Spinning handlebar twist angle detection system based on potentiometer resistance identification and interaction method thereof

Abstract

The application belongs to the technical field of motion equipment human-computer interaction, in particular to a spin bike handlebar twist angle detection system based on potentiometer resistance value recognition and an interaction method thereof, which comprises a hardware device and a circuit module, characterized in that the hardware device comprises a mounting sleeve, a single-turn carbon film potentiometer is fixed on the upper side of the mounting sleeve, a spring automatic rebound assembly is fixed on the upper side of the mounting sleeve and outside the single-turn carbon film potentiometer, a physical limiter is fixed on the inner wall of the spring automatic rebound assembly, and a conversion mounting connecting piece is fixed on the upper side of the single-turn carbon film potentiometer and inside the spring automatic rebound assembly; the circuit module comprises a dynamic resistance value-angle conversion module, the angle resolution of the handlebar rotation in the application is 0.8°, the rotation precision is greatly improved, the device is provided with an automatic rebound mechanism, the rebound error is less than 0.5°, the operation reality is increased, the limiting impact force is less than 35N, and the potentiometer service life is more than 200,000 times.

Description

Technical Field

[0001] This invention relates to the field of human-computer interaction technology for sports equipment, specifically to a system for detecting the handlebar twist angle of a stationary bicycle based on potentiometer resistance value recognition and its interaction method. Background Technology

[0002] Nowadays, people are paying more and more attention to their physical condition and exercising actively. Cycling, as a healthy and natural aerobic exercise, has many advantages in preventing high blood pressure, preventing brain aging, improving cardiopulmonary function, improving memory, and making the body healthier and more balanced. However, outdoor cycling is easily affected by time, weather, and location, and has a relatively high risk factor. Therefore, more and more people are now choosing to exercise by using indoor bikes in gyms.

[0003] In order to detect the torsion angle of the handlebars in real time during the use of exercise bikes, a handlebar torsion angle detection system is proposed. However, the current detection system still has the following technical problems in use:

[0004] Current photoelectric encoders are susceptible to dust and humidity, and Hall sensors have poor linearity in low-cost solutions, resulting in insufficient accuracy. Current detection systems lack automatic rebound mechanisms, affecting the realism of operation and providing no physical feedback. Mechanical limit structures are prone to overload damage to potentiometers, resulting in limit defects.

[0005] Therefore, a spin bike handlebar twist angle detection system and its interaction method are proposed to solve the problems mentioned above. Summary of the Invention

[0006] The purpose of this invention is to provide a system for detecting the handlebar twist angle of a stationary bicycle based on potentiometer resistance identification and its interaction method, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a dynamic bicycle handlebar twist angle detection system based on potentiometer resistance value recognition, comprising hardware equipment and a circuit module. The hardware equipment includes a mounting sleeve, on the upper side of which a single-turn carbon film potentiometer is fixed. On the upper side of the mounting sleeve and outside the single-turn carbon film potentiometer, a spring automatic return assembly is fixed. A physical limiter is fixed to the inner wall of the spring automatic return assembly. A conversion mounting connector is fixed on the upper side of the single-turn carbon film potentiometer and inside the spring automatic return assembly. The circuit module includes a dynamic resistance-angle conversion module.

[0008] Preferably, the dynamic resistance-angle conversion module uses a three-point calibration method to compensate for nonlinear errors.

[0009] Preferably, the preload of the automatic spring return assembly is adjustable, and this is achieved through an end adjusting bolt.

[0010] Preferably, the physical limiter includes a contact micro switch that sends an emergency stop signal to the MCU when triggered.

[0011] An interactive method for detecting the handlebar twist angle of a stationary bike based on potentiometer resistance recognition is described below.

