Hand-slipping protection control method of electric control strength training apparatus

Abstract

The invention relates to the technical field of training equipment, in particular to a hand release protection control method of an electric control strength training instrument, which comprises the following steps: acquiring displacement speed data of a load component in real time by using a speed measuring device; calculating the acceleration of the load part based on the collected displacement speed data; combining the acceleration and the equivalent mass of the load component to calculate the force borne by the load component; the actual output force of the user is determined according to the force borne by the load component, the system resistance and the output force of the force generation device; the actual output force of the user is monitored in real time, and when the actual output force is reduced to zero, a hand release state is judged; and after the hand release state is monitored, the output force of the force generation device is adjusted to enable the return speed of the load component to be within a safe range. By means of accurate speed measurement and rapid and accurate force control, the safety of training is improved, the risk that a user is injured due to hand slipping in the training process is reduced, potential damage to instruments is reduced, and the device is suitable for various electric control strength training instruments and has wide application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of training equipment, and in particular to a hands-off protection control method for an electric-controlled strength training device. Background Art

[0002] As a common fitness equipment, the control of strength training equipment controls the motor output torque as the load force recovered by the traction tension component during use. The user generates a tension in the opposite direction of the load force by pulling the tension component on the transmission mechanism, thereby achieving strength training. Although traditional mechanical protection measures can reduce injuries to a certain extent, they are obviously insufficient in dealing with sudden hand-off situations; especially during high-intensity strength training, once hand-off occurs, the existing mechanical protection device may not be able to respond quickly enough, resulting in a large force continuously acting on the load component, increasing safety risks such as pinching or smashing.

[0003] The Chinese patent document (CN112439158A) discloses a control method for a strength fitness equipment, and the steps are as follows: 1) when it is detected that the training mode is turned on, the angle θ of the motor drive shaft is obtained in real time. If the angle θ of the motor drive shaft changes, the motor is controlled to generate a torque T(x) in the opposite direction to the change of the angle θ, T(x) is the torque at time x, and the torque at the final moment is T=F×R, R is the radius of the cable disc, and F is the force on the training action member at the final moment; 2) when the absolute value of the angular acceleration a of the motor drive shaft is greater than ε and its direction is opposite to the change of the angle θ in step 1) or the absolute value of the angular velocity w of the motor drive shaft is greater than ρ and its direction is opposite to the change of the angle θ in step 1), the motor is controlled to change the torque to T min There are two conditions for judging: first, the acceleration a is compared with an absolute value ε variable, and the acceleration a changes in the opposite direction to the angle θ; second, the absolute value of the angular velocity w of the motor drive shaft is greater than ρ and the direction of the angular velocity w is opposite to the change of the angle θ in step (1). If any of these two conditions are met, it is judged whether to adjust the torque to T min Obviously, the judgment conditions have limitations, and the ε variable needs to be continuously modified under different torque conditions to achieve a wider range of torque applicable conditions. Summary of the invention

[0004] The purpose of the present invention is to provide a hands-off protection control method for an electrically-controlled strength training device, which is applicable to various electrically-controlled strength training devices and can quickly respond to the user's hands-off state to avoid device damage and user injury risks caused by hands-off.

[0005] To achieve the above object, the technical solution adopted by the present invention is: A method for preventing a hand from slipping out of an electric-controlled strength training device comprises the following steps: S1. Using a speed measuring device to collect displacement speed data of a load component in real time, the load component is a training device used to output the force of a force generating device to a training part of a user; S2. Calculate the acceleration of the load component based on the collected displacement velocity data; S3. Calculate the force on the load component by combining the acceleration and the equivalent mass of the load component; S4. Determine the actual output force of the user according to the force applied to the load component, the system resistance, and the output force of the force generating device; S5, monitoring the actual output force of the user in real time, and determining that the user's hands are out of the hand state when the actual output force of the user drops to zero; S6. After detecting the release state, adjust the output force of the force generating device so that the return speed of the load component is within a safe range.

[0006] Preferably, the speed measuring device is installed at the output end of the force generating device, and is used to measure the output speed of the force generating device and the displacement speed of the load component.

