Intelligent robot rotary encoder human-machine interaction module

Abstract

This utility model discloses an intelligent robot rotary encoder human-machine interaction module, including: a rotary encoder, a push-button switch signal conditioning circuit, an encoder A-phase signal conditioning circuit, an encoder B-phase signal conditioning circuit, and a power supply decoupling circuit; the rotary encoder is an incremental rotary encoder with a built-in push-button switch, having an A-phase pin, a B-phase pin, a common terminal pin, and a push-button switch pin; the encoder A-phase signal conditioning circuit is electrically connected to the A-phase pin of the rotary encoder and outputs to the second GPIO port of the MCU; the encoder B-phase signal conditioning circuit is electrically connected to the B-phase pin of the rotary encoder and outputs to the third GPIO port of the MCU; this intelligent robot rotary encoder human-machine interaction module has the characteristics of high quadrature phase matching accuracy, good debouncing effect, strong anti-interference ability, low power consumption, and compact structure.

Description

Technical Field

[0001] This utility model relates to the field of human-computer interaction control for intelligent robots, specifically to a human-computer interaction module for an intelligent robot rotary encoder. Background Technology

[0002] With the rapid development of intelligent robot technology, robots are increasingly being used in industrial manufacturing, service sectors, and home environments. During operation, operators need to adjust parameters (such as speed, torque, and position), switch modes, and confirm commands through a physical interface. The human-machine interface, acting as a bridge between the operator and the robot, directly impacts operational efficiency and user experience. Rotary encoders, due to their intuitive operation and precise position feedback, have become a crucial input element in intelligent robot human-machine interfaces.

[0003] However, existing technologies have the following shortcomings when applying rotary encoders to human-computer interaction in intelligent robots.

[0004] First, it occupies too much space and resources. Traditional solutions use separate buttons to implement the add, subtract, and confirm functions, requiring multiple buttons to correspond to different operations, which occupies too much PCB area and MCU pin resources, which is not conducive to the miniaturization design of robots.

[0005] Second, insufficient debouncing. Insufficient debouncing at the encoder interface can cause bouncing of the mechanical contacts during movement, leading to false counting, affecting the accuracy of rotation direction judgment, and causing abnormal phenomena such as jumps or reversals during parameter adjustment.

[0006] Third, channel delay mismatch. The inconsistent RC delays of the encoder's A and B phase signal channels cause directional misjudgments during quadrature decoding, especially at high speeds, where the error rate increases significantly, severely impacting the user experience.

[0007] Fourth, insufficient anti-interference capability. The lack of ESD protection and EMI filtering for encoder signals makes them prone to abnormalities in environments with strong electromagnetic interference inside the robot (such as high-frequency interference generated by the motor driver), leading to false triggering or missed detection. Utility Model Content

[0008] The purpose of this invention is to provide a human-machine interaction module for an intelligent robot rotary encoder. This intelligent robot rotary encoder human-machine interaction module features high orthogonal phase matching accuracy, good de-jitter effect, strong anti-interference capability, low power consumption, and compact structure.

[0009] The above-mentioned technical objective of this utility model is achieved through the following technical solution: A human-machine interaction module for an intelligent robot rotary encoder includes a rotary encoder (SW1), a push-button switch signal conditioning circuit, an encoder A-phase signal conditioning circuit, an encoder B-phase signal conditioning circuit, and a power decoupling circuit. The rotary encoder (SW1) is an incremental rotary encoder with a built-in push-button switch, having an A-phase pin, a B-phase pin, a common terminal pin, and a push-button switch pin. The push-button switch signal conditioning circuit is electrically connected to the push-button switch pin of the rotary encoder (SW1) and outputs to the first GPIO port of the MCU. The encoder A-phase signal conditioning circuit is electrically connected to the A-phase pin of the rotary encoder (SW1) and outputs to the second GPIO port of the MCU. The encoder B-phase signal conditioning circuit is electrically connected to the B-phase pin of the rotary encoder (SW1) and outputs to the third GPIO port of the MCU. The common terminal pin of the rotary encoder (SW1) is grounded. The power decoupling circuit is connected between the power rail and ground.

[0010] This invention is further configured such that the push-button switch signal conditioning circuit includes a first pull-up resistor (R28) and a first debounce capacitor (C28). One end of the first pull-up resistor (R28) is connected to the power rail, and the other end is connected to a signal node. The signal node is electrically connected to the push-button switch pin of the rotary encoder (SW1). The first debounce capacitor (C28) is connected between the signal node and ground. The signal node is connected to the first GPIO port of the MCU.