[0012] Step 1: Real-time acquisition of the resistance value of the single-turn carbon film potentiometer (2) and conversion into an angle value: The dynamic resistance-angle conversion module acquires the analog voltage signal output from the sliding end of the single-turn carbon film potentiometer in real time through the ADC interface, establishes a calibration curve between resistance and angle, records the resistance data of the single-turn carbon film potentiometer at different rotation angles through multiple experiments, and constructs an accurate correspondence using a linear interpolation algorithm; using a sliding window filtering algorithm, the dynamic resistance-angle conversion module stores multiple angle values ​​acquired continuously, calculates the average value of these values ​​as the final effective angle output;

[0013] Step 2: When the angle value is >40°, a tank turret turning command is generated: The dynamic resistance-angle conversion module compares the real-time converted angle value with the preset threshold of 40°. When the angle value is ≥40°, the command generation process is triggered. The direction of handlebar rotation is determined by the direction of resistance change. The command carries the direction parameter and uses the UDP protocol to encapsulate the data. The dynamic resistance-angle conversion module sends the command through the Bluetooth module. After receiving and parsing the data packet, the VR device drives the tank turret model to rotate according to the angle and direction.

[0014] Step 3: After releasing the handlebars, the spring reset signal is synchronized to the VR scene: When the user releases the handlebars, the spring automatic rebound component drives the handlebars to reset. The built-in micro switch of the spring automatic rebound component (3) triggers a low-level signal to the dynamic resistance-angle conversion module. At this time, the angle value drops back to 0°±5%. After receiving the reset signal, the dynamic resistance-angle conversion module sends a stop steering command. The physical limiter works, and the tank turret in the VR scene stops rotating and returns to center, ensuring that the physical action is synchronized with the virtual scene in real time.

[0015] Preferably, in step two, the relationship between the direction of resistance change and the direction of handlebar rotation is as follows: an increase in resistance corresponds to a left turn, and a decrease corresponds to a right turn; the direction parameters are 0x01 = left turn and 0x02 = right turn.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] In this application, the angular resolution of the handlebar rotation is 0.8°, which greatly improves the rotation accuracy. The device is equipped with an automatic rebound mechanism with a rebound error of <0.5°, which increases the realism of operation. The limit impact force is <35N and the potentiometer life is >200,000 times. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention from a bottom view;

[0019] Figure 2 This is a top-view structural diagram of our side;

[0020] Figure 3 This is a schematic diagram of the exploded structure of the present invention.

[0021] In the diagram: 1. Mounting sleeve; 2. Single-turn carbon film potentiometer; 3. Spring automatic return assembly; 4. Physical limiter; 5. Adapter mounting connector. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. 37

[0024] Example:

[0025] Please see Figure 1-3 The present invention provides a technical solution:

[0026] The exercise bike handlebar torsion angle detection system based on potentiometer resistance recognition includes hardware devices and circuit modules. The hardware devices include a mounting sleeve 1, a single-turn carbon film potentiometer 2 fixed on the upper side of the mounting sleeve 1, an automatic spring return assembly 3 fixed on the upper side of the mounting sleeve 1 and outside the single-turn carbon film potentiometer 2, a physical limiter 4 fixed on the inner wall of the automatic spring return assembly 3, and a conversion mounting connector 5 fixed on the upper side of the single-turn carbon film potentiometer 2 and inside the automatic spring return assembly 3. The circuit module includes a dynamic resistance-angle conversion module.

[0027] The dynamic resistance-angle conversion module uses a three-point calibration method to compensate for nonlinear errors.

[0028] The preload of the automatic spring return assembly 3 is adjustable, and this is achieved through the end adjusting bolt.

[0029] The physical limiter 4 includes a contact micro switch that sends an emergency stop signal to the MCU when triggered.

[0030] An interactive method for detecting the handlebar twist angle of a stationary bike based on potentiometer resistance recognition is described below.

[0031] Step 1: Real-time acquisition of the resistance value of the single-turn carbon film potentiometer 2 and conversion to an angle value: The dynamic resistance-angle conversion module acquires the analog voltage signal output from the sliding end of the single-turn carbon film potentiometer 2 in real time through the ADC interface, establishes a calibration curve between resistance and angle, records the resistance data of the single-turn carbon film potentiometer 2 at different rotation angles through multiple experiments, and constructs an accurate correspondence using a linear interpolation algorithm; using a sliding window filtering algorithm, the dynamic resistance-angle conversion module stores multiple continuously acquired angle values ​​and calculates the average value of these values ​​as the final effective angle output;

[0032] Step 2: When the angle value is >40°, a tank turret turning command is generated: The dynamic resistance-angle conversion module compares the real-time converted angle value with the preset threshold of 40°. When the angle value is ≥40°, the command generation process is triggered. The direction of handlebar rotation is determined by the direction of resistance change. The command carries the direction parameter and uses the UDP protocol to encapsulate the data. The dynamic resistance-angle conversion module sends the command through the Bluetooth module. After receiving and parsing the data packet, the VR device drives the tank turret model to rotate according to the angle and direction.