[0007] Preferably, the force generating device includes but is not limited to a servo motor, a controllable force pneumatic cylinder or a controllable force hydraulic cylinder.

[0008] Preferably, step S4 satisfies the following formula: F0=Fm×a+dir×f Where: F0 is the actual output force of the user, m is the equivalent mass of the load component in the displacement direction, a is the acceleration of the load component in the displacement direction, f is the resistance of the system in the displacement direction, F is the output force of the force generating device, dir takes +1 when the movement direction is positive and takes -1 when it is negative.

[0009] Preferably, the control method of the output force of the force generating device in step S6 is as follows: during the return movement, the output force of the force generating device provides a safe return pulling force, the safe return pulling force is dynamically controlled and a maximum safe return pulling force is set as an upper limit, and the safe return speed of the load component is controlled by adjusting the output force of the force generating device, and the adjustment range of the safe return speed is a minimum return speed and a maximum return speed.

[0010] Preferably, the maximum safe return pulling force is the pulling force when the load component is returned and stopped, and the maximum safe return pulling force is assigned different pulling force values ​​according to different equipment.

[0011] Preferably, the maximum safe return tension Fs_max, the safe return tension Fs, the safe return speed Vs, the minimum return speed Vs_min and the maximum return speed Vs_max satisfy the following variable relationship: k=(Vs-Vs_min) / (Vs_max-Vs_min) Fs=Fs_max×(1-k).

[0012] Compared with the prior art, the present invention has the following beneficial effects: The method for judging the hands-off state of the present invention is to use whether the value calculated by formula (1) is 0 as a judgment condition. Compared with the tension sensor detection method, the advantages are: eliminating a tension sensor component, and achieving the same effect by calculating the same state through reusing the data of the speed detection device; compared with the detection of the sudden change of motor torque, it has a wider applicable torque range, is not easy to be triggered by mistake, and has a unified judgment method for different scenarios.

[0013] The present invention can quickly respond to the user's hands-off state, and timely limit the output force of the force-generating device, which significantly improves the safety of training; the present invention avoids the risk of damage to the device and injury to the user due to hands-off by accurately controlling the force-generating device, thereby achieving dual protection for the user and the device; the present invention can be integrated into various electrically controlled strength training devices, and specific embodiments include but are not limited to free weight trainers, strength machines, and comprehensive fitness equipment. In practical applications, the speed measuring device, responsible components, and control system can be appropriately adjusted and optimized according to the specific structure and usage requirements of the device, and has good versatility and broad market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a flow chart of the hands-off protection control of the present invention.

[0015] Figure 2 This is an acceleration curve diagram measured on the load component of the present invention.

[0016] Figure 3 It is a mechanical analysis diagram of the instant when the hand is released when the present invention is pulled right.

[0017] Figure 4 It is a mechanical analysis diagram of the instant when the hand is released when turning left.

[0018] Figure 5 This is a curve diagram of the actual output force of the user calculated according to formula (1) of the present invention.

[0019] Figure 6 This is a hands-off protection control curve diagram of the present invention. DETAILED DESCRIPTION

[0020] In order to make the above features and advantages of the present invention more obvious and easy to understand, embodiments are given below with reference to the accompanying drawings for detailed description as follows.

[0021] like Figure 1 As shown, this embodiment provides a method for controlling a hands-off protection of an electric-controlled strength training device, which specifically includes the following steps: S1. Use a speed measuring device to collect displacement speed data of a load component in real time. The load component is a training device used to output the force of a force generating device to a training part of a user. The speed measuring device is installed at the output end of the force generating device to measure the output speed of the force generating device and the displacement speed of the load component.

[0022] S2. Based on the collected displacement velocity data, calculate the acceleration of the load component, such as Figure 2 As shown in the figure, the first four peaks are the waveforms of force release during normal training exercise, and the fifth peak is the speed mutation waveform that occurs when the hand slips out of the hand during exercise. It can be clearly seen that the mutation waveform is steeper and has a higher peak value than the normal force release waveform.

