A driving circuit of a direct current brush motor for a passive-active rehabilitation training instrument

Abstract

The application discloses a driving circuit of a direct current brush motor for an active-passive rehabilitation training instrument, which comprises a power supply and conversion unit, a main controller unit, a network communication and sensing feedback unit, a power driving unit and a function interface unit. The power supply and conversion unit provides system power and converts voltage, and an output end is connected with power supply nodes of each unit. The main controller unit is in communication connection with the remaining units, coordinates output of the power driving unit and monitoring data of the network communication and sensing feedback unit to realize closed-loop control. The network communication and sensing feedback unit is connected with the main controller through an RS232 serial port, collects and transmits motor operation data in real time. The power driving unit converts digital control signals output by the main controller into PWM driving signals to control motor movement. The function interface unit is used for expanding system IO interfaces. The circuit is simple, has high control precision and stability, and has significantly enhanced driving and communication capacity.

Description

Technical Field

[0001] This application belongs to the field of DC brushed motor drive technology, specifically relating to a drive circuit for a DC brushed motor used in an active and passive rehabilitation training device. Background Technology

[0002] In active and passive rehabilitation training devices, sensors are key components ensuring their normal operation. To monitor the system's motion status in real time, such as position, speed, and direction, various sensors are typically installed, including magnetic encoders, absolute encoders, and photoelectric open-loop sensors. However, the increased number of sensors brings challenges to data transmission and processing. Data generated by numerous sensors needs to be exchanged and transmitted with the main control system in real time, placing extremely high demands on the system's computing power. To meet the demands of real-time processing of large amounts of data, the main control system needs to be equipped with a more powerful processor and a more complex hardware architecture. This not only directly increases the overall system cost but may also lead to increased power consumption and heat dissipation requirements, further enhancing the system's complexity and maintenance costs.

[0003] Meanwhile, active and passive rehabilitation training devices also have strict requirements for motor drives. As a power source, the motor's driving capability, speed control precision, and control stability directly affect the rehabilitation training effect and safety. During rehabilitation training, it is necessary to precisely control the motor speed and output torque according to the patient's different conditions and rehabilitation stages to achieve personalized rehabilitation plans. This requires the drive circuit system to have excellent driving capability, providing stable and sufficient power to the motor; high-precision speed control capability, ensuring that the motor speed accurately follows the preset command; and high control stability, avoiding minor fluctuations or malfunctions from causing adverse effects on the patient.

[0004] Currently available drive circuit systems have significant shortcomings in the aforementioned performance aspects. Their driving capabilities often fail to meet the demands of high-end rehabilitation training devices, exhibiting insufficient speed control precision with substantial errors, making accurate speed adjustment impossible. Furthermore, their control stability is poor, making them susceptible to external interference, leading to motor instability, vibration, and speed fluctuations. In addition, high-end drive systems largely rely on foreign manufacturers. This not only keeps product prices high, increasing production costs for rehabilitation training devices and driving up final product prices, thus limiting market penetration, but also results in limitations in after-sales service and technical support from foreign manufacturers, leading to high maintenance costs and long repair cycles, causing significant inconvenience to users.

[0005] Therefore, in the field of rehabilitation exercise, there is an urgent need for a high-performance, stable and reliable drive system to solve the problems of high data processing pressure of the main control system and insufficient performance of the drive circuit in the existing technology, to meet the high requirements of active and passive rehabilitation training instruments for motor drive, and to promote the development and application of rehabilitation training instrument technology. Utility Model Content

[0006] This application aims to provide a drive circuit for a DC brushed motor in an active and passive rehabilitation training device, which drives the DC brushed motor of the active and passive rehabilitation training device and exchanges and communicates with it. The drive circuit has the advantages of excellent driving performance, high control precision, simple circuit, wide range of applications, low cost and high reliability.

[0007] To achieve the above technical objectives, this application mainly adopts the following technical solutions:

[0008] In one aspect of this application, a drive circuit for a DC brushed motor in an active and passive rehabilitation training device is provided, comprising: a power supply and conversion unit, a main controller unit, a network communication and sensing feedback unit, a power drive unit, and a functional interface unit. The power supply and conversion unit is used to provide the system operating power and perform voltage conversion. The main controller unit is communicatively connected to the network communication and sensing feedback unit, the power drive unit, and the functional interface unit, respectively.

[0009] The network communication and sensing feedback unit is connected to the main controller unit via an RS232 serial port, used to collect motor operation data in real time and transmit it to the main controller unit; the power drive unit is connected to the main controller unit, used to convert the digital control signal output by the main controller unit into a PWM drive signal to control the movement of the DC brushed motor; the functional interface unit is connected to the main controller unit, used to expand the system I / O interface.

[0010] The output of the power supply and conversion unit is connected to the power supply nodes of each unit, and the main controller unit achieves closed-loop control by coordinating the output of the power drive unit with the monitoring data of the network communication and sensing feedback unit.

[0011] In one embodiment, the power supply and conversion unit includes a power input module and a voltage conversion module. The power input module is used to receive voltage. The voltage conversion module includes voltage conversion chips U1, U2, U3, and U4. The input of voltage conversion chip U1 is connected to the output of the power input module, converting the received 4.5V to 55V input voltage into a 5.5V intermediate voltage. The input of voltage conversion chip U2 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 12V output voltage. The input of voltage conversion chip U3 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 5V output voltage. The input of voltage conversion chip U4 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 3.3V output voltage. The 12V, 5V, and 3.3V output voltages are used to drive independent functional modules with different voltage requirements in the circuit system.

[0012] In one implementation, the main controller unit uses a control chip U5; the network communication and sensing feedback unit is connected to the control chip U5 via a 16-bit data bus, and the power drive unit is connected to the control chip U5 via an I / O port.

[0013] In one implementation, the main controller unit further includes:

[0014] Configuration interface J1 is coupled to the programming pin of control chip U5 and is used to program the control program to control chip U5.