[0011] This invention is further configured such that the encoder A-phase signal conditioning circuit adopts a dual-resistor, single-capacitor topology, including a second pull-up resistor (R29), a first series protection resistor (R30), and a second debouncing capacitor (C20). One end of the second pull-up resistor (R29) is connected to the power rail, and the other end is connected to the A-phase signal node. The A-phase signal node is electrically connected to the A-phase pin of the rotary encoder (SW1). The first series protection resistor (R30) is connected in series between the A-phase signal node and the second GPIO port of the MCU. The second debouncing capacitor (C20) is connected between the second GPIO port of the MCU and ground.

[0012] This invention is further configured such that the encoder B-phase signal conditioning circuit is symmetrically arranged with the encoder A-phase signal conditioning circuit, including a third pull-up resistor (R31), a second series protection resistor (R32), and a third debouncing capacitor (C21). One end of the third pull-up resistor (R31) is connected to the power rail, and the other end is connected to the B-phase signal node. The B-phase signal node is electrically connected to the B-phase pin of the rotary encoder (SW1). The second series protection resistor (R32) is connected in series between the B-phase signal node and the third GPIO port of the MCU. The third debouncing capacitor (C21) is connected between the third GPIO port of the MCU and ground.

[0013] The present invention is further configured such that: the power supply decoupling circuit includes a decoupling capacitor (C22), which is connected between the power rail and ground, and provides local high-frequency decoupling for the push-button switch signal conditioning circuit, the encoder A-phase signal conditioning circuit and the encoder B-phase signal conditioning circuit.

[0014] This invention is further configured such that: the first pull-up resistor (R28), the second pull-up resistor (R29), the first series protection resistor (R30), the third pull-up resistor (R31), and the second series protection resistor (R32) are all precision resistors with the same resistance value. The first debounce capacitor (C28), the second debounce capacitor (C20), and the third debounce capacitor (C21) are all capacitors with the same capacitance value.

[0015] This invention is further configured such that: the resistance values ​​of the first pull-up resistor (R28), the second pull-up resistor (R29), the first series protection resistor (R30), the third pull-up resistor (R31), and the second series protection resistor (R32) are all 4.99kΩ, with a tolerance of 1%. The capacitance values ​​of the first debouncing capacitor (C28), the second debouncing capacitor (C20), and the third debouncing capacitor (C21) are all 10nF. The capacitance value of the decoupling capacitor (C22) is 100nF. The voltage of the power rail is 3.3V.

[0016] The present invention is further configured such that: the rotary encoder (SW1) is an ALPS EC11L series low-profile incremental rotary encoder, model EC11L1525G01, and the metal housing of the rotary encoder (SW1) is grounded.

[0017] In summary, this utility model has the following beneficial effects: 1. High-precision quadrature decoding achieved through a fully matched dual-resistor topology: This invention employs a dual-resistor topology of "pull-up resistor + series resistor" in each encoder channel, with all five resistors using the same resistance value of 4.99kΩ (1% tolerance). This design ensures that the signal propagation delay of the A-phase channel is strictly equal to that of the B-phase channel. Even with systematic deviations in mass production, the two channels maintain synchronous offset, with the relative delay difference approaching zero. The RC time constant matching accuracy is better than approximately 5.1%, corresponding to a time constant deviation of no more than 2.5μs, a quadrature phase error of approximately 0.09°, and a direction misjudgment probability approaching zero.

[0018] 2. Enhanced Debouncing Effect with a Two-Stage RC Filter Architecture: Each encoder channel forms a two-stage filter network. The first stage consists of a pull-up resistor and the distributed capacitance of the encoder contacts for pre-filtering. The second stage consists of a series resistor and a debouncing capacitor for precise RC low-pass filtering, with a cutoff frequency of approximately 3.19kHz. The total order of the two-stage filtering is second-order, exhibiting a steeper roll-off characteristic compared to a single-stage RC filter, significantly enhancing the suppression of mechanical contact bounce noise.