[0023] S3. Calculate the force on the load component by combining the acceleration with the equivalent mass of the load component.

[0024] S4. Determine the actual output force of the user according to the force exerted on the load component, the system resistance and the output force of the force-generating device. The force-generating device includes but is not limited to a servo motor, a controllable force pneumatic cylinder or a controllable force hydraulic cylinder.

[0025] There are two types of release force states: State 1: The moment when the hand is released when pulling to the right. The force analysis is as follows: Figure 3 shown.

[0026] definition Figure 3 The positive direction is to the left, the movement value is positive, otherwise it is negative. The force F of the force device is positive, and the magnitude of acceleration is a. Because the movement direction is negative, the resistance is opposite to the movement direction, so f is positive. Because the inertial resistance force F1 generated by the accelerated movement is opposite to the direction of acceleration, the direction of acceleration is positive, so F1 is negative. Because the user remains stationary when training on the training equipment, the resultant force of all force elements of the training equipment is 0 when the user is training, that is, F+f-F1-F0=0. Therefore, in the current state, the value of the user's pulling force F0 is F0=F+f-F1, that is, F0=F+fm×a.

[0027] State 2: The moment the hand is released when returning to the left, the force analysis is as follows Figure 4 shown.

[0028] definition Figure 4The center direction is to the left, the movement value is positive, otherwise it is negative. The force F of the force device is positive, and the magnitude of acceleration is a. Because the direction of movement is positive and the resistance is opposite to the direction of movement, f is negative. The inertial resistance force F1 generated by the accelerated motion is opposite to the direction of acceleration, and the direction of acceleration is positive, so F1 is negative. Similarly, the resultant force of all force elements is 0, that is, Ff-F1-F0=0, so the value of the user's pulling force F0 is F0=Ff-F1, that is, F0=Ffm×a.

[0029] The above two states can be summarized as the following formula: F0=Fm×a+dir×f (1).

[0030] Where: F0 is the actual output force of the user, m is the equivalent mass of the load component in the displacement direction, a is the acceleration of the load component in the displacement direction, f is the resistance of the system in the displacement direction, F is the output force of the force generating device, dir takes +1 when the movement direction is positive and takes -1 when it is negative.

[0031] The present invention does not consider the calculation of system resistance in specific equipment, which is usually the friction resistance or pulley rolling resistance in the system. Because the judgment in this article is in the hands-free (no-load) state, its resistance value can be generated by the force generating device under no-load conditions. A uniform return movement and the required force value is recorded as the system resistance f. Different specific equipment can obtain a fixed resistance f or a resistance f(x) that changes with condition x through different test methods.

[0032] like Figure 5 As shown in the figure, the user force F0 calculated by formula (1) is the user force waveform change during normal exercise within 8 seconds after starting. According to the calculation, the force drop curve from the 8th second to the 10th second is the force drop curve after the user lets go. The fluctuation after the 10th second is the fluctuation generated when the load component reaches the limit of the limiter.

[0033] S5. The control system includes at least one processor for executing real-time data processing and control logic, monitoring the actual output force of the user in real time, and determining that the hands-off state occurs when the actual output force of the user drops to zero. S6. After the hands-off state is detected, the output force of the force generating device is adjusted so that the return speed of the load component is within a safe range.

[0034] The method for controlling the output force of the force device after the hands are released is applicable to all training equipment that controls speed by force. Specifically, during the return movement, the output force of the force device provides a safe return pulling force. The safe return pulling force is dynamically controlled and a maximum safe return pulling force is set as an upper limit. The safe return speed of the load component is controlled by adjusting the output force of the force device. The adjustment range of the safe return speed is the minimum return speed and the maximum return speed.