[0015] Crystal oscillator Y1 is coupled to the oscillator input terminal of control chip U5, providing a reference clock frequency for control chip U5;

[0016] The buzzer LS1 is controlled by the I / O pins of the control chip U5 and is used to generate acoustic warning or operation prompt signals.

[0017] LED indicators D5 and D6 are respectively coupled to the I / O pins of the control chip U5 and are used to indicate the system status through optical signals.

[0018] In one implementation, the network communication and sensing feedback unit includes:

[0019] The magnetic encoder chip U9 is coupled to the motor output terminal of the power drive unit and is used to generate digital signals of motor speed and position based on the position detection of the servo motor rotor magnetic field.

[0020] The RS232 serial communication chip U12 establishes a data communication link with the control chip of the main controller unit through the UART protocol;

[0021] The CAN communication chip U13 establishes a data communication link with the control chip of the main controller unit through the CAN bus protocol;

[0022] Optical couplers U10 and U11 have their input terminals coupled to the digital I / O pins of the control chip of the main controller unit, and their output terminals coupled to external signal nodes. Electrical isolation and noise suppression between the input and output terminals are achieved through an optical coupling mechanism.

[0023] In one embodiment, the power drive unit includes:

[0024] Gate driver chips U6 and U7 have their input terminals coupled to the control signal output terminal of the main controller unit via an isolated communication interface, and are used to convert low-voltage control signals into high-voltage drive signals.

[0025] MOSFETs Q3, Q4, Q5, and Q6 have their gates coupled to the output terminals of gate driver chips U6 and U7, respectively, and their drains and sources form an H-bridge power topology.

[0026] The gate driver chips U6 and U7 suppress the interference of high-power circuit noise on the control signal through an electrical isolation mechanism; the H-bridge power topology adjusts the direction and amplitude of the output current by controlling the conduction sequence of MOSFETs Q3, Q4, Q5 and Q6, so as to realize the forward and reverse rotation and speed control of the DC brushed motor.

[0027] In one embodiment, the power drive unit further includes a current sensing amplifier U8, whose input is coupled to the current output path of the H-bridge power topology, converting the analog current signal into a digital signal, and whose output is communicatively connected to the main controller unit, which adjusts the PWM output duty cycle in real time based on the digital signal.

[0028] In one implementation, the functional interface unit includes:

[0029] Motor interface J2 is coupled to the power drive unit for connecting an external DC brushed motor;

[0030] The power input interface J3 is coupled to the high-voltage input terminal of the power supply and conversion unit and is used to connect to a DC input power supply.

[0031] The emergency power-off isolation interface J4 is connected to the main controller unit via an optocoupler isolation circuit and is used to receive external safety shutdown signals.

[0032] RS232 bus interface J5 is used for communication connection with the RS232 serial communication chip of the network communication and sensing feedback unit.

[0033] The dual-channel CAN bus interface J6 is used for communication connection with the CAN communication chip of the network communication and sensing feedback unit.

[0034] The beneficial effects of this application are as follows:

[0035] 1) The circuit of this application is simple, the control precision is high, and the control stability is good. Compared with the previous drive system, the driving capability and communication capability are significantly enhanced.

[0036] 2) An optocoupler circuit design is adopted to isolate and transmit electrical signals. Electrical isolation is achieved between the input and output through optical coupling, which helps to provide electrical isolation and noise suppression, thereby enhancing the stability and security of the system.

[0037] 3) A voltage protection circuit was designed to prevent instantaneous voltage from exceeding the normal operating voltage of the circuit, and at the same time, to reduce abnormal high voltage to a safe level, thereby preventing the protected devices or equipment from being damaged and improving the safety of the equipment. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the implementation module of the driving circuit in an embodiment of this application;

[0039] Figure 2 This is a circuit diagram of the power input according to an embodiment of this application;

[0040] Figure 3 This is a schematic diagram of the conversion circuit of the voltage conversion chip U1 in an embodiment of this application;

[0041] Figure 4 This is a schematic diagram of the conversion circuit of the voltage conversion chip U2 in an embodiment of this application;

[0042] Figure 5 This is a schematic diagram of the conversion circuit of the voltage conversion chip U3 in an embodiment of this application;

[0043] Figure 6 This is a schematic diagram of the conversion circuit of the voltage conversion chip U4 in an embodiment of this application;

[0044] Figure 7 This is a schematic diagram of the structure of the control chip U5 in an embodiment of this application;

[0045] Figure 8 This is a circuit diagram of the crystal oscillator Y1 in an embodiment of this application;

[0046] Figure 9 This is a schematic diagram of the power supply filtering circuit of the control chip U5 in an embodiment of this application;

[0047] Figure 10 This is a circuit diagram of the buzzer in an embodiment of this application;

[0048] Figure 11 This is a circuit diagram of an LED indicator light according to an embodiment of this application;

[0049] Figure 12 This is a circuit diagram of the program programming interface according to an embodiment of this application;

[0050] Figure 13 This is a circuit diagram of the magnetic encoder chip U9 in an embodiment of this application;

[0051] Figure 14 This is a circuit diagram of the serial communication chip U12 in an embodiment of this application;

[0052] Figure 15 This is a circuit diagram of the high-speed optocoupler chip U10 in an embodiment of this application;

[0053] Figure 16 This is a circuit diagram of the high-speed optocoupler chip U11 in an embodiment of this application;

[0054] Figure 17 This is a circuit diagram of the CAN communication chip U13 in an embodiment of this application;

[0055] Figure 18 This is a circuit diagram of the gate driver chip U6 in an embodiment of this application;

[0056] Figure 19 This is a circuit diagram of the gate driver chip U7 in an embodiment of this application;

[0057] Figure 20 This is a schematic diagram of the filtering and protection circuit for the +36V power supply in an embodiment of this application;

[0058] Figure 21 This is a circuit diagram of the current sensing amplifier chip U8 in an embodiment of this application. Detailed Implementation

[0059] The technical solution of this application will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are only some embodiments of this application, not all embodiments, and are only used to illustrate this application, and should not be regarded as limiting the scope of this application. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0060] like Figure 1 As shown, this application provides a drive circuit system for a DC brushed motor used in an active and passive rehabilitation training device, including a power supply and conversion unit, a main controller unit, a network communication and sensor feedback unit, a power drive unit, and a functional interface unit.

