Milling drilling equipment and robot
By designing a milling drilling device that includes a sealed housing, tool spindle, wave spring, brushless motor and three-layer circuit board, and using a magnetic field-oriented control algorithm to regulate the brushless motor in real time, the problem of low control accuracy of existing equipment is solved, and high-precision and flexible motor control is achieved to adapt to complex brain surgery.
Patent Information
- Application Number
- CN202510066323.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-09-09
- Estimated Expiration
- 2045-01-16
AI Technical Summary
Existing milling drill equipment has low control accuracy in brain surgery and cannot dynamically adapt to different surgical needs.
A milling drill device was designed, which includes a sealed housing, a tool spindle, a wave spring, a brushless motor, and a drive unit with a three-layer circuit board. By acquiring the rotation parameters of the brushless motor and the expansion and contraction parameters of the wave spring in real time, the control current of the brushless motor was determined using a magnetic field oriented control algorithm, thereby achieving dynamic regulation of the motor.
The control accuracy of the milling drill equipment has been improved, which can dynamically adapt to different surgical needs, and the control accuracy and flexibility of the motor have been improved to meet the requirements of complex brain surgery.
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Figure CN119498924B_ABST
Abstract
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 and a robot. Background Art
[0002] Precise drilling and milling operations are crucial in brain surgery. However, existing surgical instruments often suffer from insufficient precision and an inability to dynamically adapt to different surgical needs. This limits their precise control and operational flexibility, making them unable to meet the requirements of complex brain surgery. Summary of the Invention
[0003] The embodiments of the present invention provide a milling drill device and a robot, which solve the technical problems in the prior art of low control accuracy of the milling drill device and the inability to dynamically adapt to different surgical requirements.
[0004] An embodiment of the present invention provides a milling drill device, which includes 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 provided between the driving unit and the radial magnet;
[0009] 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 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.
[0010] Furthermore, 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.
[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 the 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; and the power supply unit is arranged in the sealed housing.
[0015] Furthermore, it also includes a normal saline tube;
[0016] The physiological saline tube is fixed to the outside of the sealed housing 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 physiological saline tube is used to cool and clean the milling drill bit using physiological 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, wherein the milling drill device described in any of the above embodiments executes the control method, and the control method includes:
[0020] The first circuit board of the drive 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 bit 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 bit through the tool spindle based on the magnetic field oriented control algorithm, including:
[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 stationary reference frame 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 a two-phase rotating reference frame voltage using the two-phase rotating reference frame current and a target current based on PI control, wherein the target current is the control current;
[0029] The main control chip performs an inverse Park transform using the two-phase rotating reference frame voltage 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 robotic arm and the milling drill device described in any of the above embodiments; the milling drill device is arranged on the robotic arm, and the robotic arm drives the milling drill device to perform corresponding actions.
[0032] An embodiment of the present invention discloses a milling drill device 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 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 problem that the control accuracy of the milling drill equipment in the prior art is low and cannot dynamically adapt to different surgical requirements, and achieves the technical effect of being able to dynamically regulate the motor and improve the control accuracy of the motor. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Figure 1 This is an appearance diagram of a milling drilling device provided by an embodiment of the present invention;
[0034] Figure 2 This is a structural diagram of a milling drilling device provided by an embodiment of the present invention;
[0035] Figure 3 This 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 drive unit provided by an embodiment of the present invention;
[0037] Figure 5 is a detailed view 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 drive unit from another perspective provided by an embodiment of the present invention;
[0039] Figure 7 This is a flow chart of a control method for a milling drilling device provided by an embodiment of the present invention;
[0040] Figure 8 Schematic diagram of a surgical robot provided by an embodiment of the present invention. DETAILED DESCRIPTION
[0041] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.
[0042] It should be noted that the terms "first," "second," and so on, in the specification, claims, and drawings of the present invention are used to distinguish different objects, and are not intended to limit a specific order. The following embodiments of the present invention can be implemented independently or in combination with each other, and the present invention does not impose specific limitations on this.
[0043] Figure 1 This 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 This 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 provided at the 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 drive 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 drive unit 50 is used to use the rotation parameters and 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 drive unit 50 is used to provide a stabilized power supply for the drive 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 by 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 generate 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 device can be used by hand or be set on a robotic arm and used by robot control. When the milling drill device 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 will apply 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 will detect the rotation parameters of the brushless motor 40 and the expansion and contraction parameters of the wave spring 30, wherein the rotation parameters include at least the current speed and current torque of the brushless motor 40, and the expansion and contraction parameters include at least 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 obtained 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 based on 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 and 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, if 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 and 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 problem that the control accuracy of the milling drill equipment in the prior art is low and cannot dynamically adapt to different surgical requirements, and achieves the technical effect of being able to dynamically regulate the motor and improve the control accuracy of the motor.
