the tool spindle and the brushless motor; The driving unit is arranged at an end of the radial magnet away from the tail of the rotor, and a gap of a preset distance is arranged between the driving unit and the radial magnet; The first layer of the circuit board of the driving unit is used to obtain the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring; the second layer of the circuit board of the driving unit is used to use the rotation parameters and the expansion and contraction parameters to determine the control current of the brushless motor based on the relationship between the axial pressure of the tool spindle and the cutting force of the milling drill bit, and use the control current to control the brushless motor to drive the milling drill bit to move through the tool spindle; the third layer of the circuit board of the driving unit is used to provide a stabilized power supply for the driving unit.

2. The milling drilling device according to claim 1, characterized in that The first layer circuit board of the driving unit is integrated with a rotary Hall sensor and a linear Hall sensor; the second layer circuit board of the driving unit is integrated with three half H-bridge chips, a main control chip and a sampling module; the third layer circuit board of the driving unit is integrated with a power management chip, a voltage regulator chip and a filtering module.

3. The milling drilling device according to claim 2, characterized in that The sampling module includes at least two current sampling resistors; the filtering module includes at least two filtering capacitors.

4. The milling drilling device according to claim 1, characterized in that The three layers of circuit boards of the driving unit are connected to each other in communication via pin headers.

5. The milling drilling device according to claim 1, characterized in that Also includes a power supply unit; The power supply unit is fixed to an end of the driving unit away from the brushless motor; the power supply unit is arranged in the sealed housing.

6. The milling drilling device according to claim 1, characterized in that Also included is a saline tube; The physiological saline tube is fixed to the outside of the sealing shell along the direction of the tool spindle, and the tube mouth of the physiological saline tube is arranged at the milling drill bit; The saline tube is used to cool and clean the milling drill bit using saline.

7. The milling drilling device according to claim 5, characterized in that The power supply unit includes a battery.

8. A control method for a milling drilling device, characterized in that: The milling drilling device according to any one of claims 1 to 7 executes the control method, and the control method comprises: The first layer circuit board of the driving unit obtains the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring; The second circuit board of the driving unit determines the axial pressure of the tool spindle based on the telescopic parameter; The second circuit board determines the control current of the brushless motor using the rotation parameter based on the relationship between the axial pressure and the cutting force of the milling drill bit; The second layer circuit board uses the control current to control the brushless motor to drive the milling drill to move through the tool spindle based on a magnetic field oriented control algorithm.

9. The control method of the milling drilling equipment according to claim 8, characterized in that: The second layer circuit board uses the control current to control the brushless motor to drive the milling drill through the tool spindle based on the magnetic field oriented control algorithm, and the action includes: The second layer circuit board collects the current three-phase current of the brushless motor through a sampling module; The main control chip of the second layer circuit board performs Clarke transformation using the current three-phase current to obtain a two-phase static reference system current; The main control chip performs Park transformation using the two-phase stationary reference frame current to obtain a two-phase rotating reference frame current; The main control chip determines the two-phase rotating reference system voltage based on PI control using the two-phase rotating reference system current and the target current, wherein the target current is the control current; The main control chip uses the two-phase rotating reference frame voltage to perform an inverse Park transformation to obtain a two-phase stationary reference frame voltage; The main control chip uses the two-phase stationary reference frame voltage to perform Clarke inverse transformation to obtain a target three-phase voltage, and uses the target three-phase voltage to control the brushless motor to drive the milling drill to move through the tool spindle.

10. A robot, characterized in that: The robot comprises a mechanical arm and the milling drill equipment according to any one of claims 1 to 7; the milling drill equipment is arranged on the mechanical arm, and the mechanical arm drives the milling drill equipment to perform corresponding actions.

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