[0061] The power supply and conversion unit's input terminal is connected to an external power source, and its output terminal is electrically connected via a voltage conversion circuit to: the power input pin of the main controller unit, the power input interface of the network communication and sensing feedback unit, the power input terminal of the power drive unit, and the power supply port of the functional interface unit. The main controller unit has a built-in microcontroller, and its communication interface is connected to: the CAN bus interface and RS232 serial port of the network communication and sensing feedback unit, forming a bidirectional data channel; the control signal input terminal of the power drive unit, which outputs a PWM drive signal; and the expansion communication port of the functional interface unit, enabling external function expansion. The power input terminal of the power drive unit is connected to the high-voltage output terminal of the power supply and conversion unit, the control signal input terminal is connected to the PWM output pin of the main controller unit, and the power output terminal is connected to the winding terminals of the DC brushed motor. The functional interface unit has several signal input ports for connecting external sensors or emergency switches.

[0062] The power supply and conversion unit includes a current input module and a voltage conversion module. For example... Figure 2 As shown, the power input module includes diodes D1 and D2, and capacitors C1 to C7. Diodes D1 and D2 are connected in series to the positive terminal of the 36V DC input power supply. Specifically, the anode of D1 is directly electrically connected to the positive terminal (36V) of the input power supply, forming a primary protection node. The cathode of D1 and the anode of D2 form a series relay node through conductive traces. The cathode of D2 serves as the protected power output terminal (36V), forming a secondary protection node. Capacitors C1 to C7 are connected in parallel to form a distributed power filter network, arranged on the output side of the protection diodes (D1 and D2). The positive terminals of capacitors C1 to C7 are connected to the cathodes of D1 and D2, and the negative terminals of capacitors C1 to C7 are connected to the ground terminal. Through the secondary protection and the distributed filter capacitor network, polarity protection, surge suppression, and noise filtering of the input power supply are achieved.

[0063] like Figures 3-6 As shown, the voltage conversion module includes voltage conversion chips U1, U2, U3 and U4, capacitors C8 to C33, resistors R1 to R6, diodes D1 to D4, and filter inductors L1 and L2.

[0064] like Figure 3As shown, voltage conversion chip U1 is used to convert the voltage at the output node (36V_IN) of the current input module into a stable 5.5V output voltage. The specific connections of voltage conversion chip U1 are as follows: Pin 5 (VIN) is connected to the input voltage source 36V_IN and grounded through capacitor C8 for input voltage filtering. Pin 4 (EN) is connected to the input voltage source 36V_IN through resistor R1 and grounded for chip enable control. Pin 2 (GND) is directly grounded, providing the chip's reference ground. Pin 6 (SW) is connected to the anode of inductor L1, diode D3, and one end of capacitor C9 for switching the output. Pin 1 (BST) is connected to pin 6 (SW) through resistor R2 for driving the internal MOSFET. Pin 3 (FB) is connected to a voltage divider circuit composed of resistors R3 and R4 for feedback control of output voltage stability. The input voltage source 36V_IN is grounded through capacitor C8, which acts as a filter capacitor to remove high-frequency noise from the input voltage. Resistor R1 is connected between the input voltage source 36V_IN and pin 4 (EN) of chip U1, with pin 4 also grounded, for configuring the chip's enable control. Pin 6 (SW) is connected to one end of inductor L1, and the other end of inductor L1 is connected to the output voltage terminal 5.5V, and grounded through parallel capacitors C10 to C13, for filtering the output voltage. The anode of diode D3 is connected to pin 6 (SW), and the cathode is connected to the output voltage terminal 5.5V, acting as a power supply protection diode to prevent reverse voltage. Resistors R3 and R4 form a voltage divider circuit, connected between the output voltage terminal 5.5V and ground, with the divider point connected to pin 3 (FB), for feedback control of output voltage stability. Resistor R4 has a resistance of 21K, used to set the specific value of the output voltage.

[0065] like Figure 4 As shown, the input of voltage conversion chip U2 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage to a 12V output voltage. Specifically, the VIN pin of voltage conversion chip U2 (LM27313) is connected to the 5.5V output node of voltage conversion chip U1, the SW pin is connected to the second terminal of filter inductor L2 and the anode of rectifier diode D4, the first terminal of filter inductor L2 is connected to the 5.5V input node, the cathode of rectifier diode D4 is connected to the 12V output node, the input filter capacitor group C20~C23 is connected in parallel between the input node and ground, the output filter capacitor group C15~C18 is connected in parallel between the 12V output node and ground, the output voltage configuration resistor R5 is connected to the 12V output node and the FB pin of voltage conversion chip U2, the feedback filter capacitor C19 is connected to the FB pin and ground, and the shutdown pin SHDN is configured to a floating enabled state. This circuit realizes the 5.5V to 12V voltage conversion through a boost topology and integrates multi-stage filtering and precise voltage regulation functions.

