CN108096809A - Taiji push hands training two-dimensional force measurement platform - Google Patents

Abstract

The invention relates to a two-dimensional force measuring platform for Tai Chi pushing hands training, comprising: a platen (1), a beam (2), a tension and pressure sensor (7), two guide rails (3), four guide rail sliders (4), And four electronic weighing sensors (8), four electronic weighing sensors are fixed on the four ends of the guide rail; a crossbeam is installed between the ends of the two secondary guide rails, the crossbeam is perpendicular to the guide rail, and the tension and pressure sensors are installed on the crossbeam Between the platen and the platen; two connecting pieces respectively connect the beam and the tension-compression sensor, and the platen and the tension-pressure sensor; the guide rail is a sliding guide rail of a cylindrical track, and the slider of the sliding guide rail is fixed to the platen. The present invention uses ordinary electronic weighing sensors to measure the force up and down, uses S-type tension and pressure sensors to measure the force before and after, and realizes force decoupling through a mechanical device, which ensures the accuracy and precision of force measurement and is suitable for popularization by the public.

Description

Two-dimensional force plate for Tai Chi pushing hands training

Technical field:

The invention relates to a two-dimensional force measuring platform for Tai Chi pushing hands training and a pushing hands testing and training method.

Background technique:

As a unique fitness exercise in my country, Tai Chi has rich connotations and technicalities. At present, it is mainly known to fans and the world in the form of boxing. However, the most indispensable part of traditional Tai Chi, the methods and key points of Tai Chi Push Hands are rarely known. The main pushing mistakes are:

1. Emphasize the martial nature of Taijiquan and Push Hands. In order to achieve the effect of pushing the opponent out, Taijiquan uses penetrating force and internal strength instead of muscle strength, and blindly increases force when the center of gravity is tilted.

2. To mystify Taijiquan, under the suggestion in my heart, use methods that do not conform to the principle of mechanics (conservation of momentum) to send partners a long distance.

3. Ignoring Taijiquan's characteristics of sticking and sticking, not throwing or topping, and sending out the opponent through the inertial force of moving steps or forward rushing.

Claims 6 and 7 can help fans make scientific guidance on the training process of pushing hands. However, the existing force plates currently on the market, such as Kistler force plates in Switzerland and AMTI in the United States, are all 6-dimensional force plates, which require 6-dimensional force sensors as force-measuring components and are expensive. It is not suitable as sports equipment for the popularization of national fitness.

The present invention studies a two-dimensional force measuring platform. The biggest difficulty involving multi-dimensional force measurement is how to solve the problem of decoupling the six degrees of freedom of space objects. The advanced multi-dimensional force measuring element is also to deal with this problem, which makes the design and processing technology of the sensor very duplicated, and the difficulty and cost of preparation are increased.

Invention content:

The invention provides a means capable of quantitatively analyzing the process of Tai Chi pushing hands. The two-dimensional force plate for Tai Chi pushing hands training is characterized in that it includes: a platen (1), a beam (2), a tension and pressure sensor (7), two guide rails (3), and four guide rail sliders (4) , and four electronic weighing sensors (8), four electronic weighing sensors are fixed on the four ends of the guide rail; a crossbeam is installed between the ends of the two pairs of guide rails, the crossbeam is perpendicular to the guide rail, and the tension and pressure sensors are installed on the between the crossbeam and the table; two connectors respectively connect the crossbeam and the tension-pressure sensor, and the platen and the tension-pressure sensor; ) and/or the electronic weighing sensor (8) can adopt a 1-dimensional sensor. The present invention can use a 1-dimensional sensor to realize 2-dimensional force measurement instead of a multi-dimensional sensor. The tension and compression forces in the front-to-back direction are decoupled from the forces and torques in the other degrees of freedom by mounting the sliding guides of the cylindrical rails.

The specific method of data acquisition is as follows:

(1) The S-type tension and pressure sensor measures the front and rear forces of the measured object during its movement.

(2) The electronic scale load cell measures and obtains the magnitude of the up and down force of the measured object during its movement.

(3) Through the host computer, the data of the measured force is collected at a period of 0.01S, and displayed on the interface in the form of a curve. to obtain time information.

In order to make the training equipment of Tai Chi push hands more suitable for the needs of the whole people's fitness and the popularization of Tai Chi movement, the present invention provides a relatively simple and reliable two-dimensional force measurement method, including: a platen, which is a rectangular parallelepiped plate; pressure sensor; two pairs of guide rails and four guide rail sliders; two connectors connecting the beam, platen and tension and pressure sensors.

The invention adopts a weighing sensor for an electronic scale and an S-type tension and pressure sensor for industry instead of a multi-dimensional force sensor, which simplifies the data collection and processing process and reduces the cost.

The invention draws lessons from the principle that the train track constrains the movement of the train in the direction of the track, constrains the movement of the force measuring platform in one direction through two parallel guide rails, and then measures the force in the direction. It effectively shields the force and torque in other directions from interfering with the force measurement in this direction, and realizes force decoupling through the mechanical structure, so as to obtain force data in the front and rear directions.

In terms of the selection of the guide rails of the force measuring platform, a cylindrical rail is selected instead of an I-shaped rail, so that the measurement loss of the front and rear force due to the micro deformation of the table is avoided when measuring the front and rear force.

The force measuring platform fixes the load cells at the four ends of the guide rails, respectively obtains two sets of gravity values in the form of a half-bridge circuit, and finally obtains the force in the vertical direction.