[0019] 3. Multiple protection functions achieved through series resistors: The first series protection resistor (R30) and the second series protection resistor (R32) simultaneously provide ESD protection with current limiting, short-circuit protection, and EMI filtering. In the event of electrostatic discharge, transient current is limited to a safe range, and energy is dissipated across the resistor in conjunction with the MCU's internal ESD protection diode. Simultaneously, together with the debounce capacitor, they form a low-pass filter to filter out high-frequency electromagnetic interference generated by the robot motor driver. A single resistor replaces the multiple components required in traditional designs, reducing the number of components and saving approximately 40% of PCB area.

[0020] 4. Power-optimized bias strategy: A 4.99kΩ resistor value achieves a triple balance of zero static power consumption, low dynamic power consumption, and strong noise immunity. When the encoder is not rotating or the button is not pressed, the contacts are open, the pull-up resistor has no loop current, and the static power consumption is close to zero. During rotation, the dynamic power consumption per channel does not exceed 2.18mW. Compared with a 1kΩ pull-up resistor, the dynamic power consumption is reduced by approximately 80%, and compared with a 10kΩ pull-up resistor, the noise immunity is improved by approximately 6dB.

[0021] 5. Design for Manufacturability with a Unified BOM: All five resistors in this circuit are 4.99kΩ with the same resistance value and package. The capacitors are available in only two sizes (10nF and 100nF), requiring only one resistor slot on the pick-and-place machine. This design reduces placement programming time, lowers incoming material inspection batches and quality control costs, achieves zero misplacement rate, and unifies optimal circuit performance with optimal manufacturing yield.

[0022] 6. Selection of low-profile encoders to fit compact spaces: ALPS EC11L series low-profile rotary encoders are selected, with a total height of about 12.5mm, which is much lower than the standard model of about 20mm. This makes them suitable for the limited space of the operation panel inside the intelligent robot, and allows a single knob to achieve complex operations that would require multiple buttons in traditional solutions. Attached Figure Description

[0023] Figure 1 This is the overall circuit schematic diagram of this utility model. Detailed Implementation

[0024] In the description of this utility model, it should be noted that the connection relationship indicated by terms such as "connection" and "electrical connection" is an electrical connection relationship, which can be a direct electrical connection or an indirect electrical connection through intermediate components. The circuit connection methods indicated by terms such as "pull-up," "series," and "parallel" are conventional circuit connection methods well known to those skilled in the art.

[0025] like Figure 1 As shown, this utility model provides a human-machine interface module for an intelligent robot rotary encoder, used to realize a multi-functional composite input interface for intelligent robots, including parameter adjustment, menu navigation, and confirmation operations. The module uses the ALPSEC11L1525G01 low-profile rotary encoder as the core input element, and sends three signals to the three GPIO ports of the MCU through a precision resistor network and an RC filter network.

[0026] The module consists of the following parts: rotary encoder (SW1), push-button switch signal conditioning circuit, encoder A-phase signal conditioning circuit, encoder B-phase signal conditioning circuit, and power supply decoupling circuit.

[0027] The rotary encoder (SW1) is an EC11L1525G01 low-profile incremental rotary encoder manufactured by ALPS. This encoder integrates a push-button switch function and has a total height of approximately 12.5mm. The rotary encoder (SW1) has three rotary encoding pins: the A-phase pin (phase A output), the C pin (common terminal), and the B-phase pin (phase B output). The push-button switch, located on the top of the encoder, has two pins and is activated when pressed. The metal casing of the rotary encoder (SW1) is grounded, providing electromagnetic shielding. The working principle of the rotary encoder (SW1) is as follows: During rotation, two sets of internal contacts alternately connect to the common terminal C with a 90° phase difference, generating quadrature pulse signals. The MCU determines the rotation direction by detecting the lead / lag relationship between phases A and B, and determines the rotation speed by the pulse frequency. During clockwise rotation, phase A generates a falling edge first, followed by phase B; during counterclockwise rotation, phase B generates a falling edge first, followed by phase A.