[0066] like Figure 5 As shown, the input of voltage conversion chip U3 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 5V output voltage. The IN pin of voltage conversion chip U3 is connected to the output terminal of voltage conversion chip U1 (i.e., the node providing the 5.5V intermediate voltage), and one end of capacitors C24 and C25 is connected in parallel. The other ends of capacitors C24 and C25 are grounded. Capacitors C24 and C25 are connected in parallel between pin 1 (VIN) of chip U3 and ground, forming a filter circuit for the input power supply. This circuit filters out high-frequency interference signals from the 5.5V voltage input to voltage conversion chip U3, ensuring the purity of the input voltage. Pin 3 (EN) is connected to pin 1 (VIN) to enable voltage conversion chip U3, meaning the chip starts working when there is an input voltage. Pin 2 (GND): directly grounded to provide a reference ground potential for the chip. Pin 5 (VOUT) serves as the output voltage pin, outputting a 5V voltage. It is connected in parallel with one end of capacitors C26, C27, and C28, and the other end of capacitors C26, C27, and C28 is grounded. Capacitors C26, C27, and C28 are connected in parallel between pin 5 (VOUT) of the voltage conversion chip U3 and ground, forming a +5V power supply filter circuit to further filter out high-frequency noise in the output voltage, making the output 5V voltage more stable and smooth.

[0067] like Figure 6 As shown, the input of voltage conversion chip U4 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage to a 3.3V output voltage. Pin 1 (VIN) of voltage conversion chip U4 serves as the input voltage pin, connected to the output of voltage conversion chip U1, receiving the 5.5V intermediate voltage. Simultaneously, capacitors C29 and C30 are connected in parallel between pin 1 (VIN) and ground, forming an input power supply filter circuit to filter the input 5.5V voltage, removing high-frequency noise and ensuring input voltage stability. Pin 3 (EN) is the enable pin; no additional connection is shown in this circuit, and the chip is enabled by default, meaning it starts working when there is an input voltage. Pin 2 (GND) is grounded to provide a reference ground potential for the chip, ensuring the normal operating reference of the circuit. Pin 5 (VOUT) serves as the output voltage pin, outputting a 3.3V voltage. Capacitors C31, C32, and C33 are connected in parallel between pin 5 (VOUT) and ground, forming a filter circuit for the +3.3V power supply. This circuit filters out high-frequency interference signals in the output voltage, making the output 3.3V voltage more stable and pure. Pin 4 (ADJ) is left floating and is not connected to other circuit components in this circuit. The chip's internal output voltage is set to 3.3V, requiring no external adjustment.

[0068] like Figures 7-12As shown, the main controller unit consists of a control chip U5, a configuration interface J1, a crystal oscillator Y1, a buzzer LS1, light-emitting diodes D5 and D6, resistors R7 to R15, capacitors C34 to C43, and a transistor Q1.

[0069] Specifically, pin 1 of crystal oscillator Y1 is connected to pin 5 of control chip U5, transmitting the oscillation input signal generated by crystal oscillator Y1 to control chip U5 as one of the input sources of clock signal for control chip U5. Pin 3 of crystal oscillator Y1 is connected to pin 6 of control chip U5, and the oscillation signal output by crystal oscillator Y1 further interacts with control chip U5 to ensure that control chip U5 can obtain a stable and accurate oscillation signal to maintain normal working rhythm.

[0070] Pins 4 and 2 of crystal oscillator Y1 are connected to pins 8, 23, 35, and 47 of control chip U5 to ground, providing a unified reference ground potential for both crystal oscillator Y1 and control chip U5. This ensures electrical stability and avoids signal interference or malfunctions caused by potential differences. One end of capacitor C38 is connected to pin 1 of crystal oscillator Y1, and the other end is grounded; one end of capacitor C39 is connected to pin 3 of crystal oscillator Y1, and the other end is grounded. Capacitors C38 and C39 act as load capacitors, assisting crystal oscillator Y1 in stabilizing its oscillation frequency, ensuring that crystal oscillator Y1 can oscillate accurately at its nominal frequency, and providing a stable and accurate clock signal for control chip U5. The control chip U5 has multiple power supply pins for receiving a +3.3V power supply. Capacitors C40, C41, C42, and C43 are connected in parallel between the +3.3V power supply line of the control chip U5 and ground to filter out high-frequency noise and ripple in the +3.3V power supply, providing a more stable and clean +3.3V power supply for the control chip U5 and ensuring that the chip can operate reliably.

[0071] Resistors R12 and R13 are connected in series with LEDs D5 and D6, respectively, forming two independent LED indicator circuits to indicate different operating states of the main controller unit. Both LED indicator circuits are connected to a +3.3V power supply and to the control chip U5 via corresponding pins. Specifically, LED D5 is a green LED, with its anode connected to the +3.3V power supply. Resistor R12 is connected in series between the cathode of LED D5 and pin 25 of the control chip U5, limiting the current flowing through LED D5 to prevent damage from excessive current. When the control chip U5 outputs a specific level signal at pin 25, it controls whether current flows through LED D5, thus controlling the indicator light's on / off state. LED D6 is a red LED, with its anode also connected to the +3.3V power supply. Resistor R13 is connected in series between the cathode of LED D6 and pin 26 of the control chip U5, limiting the current flowing through LED D6 to protect it from damage by excessive current. By outputting different level signals at pin 26, the control chip U5 can determine whether current flows through the LED D6, thereby controlling the indicator light's on / off state.

[0072] The buzzer's operating state is controlled by the signal output from pin 46 of control chip U5. Capacitor C35 is connected between the 5V power supply and ground, with one end connected to the 5V power supply and the other to ground. It filters out high-frequency noise from the 5V power supply, providing a stable power supply to the buzzer and preventing power supply noise from interfering with its operation. Resistor R10 is connected in series between the collector of transistor Q1 and pin 46 of control chip U5, limiting the current flowing into the buzzer. It also works with other components in the circuit to configure the operating state of transistor Q1, ensuring that the transistor can correctly conduct and cut off, thereby controlling the buzzer's on / off state. Resistor R11 is connected between the base of transistor Q1 and ground, providing a stable bias voltage to the base of transistor Q1. Together with the signal input from pin 46 of control chip U5, it controls the base current of transistor Q1, thus controlling the transistor's conduction level and amplifying and controlling the buzzer current. Transistor Q1 acts as a current amplifier, with its emitter grounded and its collector connected to buzzer LS1. Its base is connected to pin 46 of control chip U5 via a signal line. When pin 46 outputs a high level, the base of transistor Q1 receives sufficient current to conduct, allowing the 5V power supply to form a circuit through buzzer LS1, energizing the buzzer and causing it to sound. When pin 46 outputs a low level, transistor Q1 is cut off, and the buzzer stops sounding.