The table top of the measuring table is fixed to one end of the tension-compression sensor, the beam is fixed to the guide rail, and the other end of the fixed tension-compression sensor is placed parallel to the two guide rails.

The technical solution of the present invention has the following advantages:

The invention evaluates the process of Tai Chi pushing hands in a quantitative manner by measuring the plantar force. It can effectively help Tai Chi enthusiasts to correctly grasp the essentials of pushing hands. The invention adopts a load cell for electronic scales and an S-type tension and pressure sensor for industry, both of which are mature and stable sensor elements on the market, so the cost is low and the measurement process is stable and reliable. The invention adopts the sliding guide rail of the cylindrical track, which restricts other degrees of freedom of the table top, prevents the force and moment of other degrees of freedom from affecting the force measuring element in this direction, and realizes reliable force decoupling.

Description of drawings

Figure 1a is a schematic diagram of the present invention.

Figure 1b is a side view of Figure 1a.

Detailed ways:

One of the evaluation method examples of pushing hands training in the present invention:

(1) Send an adult about 60 kg over a distance of more than 2 meters, and the up and down force is greater than 50N, and lasts for more than 0.1S, then the force is applied to the feet. If the time difference between the front and rear force and the up and down force is smaller, it is determined that the force of the sender is more integrated.

(2) If an adult about 60 kg is released at a distance of more than 2 meters, and the up and down force is less than 50N, the opponent will be pushed out by inertial force or the force of the body leaning forward and losing the center of gravity, which needs to be improved.

(3) When an adult about 60 kg is released at a distance of more than 2 meters, and the front, rear and up and down forces are both less than 50N, it is determined that the sender is using muscle force or fake pushing (that is, the partner being released uses a cooperative technique).

In order to obtain the effect of (1) in the evaluation method, push hands trainers need to relax their whole body according to the body method of Taijiquan. There is no stagnant force on the body, so that the internal strength between the feet and hands can be directly connected through the hub function of the waist. When exerting force, keep standing upright, do not step forward, do not lean forward, and use less muscle power. Practice repeatedly to obtain feedback data, so as to continuously improve skills under the guidance of the evaluation system.

The two-dimensional force plate among the present invention needs in implementing: platen, is cuboid plate; Beam, connects tension and pressure sensor and guide rail; Two pairs of guide rails and four guide rail sliders; tension sensor.

According to the force characteristics of the measured object in the process of pushing hands, the measuring range of the weighing sensor in the present invention is 400KG, the measuring range of the S-type tension and pressure sensor is 100KG, and the precision is 1N.

During the implementation, the guide rail sliders are arranged as far as possible separately and fixed at the lower part of the platform to prevent the subject from standing on the edge and causing the platform to overturn.

Two pairs of guide rails go through the slider to fix the beam under the two guide rails. The distance between the top of the beam and the bottom of the platen is greater than and close to the thickness of the S-type tension-compression sensor. Under the premise of leaving the installation space for the sensor, try to control the total height of the force plate.

A connecting piece with a semicircular groove is fixed on the beam, the groove is upward, and the arc of the groove is larger than and close to the diameter of the sensor mounting bolt.

A connecting piece with a semicircular groove is fixed under the platen, the groove is downward, and the arc of the groove is larger than and close to the diameter of the sensor mounting bolt. The installation position of the connector is determined by the position of the beam groove and the length of the sensor.

The S-type tension and pressure sensor is fixed between the beam and the platen by nuts. When installing, try to ensure that it is parallel to the direction of the table top and the guide rail, so as to improve the accuracy of measuring the force before and after.

Four load cells are fixed at the four ends of the guide rail. When each load cell is installed, a spacer needs to be added between its top and the bottom of the platen, and a spacer needs to be added between its bottom and the ground. Guarantee its force-measuring structure.

The force measuring element responds to the change of the output force through the change of the resistance value. Therefore, the force acquisition system needs a half-bridge or full-bridge circuit, and an analog-to-digital conversion module to collect the real-time value of the force into the single-chip microcomputer and upload it to the host computer.

Claims (4)

1. Taiji push hands training two-dimensional force measurement platform, which is characterized in that including：

Platen (1), crossbeam (2), a tension-compression sensor (7), two secondary guide rails (3), four guide rail slide blocks (4) and four electronics Claim sensor (8), four electronic scale sensors are fixed on four ends of guide rail；

One crossbeam is installed between the end of two secondary guide rails, which is mounted on crossbeam in guide rail by tension-compression sensor Between platen；Two connector difference connecting cross beams and tension-compression sensor, platen and tension-compression sensor；Guide rail is cylindrical rail The rail plate in road, sliding block and the platen of rail plate are fixed.

2. ergograph according to claim 1, it is characterised in that：Tension-compression sensor (7) and/or electronic scale sensor (8) are adopted With 1 dimension sensor.

3. ergograph according to claim 1, it is characterised in that：By installing the rail plates of cylindrical tracks by front and back To pulling force and the power and torque of pressure and other degree of freedom decouple.

4. the method for application ergograph as described in claim 1-3 any one, it is characterised in that：Testee stands in ergograph On, granting action is done on the dynamometry direction of ergograph, ergograph shows and records front and rear and bearing up-down force numerical value；

Tension-compression sensor measurement obtains the size of measurand front and rear power during the motion；

Electronic scale sensor measurement obtain measurand during the motion on the size exerted oneself；

Upper computer software is gathered by the data of dynamometry using 0.01S as the cycle, and is shown in graph form on interface；It is adopting After collection process, complete data are preserved by file；Obtain the relation curve of power and time.