[0033] Step 3: After releasing the handlebars, the spring reset signal is synchronized to the VR scene: When the user releases the handlebars, the automatic spring return component 3 drives the handlebars to reset. The micro switch built into the automatic spring return component 3 triggers a low-level signal to the dynamic resistance-angle conversion module. At this time, the angle value drops back to 0°±5%. After receiving the reset signal, the dynamic resistance-angle conversion module sends a stop steering command. The physical limiter 4 works, and the tank turret in the VR scene stops rotating and returns to center, ensuring that the physical action is synchronized with the virtual scene in real time.

[0034] In step two, the relationship between the direction of resistance change and the direction of handlebar rotation is as follows: an increase in resistance indicates a left turn, and a decrease indicates a right turn; the direction parameters are 0x01 = left turn and 0x02 = right turn.

[0035] The single-turn carbon film potentiometer 2 needs to be coaxially mounted. A single-turn carbon film potentiometer 2 with good linear characteristics (e.g., nominal resistance 10kΩ, accuracy ±5%) should be selected, and its shaft should be coaxially connected to the rotating shaft of the exercise bike handlebars via a flexible coupling. This connection method ensures that the sliding contact of the potentiometer rotates synchronously when the handlebars rotate, and the flexible coupling can compensate for minor installation deviations, reducing the impact of mechanical stress on the potentiometer. The two fixed terminals of the single-turn carbon film potentiometer 2 are connected to the positive terminal of the DC power supply (e.g., 3.3V) and ground, respectively, while the sliding terminal serves as the signal output terminal, connected to the subsequent data acquisition circuit.

[0036] When the handlebars are twisted, the spring inside the automatic spring return assembly 3 deforms and stores elastic potential energy; once the user releases the handlebars, the spring quickly rebounds, causing the handlebars to return to their initial position. At the same time, the spring return assembly 3 has a built-in contact microswitch. When the handlebars are reset, the microswitch is triggered by a change in the magnetic field, generating an electrical signal that is transmitted to the microcontroller as a spring reset signal.

[0037] The physical limiter 4 is also equipped with a strain gauge or pressure sensor. When the force applied to the limiter by the handlebar exceeds the set threshold (such as 50N), the sensor outputs a signal to the dynamic resistance-angle conversion module, triggering the overload protection mechanism, temporarily cutting off the power supply to the potentiometer or issuing an alarm to prevent equipment damage.

[0038] Resistance-angle dynamic mapping system:

[0039] Hardware configuration: A single-turn carbon film potentiometer B103 is coaxially mounted on the handlebar swivel shaft;

[0040] Algorithm Innovation:

[0041] Python

[0042] copy

[0043] download

[0044] # Sample code (actual code needs to be embedded in the microcontroller firmware)

[0045] def resistance_to_angle(R):

[0046] # Establish a piecewise linear compensation model for resistance and angle

[0047] if R < R_min: return 0 # Zero-position calibration

[0048] elif R > R_max: return max_angle # Full-scale protection

[0049] else:

[0050] # Compensation for nonlinear errors using the three-point calibration method

[0051] k1 = (θ_mid - θ_min) / (R_mid - R_min)

[0052] k2 = (θ_max - θ_mid) / (R_max - R_mid)

[0053] return k1*(R-R_min) if R < R_mid else θ_mid + k2*(R-R_mid)

[0054] Spring self-rebound composite structure:

[0055] Coaxial dual modules:

[0056] Inner layer: 304 stainless steel torsion spring (elastic coefficient k=1.8N·m / rad)

[0057] Outer layer: Potentiometer rotating shaft sleeve;

[0058] Dynamic coupling: The two ends of the spring are fixed to the frame base and the axle ratchet respectively, so as to achieve automatic centering after ±60° rotation;

[0059] The combination of polycarbonate limiting blocks and metal damping pads inside the physical limiter 4 reduces impact noise.