[0073] Interface J1 serves as the programming interface for programming the microcontroller U5. Pin 4 of interface J1 is connected to signal line SWDIO (PA13), which transmits serial wire data input / output signals. In the control chip U5, the SWDIO (PA13) signal is connected to pin 34, thus establishing a data transmission channel between interface J1 and the control chip U5 for transmitting instructions and data during the programming process. Pin 3 of interface J1 is connected to signal line SWCLK (PA14), which transmits a serial wire clock signal. In the control chip U5, the SWCLK (PA14) signal is connected to pin 37, providing a clock synchronization signal for the programming process and ensuring accurate data transmission between interface J1 and the control chip U5. Pin 1 of interface J1 is connected to a 3.3V power supply to provide operating voltage for the interface circuit. Capacitor C37 is connected between the 3.3V power supply and ground, close to pin 1 of interface J1. Capacitor C37 acts as a filter capacitor to remove high-frequency noise from the 3.3V power supply, ensuring the stability of the interface circuit power supply and preventing power supply noise from interfering with the program burning process. Pin 2 of interface J1 is grounded to provide a stable reference ground potential for the entire interface circuit. Resistors R14 and R15 are connected in series between the 3.3V power supply and the SWDIO (PA13) and SWCLK (PA14) signal lines. This prevents excessive current from flowing into the pins of the control chip U5 and ensures that the signal level is within an appropriate range to guarantee the reliability of signal transmission.

[0074] like Figures 13-17 As shown, the network communication and sensing feedback unit consists of a magnetic encoder chip U9, a serial communication chip U12, a CAN communication chip U13, capacitors C56 to C63, resistors R29 to R39, diodes D10 to D13, and high-speed optocoupler chips U10 and U11.

[0075] The magnetic encoder chip U9 (TLE5012B-E1000) connects to the main control unit and functional interface unit via control I / O ports to achieve data transmission and control command interaction. Chip U9 has multiple pins, among which IFC, SCK, CSQ, and DATA pins are used for external communication and control. Pin 5 (CHA) is the output signal pin of the magnetic encoder chip U9, used to output encoder signals; pin 6 (VDD) is connected to a 3.3V power supply, providing the operating voltage for chip U9; pin 7 (GND) is grounded, providing a reference ground potential for the chip; pin 8 (CHB) is the output signal pin of the magnetic encoder chip U9, used to output encoder signals. Capacitor C57 is connected between the 3.3V power supply and ground, specifically with one end connected to the 3.3V power supply and the other end grounded. Its function is to filter the power supply of the magnetic encoder chip U9, removing high-frequency noise and ensuring a stable power supply for the chip. Resistor R29 is one of the configuration resistors of the magnetic encoder chip U9. One end of it is connected to the signal line output by pin 8 (CHB) of chip U9, and the other end is connected to signal line TIM3_CH2 (PA7). This resistor plays a role in signal matching, voltage division, or adjusting signal characteristics in the circuit to ensure that the signal output from pin CHA can be accurately and stably transmitted to subsequent circuits. One end of signal line TIM3_CH2 (PA7) is connected to pin 8 (CHB) of magnetic encoder chip U9 through resistor R29, and the other end is connected to pin 17 of control chip U5. Through this connection, the CHB signal output by magnetic encoder chip U9 can be transmitted to control chip U5. Control chip U5 can process and analyze the signal to obtain measurement information related to the magnetic encoder. Resistor R31 is also a configuration resistor. One end is connected to the signal line output by pin 5 (CHA) of chip U9, and the other end is connected to signal line TIM3_CH1 (PA6). It is used to configure the TIM3_CH1 (PA6) signal, such as signal termination matching and level adjustment, to ensure the integrity and stability of the signal during transmission. One end of signal line TIM3_CH1 (PA6) is configured through resistor R31, and the other end is connected to pin 16 of control chip U5. This signal is also used to transmit relevant information of the magnetic encoder to control chip U5. Together with the TIM3_CH2 (PA7) signal, it provides the control chip U5 with the measurement data of the magnetic encoder so that the control chip U5 can perform subsequent control and decision-making.