[0028] The push-button switch signal conditioning circuit is used to implement functions such as menu confirmation, parameter saving, and mode switching. It includes a first pull-up resistor (R28) and a first debounce capacitor (C28). The first pull-up resistor (R28) is a precision surface-mount resistor with a resistance of 4.99kΩ and a tolerance of 1%. One end of the first pull-up resistor (R28) is connected to the 3.3V power rail (3V3X), and the other end is connected to the signal node (Node_SW). The signal node (Node_SW) is electrically connected to the push-button switch pin of the rotary encoder (SW1). The first debounce capacitor (C28) is a surface-mount capacitor with a capacitance of 10nF, connected between the signal node (Node_SW) and ground. The first pull-up resistor (R28) and the first debounce capacitor (C28) form a first-order RC low-pass filter to filter out mechanical contact bounce noise. The RC time constant is 49.9μs, the cutoff frequency is approximately 3.19kHz, and the rise time is approximately 110μs. The signal node (Node_SW) is connected to the first GPIO port (PA7X) of the MCU. The reason for choosing 4.99kΩ instead of the conventional 10kΩ is that, in the strong electromagnetic interference environment inside the robot, the lower pull-up impedance provides stronger noise immunity.

[0029] The encoder A-phase signal conditioning circuit adopts a dual-resistor, single-capacitor topology of "pull-up resistor + series resistor + debounce capacitor," including a second pull-up resistor (R29), a first series protection resistor (R30), and a second debounce capacitor (C20). The second pull-up resistor (R29) is a precision surface-mount resistor with a resistance of 4.99kΩ and a tolerance of 1%. One end of the second pull-up resistor (R29) is connected to the 3.3V power rail (3V3X), and the other end is connected to the A-phase signal node (Node_A). The common terminal pin (Pin C) of the rotary encoder (SW1) is directly connected to ground. The A-phase signal node (Node_A) is electrically connected to the A-phase pin of the rotary encoder (SW1). When the encoder rotates, closing the internal contacts between the A-phase pin and the common terminal pin, the A-phase signal node (Node_A) is shorted to ground. When the encoder contacts are open, the potential of the A-phase signal node (Node_A) is 3.3V (logic HIGH); when the encoder contacts are closed, the potential of the A-phase signal node (Node_A) is approximately 0V (logic LOW). When the contacts are closed, the current flowing through the second pull-up resistor (R29) is approximately 0.66mA. The first series protection resistor (R30) is a precision surface-mount resistor with a resistance of 4.99kΩ and a tolerance of 1%, connected in series between the A-phase signal node (Node_A) and the second GPIO port (PB2X) of the MCU. The first series protection resistor (R30) simultaneously provides ESD protection current limiting, RC filtering of the R component, and impedance isolation. In the event of electrostatic discharge, the first series protection resistor (R30) can limit the transient current to approximately 1.6A (based on an 8kV electrostatic discharge voltage), which, together with the MCU's internal ESD protection diode, dissipates energy across the resistor. Even if the encoder pin is short-circuited to the power supply, the current is limited to approximately 0.66mA. The second debounce capacitor (C20) is a surface-mount capacitor with a capacitance of 10nF, connected between the second GPIO port (PB2X) of the MCU and ground. The first series protection resistor (R30) and the second debounce capacitor (C20) constitute the second-stage RC low-pass filter, with an RC time constant of 49.9μs and a cutoff frequency of approximately 3.19kHz.

[0030] The encoder B-phase signal conditioning circuit is symmetrically configured with the encoder A-phase signal conditioning circuit, including a third pull-up resistor (R31), a second series protection resistor (R32), and a third debounce capacitor (C21). The third pull-up resistor (R31) is a precision surface-mount resistor with a resistance of 4.99kΩ and a tolerance of 1%. One end of the third pull-up resistor (R31) is connected to the 3.3V power rail (3V3X), and the other end is connected to the B-phase signal node (Node_B). The B-phase signal node (Node_B) is electrically connected to the B-phase pin of the rotary encoder (SW1). The second series protection resistor (R32) is a precision surface-mount resistor with a resistance of 4.99kΩ and a tolerance of 1%, connected in series between the B-phase signal node (Node_B) and the MCU's third GPIO port (PB0X). The third debounce capacitor (C21) is a surface-mount capacitor with a capacitance of 10nF, connected between the MCU's third GPIO port (PB0X) and ground. The RC time constant formed by the second series protection resistor (R32) and the third debounce capacitor (C21) is also 49.9μs, and the cutoff frequency is about 3.19kHz, ensuring strict matching with the time constant of the A phase channel.

[0031] The power supply decoupling circuit includes a decoupling capacitor (C22). The decoupling capacitor (C22) is a surface-mount capacitor with a capacitance of 100nF, connected between the 3.3V power rail (3V3X) and ground. The decoupling capacitor (C22) provides local high-frequency decoupling for the entire encoder module, suppressing power rail ripple caused by button presses and encoder rotation, and covering mid-to-high frequency noise.