[0050] Figure 4 This is a structural diagram of a driving unit provided by an embodiment of the present invention. Figure 5 This is a detailed view of a driving unit under a viewing angle provided by an embodiment of the present invention. Figure 6 This is a detailed view of the driving unit from another perspective provided by an embodiment of the present invention.
[0051] Alternatively, as Figure 4-6 As shown, the first-layer circuit board 51 of the driving unit 50 is integrated with a rotary Hall sensor 511 and a linear Hall sensor 512; the second-layer circuit board 52 of the driving unit 50 is integrated with three half-H bridge chips 521, a main control chip 522 and a sampling module 523; the third-layer circuit board 53 of the driving unit 50 is integrated with a power management chip 531, a voltage regulator chip 532 and a filtering module 533.
[0052] In an alternative embodiment, Figure 5-6 As shown, the sampling module 523 includes at least two current sampling resistors; the filtering module 533 includes at least two filtering capacitors.
[0053] Alternatively, as Figure 4-6 As shown, the three layers of the circuit board of the driving unit 50 are connected to each other through the pin header 54 to achieve communication.
[0054] Specifically, attend Figure 4-6The first circuit board 51 is equipped with a rotary Hall effect sensor 511, a linear Hall effect sensor 512, and other electrical components. The second circuit board 52 is equipped with a main control chip 522, three half-H-bridge chips 521, two current sampling resistors (i.e., the aforementioned sampling module 523), and other electrical components. Each of the three half-H-bridge chips 521 has two MOS transistors, forming a three-phase inverter circuit with six MOS transistors. The third circuit board 53 is equipped with a power management chip 531, a voltage regulator chip 532, two filter capacitors (i.e., the aforementioned filter module 533), and other electrical components. The second circuit board 52 uses the Field Oriented Control (FOC) algorithm to achieve efficient control of the brushless motor 40. The FOC algorithm specifically includes the Clarke transform and its inverse transform, the Park transform and its inverse transform, ensuring that the brushless motor 40 operates accurately and adapts to different surgical requirements. The third circuit board 53 also provides a regulated power supply for the drive unit 50. The filter module 533 located on it processes the control signal, making it more stable.
[0055] Alternatively, as 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 power. A battery is provided in the power supply unit 70 so that the milling drill device can continue to work without an external power supply.
[0057] Alternatively, as Figure 1 As shown, a saline tube 80 is also included; 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, achieving real-time and precise control of the brushless motor, 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 allows for dynamic adaptation to different surgical requirements, improves surgical flexibility, and meets the needs of complex brain surgery.
[0063] Figure 7 This is a flow chart of a control method for milling drilling equipment provided by an embodiment of the present invention.
[0064] The milling drill device in any of the above embodiments executes the control method, such as Figure 7 As shown, the control method of the milling drill equipment specifically includes the following steps:
[0065] S701 , the first 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 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. A rotational Hall effect sensor 511 and a linear Hall effect sensor 512 provided on the first 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 Newton-meters (N·m); K tis the torque constant of the brushless motor, in Newton-meters / ampere; I is the current of the brushless motor, in amperes.
[0071] In order to keep the brushless motor 40 at a certain speed, the axial pressure F axial The change of the brushless motor 40 dynamically adjusts the control current I, thereby controlling 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 and cutting force F cut The relationship between can be obtained through experiments. Specifically, the experiment can be carried out based on the similar material of the target to be cut. The similar material is placed on the six-dimensional force sensor, and the axial pressure F when cutting the material is determined by the six-dimensional force sensor through experiments. axial and cutting force F cut and establish the functional relationship F cut =f(F axial ). Then according to the calculation formula of motor torque: The control current I0 of the brushless motor is obtained thereby.
[0072] S704 , the second layer circuit board 52 controls the brushless motor 40 to drive the milling drill 21 to move via the tool spindle 20 using the control current based on the field oriented control algorithm (FOC algorithm).