[0076] High-speed optocoupler chips U10 and U11 (both model TLP2362) are used to achieve isolated signal transmission. Specifically, optocoupler chip U10 has signal input lines marked CTL1+ and CTL1-, which are connected to both ends of resistor R30. Resistor R30 acts as an impedance matching resistor, limiting the current input to the high-speed optocoupler chip U10 and ensuring the stability and reliability of the input signal. Diode D10 is connected in parallel with resistor R30, presumably to prevent reverse voltage from the input signal from damaging the optocoupler chip, thus providing isolation and protection. The connection of resistor R30 allows the input signal to drive the input side of the high-speed optocoupler chip U10 with an appropriate level and current. Pin 1 is labeled A (anode) and pin 3 is labeled C (cathode), used for signal driving on the input side; pin 4 is labeled GND, pin 5 is labeled Vo (output voltage), and pin 6 is labeled Vcc, used for power supply and signal output on the output side; pins 1 and 3 on the input side are connected to the input signals CTL1+ and CTL1- through the aforementioned resistor R30 and diode D10, realizing the reception and processing of the input signal; capacitor C56 is connected between the 5V power supply and ground, specifically one end is connected to the 5V power supply and the other end is grounded, used to filter the power supply on the output side of the high-speed optocoupler chip U10, remove high-frequency noise in the power supply, and provide a stable power supply environment; one end of resistor R32 is connected to the 3.3V power supply, and the other end is connected to the output pin Vo (pin 5) of the optocoupler chip U10, as an input configuration resistor, possibly used to adjust the level or driving capability of the output signal; the output signal CTL1 (PB7) is led out from pin 5 of the optocoupler chip U10 and connected to pin 43 of the control chip U5, realizing the transmission of the isolated signal to the control chip.The optocoupler chip U11 is specifically designed as follows: Signal input lines are marked CTL2+ and CTL2-, respectively connected to the two ends of resistor R33. Resistor R33 also acts as an impedance matching resistor, limiting the current input to the high-speed optocoupler chip U11. Diode D11 is connected in parallel with resistor R33, providing isolation and protection to prevent damage to the optocoupler chip from reverse voltage of the input signal. The connection of resistor R33 ensures that the input signal can drive the input side of the high-speed optocoupler chip U11 in a suitable state. The pin functions of the high-speed optocoupler chip U11 are similar to those of U10: pin 1 is A (anode), pin 3 is C (cathode), used for signal driving on the input side; pin 4 is GND, pin 5 is Vo (output voltage), and pin 6 is Vcc, used for the output side. The power and signal outputs are handled by pins 1 and 3 on the input side, which are connected to the input signals CTL2+ and CTL2- via resistor R33 and diode D11 to receive and process the input signals. Capacitor C58 is connected between the 5V power supply and ground, with one end connected to the 5V power supply and the other end grounded, to filter the power supply on the output side of the high-speed optocoupler chip U11 and provide a stable power supply. Resistor R34 is connected to the 3.3V power supply at one end and to the output pin Vo (pin 5) of the optocoupler chip U11 at the other end, serving as an input configuration resistor to adjust the characteristics of the output signal. The output signal CTL2 (PB6) is led out from pin 5 of the optocoupler chip U11 and connected to pin 42 of the control chip U5 to transmit the isolated signal to the control chip.

[0077] The serial communication chip U12 (MAX3232IDR) is used to implement serial communication functions and has features such as power filtering and signal protection. Specifically, capacitors C59 and C63 serve as decoupling capacitors for the U12 serial communication chip, connected near the chip's power supply pins. One end of C59 is connected to pin 2 (V+) of the U12 serial communication chip, and the other end is grounded; one end of C63 is connected to pin 6 (V-) of the U12 serial communication chip, and the other end is grounded. The function of the decoupling capacitors is to filter out high-frequency noise on the power supply line and ensure the stability of the chip's power supply. Capacitors C61 and C62 serve as the charge pump boost capacitors for the serial communication chip U12, participating in the chip's internal charge pump circuit to provide sufficient voltage swing. C61 is connected between pin 1 (C1+) and pin 3 (C1-) of the U12 serial communication chip; C62 is connected between pin 4 (C2+) and pin 5 (C2-) of U12. These capacitors store and release charge in the charge pump circuit, achieving the voltage boost function. Resistors R35 and R36 serve as configuration resistors for the U12 serial communication chip, used to set the chip's operating parameters. R35 and R36 are connected in parallel between the 3.3V power supply and pins 10 and 9 of the U12 serial communication chip. Capacitor C60 serves as the input power filter capacitor for the U12 serial communication chip, connected between the 3.3V power supply and ground. One end of C60 is connected to the 3.3V power supply, and the other end is grounded, used to filter out low-frequency noise on the power line and provide a stable input power supply. Diodes D12 and D13 serve as signal protection diodes for the serial communication chip U12, connected to the serial signal lines respectively. The anodes of D12 and D13 are grounded, and their cathodes are connected to pins 13 (RIN1) and 8 (DOU2) of U12 respectively. This prevents overvoltage on the serial signal lines from damaging the chip. When a transient voltage higher than normal appears on the signal line, the diodes conduct, clamping the overvoltage to a safe level. Pins 10 (DIN2) and 9 (ROUT2) of the serial communication chip U12 correspond to pins 21 and 22 of the control chip U5 via signal lines USART3_TX (PB10) and USART3_RX (PB11) respectively. DIN2 is used to receive transmit signals from the control chip, and ROUT2 is used to send receive signals to the control chip.

[0078] The CAN communication chip U13 (TJA1051T / 3) is used to implement CAN bus communication functions and includes key connection components such as power filtering, signal transmission, and terminating resistors. Specifically, capacitor C64 serves as a power filter capacitor, with one end connected to the 5V power supply and the other end grounded. This capacitor filters out high-frequency noise on the 5V power line, providing a stable power input for the CAN communication chip U13 and ensuring its normal operation. The CAN_TX (PA12) signal line is connected to one end of resistor R37, and the other end of R37 is connected to pin 1 (TXD) of the CAN communication chip U13. CAN_TX (PA12) corresponds to pin 34 of the control chip U5 and is used to transmit the CAN transmit signal from the control chip to the CAN communication chip U13. The CAN_RX (PA11) signal line is connected to one end of resistor R39, and the other end of R39 is connected to pin 4 (RXD) of the CAN communication chip U13. CAN_RX (PA11) corresponds to pin 33 of the control chip U5 and is used to transmit the CAN signal received by the CAN communication chip U13 to the control chip. Pin 1 (TXD) is connected to the external CAN_TX (PA12) signal line via resistor R37 for signal transmission. Pin 4 (RXD) receives signals from the CAN bus, processes them internally, and then transmits them to the external CAN_RX (PA11) signal line via pin RXD, ultimately reaching the control chip. Resistor R38 is connected between CANH and CANL as the CAN bus terminating resistor. Its function is to prevent CAN bus signal reflection and ensure the stability and reliability of signal transmission. Pins 7 (CANH) and 6 (CANL) of the CAN communication chip U13 are respectively led out as the positive and negative signal lines of the CAN bus, used to connect other node devices in the CAN bus network.

[0079] like Figures 18-21 As shown, the power drive unit includes gate drive chips U6 and U7, current sensing amplifier U8, MOSFETs Q2, Q3, Q4, and Q5, capacitors C44 to C55, resistors R16 to R28, and diodes D7 to D9.