[0032] This invention employs a dual-resistor topology with full-channel precision matching. The first pull-up resistor (R28), the second pull-up resistor (R29), the first series protection resistor (R30), the third pull-up resistor (R31), and the second series protection resistor (R32) are all precision resistors with the same resistance value of 4.99kΩ and a tolerance of 1%. The first debounce capacitor (C28), the second debounce capacitor (C20), and the third debounce capacitor (C21) are all capacitors with the same capacitance value of 10nF. This design ensures strict matching of the RC time constants of the A / B phase channels, thereby achieving high-precision quadrature decoding.

[0033] The working principle of this utility model is as follows: During the push-button switch detection phase: When the button is not pressed, the signal node (Node_SW) is pulled up to 3.3V through the first pull-up resistor (R28), and the MCU's first GPIO port (PA7X) detects a high level. When the operator presses the push-button switch on top of the rotary encoder (SW1), the signal node (Node_SW) is connected to ground through the encoder's internal button contact, and the potential jumps from 3.3V to 0V. The MCU detects the falling edge at the first GPIO port (PA7X), triggering a button interrupt or query to realize functions such as menu confirmation, parameter saving, and mode switching. The first debounce capacitor (C28) and the first pull-up resistor (R28) form an RC low-pass filter to filter out the high-frequency noise generated by the mechanical contact bounce during button operation.

[0034] Rotation direction detection stage: When the operator rotates the encoder, the two sets of contacts inside the rotary encoder (SW1) alternately connect to the common terminal with a 90° phase difference, generating quadrature pulse signals on the A-phase and B-phase pins. During clockwise rotation, phase A generates a falling edge first, followed by phase B; during counter-clockwise rotation, phase B generates a falling edge first, followed by phase A. The MCU determines the direction by detecting the phase relationship of the quadrature signals at the second GPIO port (PB2X) and the third GPIO port (PB0X). Because the encoder A-phase signal conditioning circuit and encoder B-phase signal conditioning circuit adopt a completely symmetrical design, and all resistor and capacitor parameters are strictly matched, the signal propagation delays of the A-phase channel and the B-phase channel are strictly equal, ensuring the accuracy of quadrature decoding.

[0035] Rotational speed detection stage: The MCU calculates the rotational speed by measuring the time interval of the A-phase or B-phase pulses. The EC11 encoder typically outputs 15 or 20 pulses per revolution, which, combined with the time interval, can be accurately converted into rotational speed or angular velocity. Shorter pulse intervals during rapid rotation are suitable for coarse parameter adjustment; longer pulse intervals during slow rotation are suitable for fine parameter adjustment.

[0036] Typical applications in intelligent robots include: rotary encoders for parameter adjustment (speed, torque, position increase / decrease), push switches for parameter confirmation or menu access, rapid rotation for coarse parameter adjustment (large steps), slow rotation for fine parameter adjustment (small steps), and rotating while pressing can trigger compound commands (such as emergency mode switching).

[0037] This invention relates to an intelligent robot rotary encoder human-machine interaction module. Through a fully matched dual-resistor topology and a symmetrical RC filter network, it achieves high-precision quadrature decoding with a delay difference of no more than 2.5μs between the A / B phase channels and a quadrature phase error of no more than 0.09°. The de-jitter cutoff frequency for all channels is uniformly set to 3.19kHz, and the RC time constant is uniformly set to 49.9μs. Static power consumption is close to 0mA, and dynamic power consumption does not exceed 2.18mW per channel. Series resistors limit the electrostatic discharge transient current to within 1.6A. Only one type of resistor (4.99kΩ) and two types of capacitors (10nF and 100nF) are required, simplifying the bill of materials. The low-profile encoder, approximately 12.5mm in height, fits snugly in the compact panel space of robots. This invention features high quadrature phase matching accuracy, excellent de-jitter effect, strong anti-interference capability, low power consumption, compact structure, and good manufacturability.