[0060] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A motion bicycle handlebar twist angle detection system based on potentiometer resistance value recognition, comprising hardware devices and circuit modules, characterized in that, The hardware device includes a mounting sleeve (1), on the upper side of which a single-turn carbon film potentiometer (2) is fixed. On the upper side of the mounting sleeve (1) and outside the single-turn carbon film potentiometer (2), a spring automatic return assembly (3) is fixed. On the inner wall of the spring automatic return assembly (3), a physical limiter (4) is fixed. On the upper side of the single-turn carbon film potentiometer (2) and inside the spring automatic return assembly (3), a conversion mounting connector (5) is fixed. The circuit module includes a dynamic resistance-angle conversion module. The rotating shaft of the single-turn carbon film potentiometer (2) is coaxially connected to the rotating shaft of the exercise bike handlebar. The dynamic resistance-angle conversion module uses a three-point calibration method to compensate for nonlinear errors. The physical limiter (4) includes a contact micro switch, which sends an emergency stop signal to the MCU when triggered; The physical limiter (4) is also equipped with a strain gauge or pressure sensor. When the force applied by the handlebar to the physical limiter (4) exceeds the set threshold, the strain gauge or pressure sensor outputs a signal to the dynamic resistance-angle conversion module, triggering the overload protection mechanism, temporarily cutting off the power supply to the single-turn carbon film potentiometer (2) or issuing an alarm to prevent damage.

2. The dynamic bicycle handlebar twist angle detection system based on potentiometer resistance recognition according to claim 1, characterized in that: The preload of the automatic spring return assembly (3) is adjustable and is achieved through the end adjustment bolt.

3. The interactive method of the motion bicycle handlebar twist angle detection system based on potentiometer resistance recognition according to any one of claims 1-2, characterized in that: The specific steps of this interaction method are as follows: Step 1: Real-time acquisition of the resistance value of the single-turn carbon film potentiometer (2) and conversion into an angle value: The dynamic resistance-angle conversion module acquires the analog voltage signal output from the sliding end of the single-turn carbon film potentiometer (2) in real time through the ADC interface, establishes a calibration curve between resistance and angle, records the resistance data of the single-turn carbon film potentiometer (2) at different rotation angles through multiple experiments, and constructs an accurate correspondence using a linear interpolation algorithm; the dynamic resistance-angle conversion module stores multiple continuously acquired angle values ​​using a sliding window filtering algorithm, and calculates the average value of these values ​​as the final effective angle output; Step 2: When the angle value is >40°, a tank turret turning command is generated: The dynamic resistance-angle conversion module compares the real-time converted angle value with the preset threshold of 40°. When the angle value is >40°, the command generation process is triggered. The direction of handlebar rotation is determined by the direction of resistance change. The command carries the direction parameter and uses the UDP protocol to encapsulate the data. The dynamic resistance-angle conversion module sends the command through the Bluetooth module. After receiving and parsing the data packet, the VR device drives the tank turret model to rotate according to the angle and direction. Step 3: After releasing the handlebars, the spring reset signal is synchronized to the VR scene: When the user releases the handlebars, the spring automatic rebound component (3) drives the handlebars to reset. The built-in micro switch of the spring automatic rebound component (3) triggers a low-level signal to the dynamic resistance-angle conversion module. At this time, the angle value drops back to 0°±5%. After receiving the reset signal, the dynamic resistance-angle conversion module sends a stop steering command. The physical limiter (4) works, and the tank turret in the VR scene stops rotating and returns to center, ensuring that the physical action is synchronized with the virtual scene in real time.

4. The interactive method of the dynamic bicycle handlebar twist angle detection system based on potentiometer resistance recognition according to claim 3, characterized in that: In step two, the relationship between the direction of resistance change and the direction of handlebar rotation is as follows: an increase in resistance indicates a left turn, and a decrease indicates a right turn; the direction parameters are 0x01 = left turn and 0x02 = right turn.

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