[0080] Specifically, the gate driver chip U6 consists of: Capacitor C44 connected between the 12V power supply and ground, serving as the power supply filter capacitor for U6 to filter out high-frequency noise on the power line and ensure a stable power supply for chip U6. Resistors R16 and R18 are configuration resistors for the gate driver chip U6. R16 is connected between the TIM1_CH3 (PA10) signal line and the input pin of U6, and R18 is connected between the TIM1_CH3N (PB15) signal line and another input pin of U6. TIM1_CH3 (PA10) and TIM1_CH3N (PB15) correspond to pins 31 and 28 of the control chip U5, respectively, and are used to set the input signal characteristics of chip U6, such as signal level and drive capability. Diode D7 is connected between the 12V power supply and the power supply pin of U6 to provide protection against reverse connection or transient voltage damage to the chip. The gates of MOSFETs Q2 and Q3 are connected to the output pins of the gate driver chip U6 via resistors R17 and R19, respectively. U6 controls the output signal to turn Q2 and Q3 on and off, thereby controlling the operation of motor A. The drain of Q2 is connected to a 36V power supply, and its source is connected to one end of motor A. The drain of Q3 is connected to the other end of motor A, and its source is grounded. Resistors R17 and R19 are connected between the output pin of U6 and the gates of MOSFETs Q2 and Q3 to adjust the rise and fall times of the gate drive signal, optimizing the switching characteristics of the MOSFETs. One end of capacitor C47 is connected to the VS pin (pin 6) of the gate driver chip U6 (IRS21867STRPBF), and the other end is grounded to filter out high-frequency noise on the VS pin.

[0081] Specifically, the gate driver chip U7 consists of: Capacitor C46 connected between the 12V power supply and ground, serving as the power supply filter capacitor for U7, filtering out high-frequency noise on the power line and providing a stable power supply for chip U7. Resistors R22 and R24 are configuration resistors for the gate driver chip U7. R22 is connected between the TIM1_CH2(PA9) signal line and the input pin of U7, and R24 is connected between the TIM1_CH2N(PB14) signal line and another input pin of U7. TIM1_CH2(PA9) and TIM1_CH2N(PB14) correspond to pins 30 and 27 of the control chip U5, respectively, and are used to set the input signal characteristics of chip U7. Diode D8 is connected between the 12V power supply and the power supply pin of U7, protecting chip U7 from reverse connection or transient voltage. The gates of MOSFETs Q4 and Q5 are connected to the output pins of the gate driver chip U7 via resistors R23 and R25, respectively. U7 controls the turn-on and turn-off of Q4 and Q5 by controlling the output signals, thereby controlling the operation of motor B (MOTOR_B). The drain of Q4 is connected to a 36V power supply, and its source is connected to one end of motor B; the drain of Q5 is connected to the other end of motor B, and its source is grounded. Furthermore, the current detection signal of motor B is divided by resistors R20 and R21, filtered by capacitor C48, and outputs CURRENT_P and CURRENT_N signals to monitor the operating current of motor B. Resistors R23 and R25 are connected between the output pins of U7 and the gates of MOSFETs Q4 and Q5 to adjust the rise and fall times of the gate drive signals, optimizing the switching performance of the MOSFETs. One end of capacitor C47 is connected to the VS pin (pin 6) of the gate driver chip U7 (IRS21867STRPBF), and the other end is grounded to filter out high-frequency noise on the VS pin.

[0082] The +36V power supply input is filtered and protected to ensure a stable and safe power supply for subsequent circuits. Specifically, capacitor C49 is a polarized capacitor, with its positive terminal connected to the +36V power input and its negative terminal grounded. It filters out low-frequency noise on the +36V power line and smooths out voltage fluctuations by storing and releasing charge, providing a relatively stable DC voltage for subsequent circuits. Capacitor C50 is also a polarized capacitor, with its positive terminal connected to the junction of the +36V power line and the positive terminal of capacitor C49, and its negative terminal grounded. C50 and C49 work together to further enhance the filtering effect on low-frequency noise and improve power supply stability. Capacitor C51 is a non-polarized capacitor, with its two ends connected between the +36V power line and ground, respectively. It filters out high-frequency noise on the power line. Due to its non-polarized nature, it can quickly respond to changes in high-frequency signals, effectively suppressing high-frequency interference and ensuring power purity. The anode of diode D9 is grounded, and the cathode is connected to the +36V power input terminal. As a protection diode, it prevents the reverse connection of the power supply from damaging the subsequent circuit. When the power supply is connected normally, diode D9 is in a reverse bias state and hardly conducts, so it does not affect the normal operation of the circuit. When the power supply is reversed, diode D9 conducts in the forward direction, clamping the voltage at a lower level, thereby protecting the subsequent circuit components from the impact of reverse voltage.

[0083] The circuit for the current sensing amplifier chip U8 is as follows: Capacitor C54 is the filter capacitor for the current sensing amplifier chip U8. One end of C54 is grounded, and the other end is connected to pins A1 and A2 of chip U8, respectively, to filter the input signal and reduce noise interference. Capacitors C52 and C53 are connected in parallel, with one end connected to power supply pins 6 and 7 of chip U8 and the other end grounded. They serve as filter capacitors for the power supply of the current sensing amplifier chip U8, used to stabilize the power supply voltage and filter out high-frequency noise in the power supply. Resistor R26 is connected in series between the power supply and capacitors C52 and C53 as a current-limiting resistor, limiting the current flowing into chip U8 and preventing excessive current from damaging the chip. One end of resistor R27 is connected to the output pin of chip U8, and the other end is connected to the subsequent circuit for transmitting the signal output by the chip. Resistor R28 and capacitor C55 are connected in parallel, with one end grounded and the other end connected to the connection point between resistor R27 and the subsequent circuit. Resistors R27 and R28 and capacitor C55 together constitute the configuration resistor and filter capacitor for the output signal of chip U8, which are used to adjust the parameters of the output signal (such as gain) and filter the output signal to ensure the stability and accuracy of the output signal.