Claims

1. A human-machine interaction module for an intelligent robot rotary encoder, characterized in that, include: The encoder comprises a rotary encoder (SW1), a push-button switch signal conditioning circuit, an encoder A-phase signal conditioning circuit, an encoder B-phase signal conditioning circuit, and a power decoupling circuit. The rotary encoder (SW1) is an incremental rotary encoder with a built-in push-button switch, having an A-phase pin, a B-phase pin, a common terminal pin, and a push-button switch pin. The push-button switch signal conditioning circuit is electrically connected to the push-button switch pin of the rotary encoder (SW1) and outputs to the first GPIO port of the MCU. The encoder A-phase signal conditioning circuit is electrically connected to the A-phase pin of the rotary encoder (SW1) and outputs to the second GPIO port of the MCU. The encoder B-phase signal conditioning circuit is electrically connected to the B-phase pin of the rotary encoder (SW1) and outputs to the third GPIO port of the MCU. The common terminal pin of the rotary encoder (SW1) is grounded. The power decoupling circuit is connected between the power rail and ground.

2. The intelligent robot rotary encoder human-machine interaction module according to claim 1, characterized in that, The push-button switch signal conditioning circuit includes a first pull-up resistor (R28) and a first debounce capacitor (C28). One end of the first pull-up resistor (R28) is connected to the power rail, and the other end of the first pull-up resistor (R28) is connected to the signal node; The signal node is electrically connected to the push-button switch pin of the rotary encoder (SW1); The first debounce capacitor (C28) is connected between the signal node and ground; The signal node is connected to the first GPIO port of the MCU.

3. The intelligent robot rotary encoder human-machine interaction module according to claim 2, characterized in that, The encoder A-phase signal conditioning circuit adopts a dual-resistor single-capacitor topology, including a second pull-up resistor (R29), a first series protection resistor (R30), and a second debouncing capacitor (C20). One end of the second pull-up resistor (R29) is connected to the power rail, and the other end of the second pull-up resistor (R29) is connected to the A-phase signal node; The A-phase signal node is electrically connected to the A-phase pin of the rotary encoder (SW1); The first series protection resistor (R30) is connected in series between the A-phase signal node and the second GPIO port of the MCU; The second debouncing capacitor (C20) is connected between the second GPIO port of the MCU and ground.

4. The intelligent robot rotary encoder human-machine interaction module according to claim 3, characterized in that, The encoder B-phase signal conditioning circuit is symmetrically arranged with the encoder A-phase signal conditioning circuit, and includes a third pull-up resistor (R31), a second series protection resistor (R32), and a third debouncing capacitor (C21). One end of the third pull-up resistor (R31) is connected to the power rail, and the other end of the third pull-up resistor (R31) is connected to the B-phase signal node; The B-phase signal node is electrically connected to the B-phase pin of the rotary encoder (SW1); The second series protection resistor (R32) is connected in series between the B-phase signal node and the third GPIO port of the MCU; The third debouncing capacitor (C21) is connected between the third GPIO port of the MCU and ground.

5. The intelligent robot rotary encoder human-machine interaction module according to claim 4, characterized in that, The power decoupling circuit includes a decoupling capacitor (C22), which is connected between the power rail and ground to provide local high-frequency decoupling for the push-button switch signal conditioning circuit, the encoder A-phase signal conditioning circuit, and the encoder B-phase signal conditioning circuit.

6. The intelligent robot rotary encoder human-machine interaction module according to claim 5, characterized in that, The first pull-up resistor (R28), the second pull-up resistor (R29), the first series protection resistor (R30), the third pull-up resistor (R31), and the second series protection resistor (R32) are all precision resistors with the same resistance value; The first debounce capacitor (C28), the second debounce capacitor (C20), and the third debounce capacitor (C21) are all capacitors with the same capacitance value.

7. The intelligent robot rotary encoder human-machine interaction module according to claim 6, characterized in that, The resistance values ​​of the first pull-up resistor (R28), the second pull-up resistor (R29), the first series protection resistor (R30), the third pull-up resistor (R31), and the second series protection resistor (R32) are all 4.99kΩ, with a tolerance of 1%. The capacitance values ​​of the first debounce capacitor (C28), the second debounce capacitor (C20), and the third debounce capacitor (C21) are all 10nF; The decoupling capacitor (C22) has a capacitance of 100nF; The voltage of the power rail is 3.3V.

8. The intelligent robot rotary encoder human-machine interaction module according to claim 7, characterized in that, The rotary encoder (SW1) is an ALPS EC11L series low-profile incremental rotary encoder, model EC11L1525G01, and the metal housing of the rotary encoder (SW1) is grounded.

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