[0035] The maximum safety return tension is the tension when the load component is returned to stop. The maximum safety return tension is assigned different tension values ​​according to different equipment. The maximum safety return tension Fs_max, the safety return tension Fs, the safety return speed Vs, the minimum return speed Vs_min and the maximum return speed Vs_max satisfy the following variable relationship: k=(Vs-Vs_min) / (Vs_max-Vs_min) (2) Fs=Fs_max×(1-k) (3)

[0036] like Figure 6 As shown in Figure 1, from the 8th to the 10th second, when the user lets go of the load, the acceleration curve of the load component (blue line) rises sharply, and the user force (yellow line) calculated according to formula (1) drops rapidly to 0 (9.28 seconds). After the user force drops to 0, the control system quickly (9.32 seconds) reduces the output force (red line).

[0037] The reason why the value is less than 0 at 9.28 seconds is that the rope of the test equipment is elastic. When the rope is pulled out of the hands, it contracts, causing the rope to be temporarily loose on the reel. That is, the equivalent mass m′ pulled by the force device is less than m at this time. At this time, the actual output force F0 of the user is 0. F is the constant force of the force device before the hands-off protection control. Therefore, according to formula (1), the affected variable is F1=m×a=F±f. According to formula (1), the actual acceleration a′=(F±f) / m′ can be obtained. Substituting it into formula (1) of the program, F0=F±fm×(F±f) / m′=(F±f)×(1-m / m′) is obtained. Because m′ is less than m, it is less than 0 before the rope is straightened (that is, m′=m). The equipment reacted quickly within 0.04 seconds, and its error result does not affect the final judgment of formula (1).

[0038] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention shall be defined by the attached claims and their equivalents.

Claims

1. A method for controlling a hand-off protection of an electric-controlled strength training device, characterized in that: The specific steps include: S1. Using a speed measuring device to collect displacement speed data of a load component in real time; S2. Calculate the acceleration of the load component based on the collected displacement velocity data; S3, calculating the force exerted on the load component by combining the acceleration with the equivalent mass of the load component; S4. Determine the actual output force of the user according to the force applied to the load component, the system resistance, and the output force of the force generating device; S5, real-time monitoring of the user's actual output force, when the user's actual output force drops to zero, it is determined to be a hands-off state; S6. After detecting the release state, adjust the output force of the force generating device so that the return speed of the load component is within a safe range.

2. The method for preventing a hand from slipping out of an electric-controlled strength training device according to claim 1, characterized in that: The speed measuring device is installed at the output end of the force generating device and is used to measure the output speed of the force generating device and the displacement speed of the load component.

3. The method for preventing a hand from slipping out of an electric-controlled strength training device according to claim 1, characterized in that: The force generating device includes but is not limited to a servo motor, a controllable force pneumatic cylinder or a controllable force hydraulic cylinder.

4. The method for preventing a hand from slipping out of an electric-controlled strength training device according to claim 1, characterized in that: The step S4 satisfies the following formula: F0=Fm×a+dir×f; Where: F0 is the actual output force of the user, m is the equivalent mass of the load component in the displacement direction, a is the acceleration of the load component in the displacement direction, f is the resistance of the system in the displacement direction, F is the output force of the force generating device, dir takes +1 when the movement direction is positive and takes -1 when it is negative.

5. The method for preventing a hand from slipping out of an electric-controlled strength training device according to claim 1, characterized in that: The control method of the output force of the force generating device in step S6 is as follows: during the return movement, the output force of the force generating device provides a safe return pulling force, the safe return pulling force is dynamically controlled and a maximum safe return pulling force is set as an upper limit, and the safe return speed of the load component is controlled by adjusting the output force of the force generating device, and the adjustment range of the safe return speed is a minimum return speed and a maximum return speed.

6. The method for preventing a hand from slipping out of an electric-controlled strength training device according to claim 5, characterized in that: The maximum safe return tension is the tension when the load component is returned to stop, and the maximum safe return tension is assigned different tension values ​​according to different equipment.

7. The method for preventing the electric-controlled strength training apparatus from slipping out of the hands according to claim 5, characterized in that: The maximum safety return tension Fs_max, the safety return tension Fs, the safety return speed Vs, the minimum return speed Vs_min and the maximum return speed Vs_max satisfy the following variable relationship: k=(Vs-Vs_min) / (Vs_max-Vs_min) Fs=Fs_max×(1-k).

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