[0084] The drive circuit described in this application boasts advantages such as simple circuitry, wide applicability, low cost, and high reliability. It employs an optocoupler circuit design and voltage protection circuitry to reliably isolate coupling between transmitted electrical signals and suppress noise. Simultaneously, it prevents transient voltages from exceeding the circuit's normal operating voltage and reduces abnormal high voltages to a safe level, thereby protecting the device or equipment from damage and ensuring equipment safety. It is highly suitable for various devices employing brushed DC motors and can be well-configured and applied in environments such as rehabilitation medical products and automated production lines.

[0085] In the above embodiments, the specific circuit can be replaced according to actual needs. The specific circuit of this application does not represent all embodiments of the technical solution of this application.

[0086] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A drive circuit for a DC brushed motor in an active and passive rehabilitation training device, characterized in that, include: The system includes a power supply and conversion unit, a main controller unit, a network communication and sensing feedback unit, a power drive unit, and a functional interface unit. The power supply and conversion unit provides the system operating power and performs voltage conversion. The main controller unit is communicatively connected to the network communication and sensing feedback unit, the power drive unit, and the functional interface unit. The network communication and sensing feedback unit is connected to the main controller unit via an RS232 serial port, used to collect motor operation data in real time and transmit it to the main controller unit; the power drive unit is connected to the main controller unit, used to convert the digital control signal output by the main controller unit into a PWM drive signal to control the movement of the DC brushed motor; the functional interface unit is connected to the main controller unit, used to expand the system I / O interface. The output of the power supply and conversion unit is connected to the power supply nodes of each unit, and the main controller unit achieves closed-loop control by coordinating the output of the power drive unit with the monitoring data of the network communication and sensing feedback unit.

2. The driving circuit according to claim 1, characterized in that, The power supply and conversion unit includes a power input module and a voltage conversion module. The power input module is used to receive voltage. The voltage conversion module includes voltage conversion chips U1, U2, U3, and U4. The input of voltage conversion chip U1 is connected to the output of the power input module, converting the received 4.5V to 55V input voltage into a 5.5V intermediate voltage. The input of voltage conversion chip U2 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 12V output voltage. The input of voltage conversion chip U3 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 5V output voltage. The input of voltage conversion chip U4 is connected to the output of voltage conversion chip U1, converting the 5.5V intermediate voltage into a 3.3V output voltage. The 12V, 5V, and 3.3V output voltages are used to drive independent functional modules with different voltage requirements in the circuit system.

3. The driving circuit according to claim 1, characterized in that, The main controller unit uses a control chip U5; the network communication and sensing feedback unit is connected to the control chip U5 via a 16-bit data bus, and the power drive unit is connected to the control chip U5 via an I / O port.

4. The driving circuit according to claim 3, characterized in that, The main controller unit also includes: Configuration interface J1 is coupled to the programming pin of control chip U5 and is used to program the control program to control chip U5. Crystal oscillator Y1 is coupled to the oscillator input terminal of control chip U5, providing a reference clock frequency for control chip U5; The buzzer LS1 is controlled by the I / O pins of the control chip U5 and is used to generate acoustic warning or operation prompt signals. LED indicators D5 and D6 are respectively coupled to the I / O pins of the control chip U5 and are used to indicate the system status through optical signals.

5. The driving circuit according to claim 1, characterized in that, The network communication and sensing feedback unit includes: The magnetic encoder chip U9 is coupled to the motor output terminal of the power drive unit and is used to generate digital signals of motor speed and position based on the position detection of the servo motor rotor magnetic field. The RS232 serial communication chip U12 establishes a data communication link with the control chip of the main controller unit through the UART protocol; The CAN communication chip U13 establishes a data communication link with the control chip of the main controller unit through the CAN bus protocol; Optical couplers U10 and U11 have their input terminals coupled to the digital I / O pins of the control chip of the main controller unit, and their output terminals coupled to external signal nodes. Electrical isolation and noise suppression between the input and output terminals are achieved through an optical coupling mechanism.

6. The driving circuit according to claim 1, characterized in that, The power drive unit includes: Gate driver chips U6 and U7 have their input terminals coupled to the control signal output terminal of the main controller unit via an isolated communication interface, and are used to convert low-voltage control signals into high-voltage drive signals. MOSFETs Q3, Q4, Q5, and Q6 have their gates coupled to the output terminals of gate driver chips U6 and U7, respectively, and their drains and sources form an H-bridge power topology. The gate driver chips U6 and U7 suppress the interference of high-power circuit noise on the control signal through an electrical isolation mechanism; the H-bridge power topology adjusts the direction and amplitude of the output current by controlling the conduction sequence of MOSFETs Q3, Q4, Q5 and Q6, so as to realize the forward and reverse rotation and speed control of the DC brushed motor.

7. The driving circuit according to claim 1, characterized in that, The power drive unit also includes a current sensing amplifier U8, whose input is coupled to the current output path of the H-bridge power topology, converting the analog current signal into a digital signal, and whose output is communicatively connected to the main controller unit. The main controller unit adjusts the PWM output duty cycle in real time based on the digital signal.

8. The driving circuit according to claim 1, characterized in that, The functional interface unit includes: Motor interface J2 is coupled to the power drive unit for connecting an external DC brushed motor; The power input interface J3 is coupled to the high-voltage input terminal of the power supply and conversion unit and is used to connect to a DC input power supply. The emergency power-off isolation interface J4 is connected to the main controller unit via an optocoupler isolation circuit and is used to receive external safety shutdown signals. RS232 bus interface J5 is used for communication connection with the RS232 serial communication chip of the network communication and sensing feedback unit. The dual-channel CAN bus interface J6 is used for communication connection with the CAN communication chip of the network communication and sensing feedback unit.

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