[0073] Optionally, in step 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 layer circuit board 52 uses the current three-phase current i a 、i b 、i c Perform Clarke transform to obtain the two-phase stationary reference frame current i α 、i β The main control chip 522 uses the two-phase static reference system current i α 、i β Perform Park transform to obtain the two-phase rotating reference frame current i d 、i qThe main control chip 522 uses the two-phase rotating reference frame 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 voltage V d 、V q Perform inverse Park transform to obtain the two-phase static reference voltage V α 、V β The main control chip 522 uses the two-phase static reference voltage V α 、V β Perform Clark inverse transform 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: Among them, i a 、i b 、i c They are the three-phase currents of the brushless motor, i α 、i β They are the two-phase static reference system currents, and after Clarke transformation, the current components i α 、i β It is equivalent to the three-phase current i a 、i b 、i c Projecting in an orthogonal coordinate system can simplify the calculation. Similarly, the Clarke inverse transform is used to convert the two-phase stationary reference frame voltage V α 、V β Convert back to the target three-phase voltage V a 、V b 、V c , the formula is:
[0076] Park transform is to transform the two-phase stationary reference frame current i α 、i β Converted to two-phase rotating reference frame current i d 、i q A mathematical transformation of , whose formula is: Here, θ is the brushless motor's rotor angle, the aforementioned rotational parameter, acquired by the rotating Hall sensor. The Park transform converts the current in a stationary reference frame to a reference frame that rotates synchronously with the rotor, enabling vector control of the motor. Similarly, the inverse Park transform converts the voltage in a rotating reference frame back to the voltage in a stationary reference frame. The formula is:
[0077] Based on PI control, the two-phase rotating reference frame 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: V d =J p (i d0 -i d )+K i ∫(i d0 -i d )dt,V q =K p (i q0 -i q )+K i ∫(i q0 -i q )dt, 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 MOSFET is turned on and off by a PWM (Pulse Width Modulation) signal to adjust the voltage of the brushless motor 40. The MOSFET is a component of the 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 robotic arm and the milling drill device in any of the above embodiments; the milling drill device is arranged on the robotic arm, and the robotic 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 8As shown, the milling drill 81 is mounted on a robotic arm 82, which drives the milling drill 81 to perform corresponding actions. The robotic arm 82 uses forward and inverse kinematics algorithms, as well as the application of the force Jacobian matrix, to monitor and compensate for position errors of the robotic arm 82's end effector (i.e., the milling drill 81) in real time, ensuring that the tool spindle of the milling drill 81 maintains a stable position during the cutting process.
[0081] Specifically, the principle of the position compensation algorithm for 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 is calculated based on the position error. Based on the position error, an inverse kinematics algorithm is used to calculate the compensation for each joint of the robotic arm 82. The inverse kinematics algorithm converts the position error into angle compensation for each joint, ensuring that the end effector of the robotic 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 those on the tool spindle) into joint forces and torques. The force Jacobian matrix defines the relationship between changes in the end effector position and changes in the torques of each joint. The joint torques calculated using the force Jacobian matrix are used to dynamically adjust the motor torque of the robotic arm 82 to compensate for the force changes caused by the displacement of the tool spindle 20 in the milling drill 81.
[0086] Fifth, torque control and compensation: The torque output of each joint motor of the robotic arm 82 is controlled based on the joint compensation amount calculated by the inverse kinematics algorithm.
[0087] Sixth, the motor torque of the robot arm 82 is adjusted based on the joint torque calculated by the force Jacobian matrix so that the tool spindle 20 maintains 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, compensating for the error caused by the displacement of the tool spindle.
[0088] Seventh, the feedback control loop: The feedback control loop can monitor and update the current status of each joint of the robotic arm 82 in real time, forming a closed-loop control system.
[0089] In the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.
[0090] Finally, it should be noted that the above are only preferred embodiments of the present invention and the technical principles employed. 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 detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. 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 tool spindle is fixed to the inside of the sealed housing through bearings on both sides. The head of the tool spindle is provided with a milling drill bit. 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 wave spring is installed between the bearing for fixing the tail of the tool spindle and the end surface of the sealing housing; 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 provided between the driving unit and the 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 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.
2. The milling drilling device according to claim 1, characterized in that The first layer circuit board of the drive unit is integrated with a rotary Hall sensor and a linear Hall sensor; the second layer circuit board of the drive unit is integrated with three half-H bridge chips, a main control chip and a sampling module; the third layer circuit board of the drive 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 the circuit boards of the driving unit are connected to each other 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; and 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 sealed housing along the direction of the tool spindle, and the tube mouth of the physiological saline tube is arranged at the milling drill bit; The physiological saline tube is used to cool and clean the milling drill bit using physiological saline.
7. The milling drilling device according to claim 5, characterized in that The power supply unit includes a battery.
8. A robot, characterized in that: The robot includes a robotic arm and the milling drill device according to any one of claims 1 to 7; the milling drill device is arranged on the robotic arm, and the robotic arm drives the milling drill device to perform corresponding actions.
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