RU1836971C - Device to determine the length of ski jumping - Google Patents

Abstract

The invention relates to devices for controlling sports events and can be used to measure the length of an athlete's ski jump. The aim of the invention is to increase the accuracy of determining the length of the jump. This is achieved by the fact that the device comprises a block for fixing the moment of landing, made in the form of seismic sensors located along the central axis of the springboard and connected in parallel with each other, a tracking system for the movement of the athlete, which consists of a source of magnetic field, for example, a constant a magnet mounted on the athlete’s equipment, and rows of magnetic receivers located on the springboard, in its surface layer, at equal distances from each other, perpendicular to the central axis of the mountain Yeni. Each row of magnetic receivers contains an even number of magnetic receivers connected in parallel with each other. The unit for fixing the moment of landing and the tracking system for tracking the athlete's movement are connected respectively to the signal preprocessing unit, which is connected to the display unit. 1 s.p. f-ly. next to

Description

The invention relates to devices and accessories for monitoring sports events and a training process and can be used to measure the length of a ski jump.

The aim of the invention is to increase the accuracy of determining the length.

This is achieved by the fact that the device for determining the length of ski jumping from a springboard comprises a landing fixation unit made in the form of seismic receivers located along the central axis of the landing mountain and connected in parallel with each other, an athlete’s tracking tracking system designed as a magnetic field source, installed on skis or equipment of an athlete, and rows of magnetic receivers placed on the landing springboard at equal distances from each other, perpendicular to its central axis, each row contains an even number of magnetic receivers connected in parallel with each other, and the landing block and the tracking system for tracking the movement of the athlete are connected

C)

oh yu vj

responsibly to the signal preprocessing unit connected to the display unit.

The goal is also achieved by the fact that the signal preprocessing unit is made in the form of an amplifier — a shaper of signals of seismic sensors, amplifiers — shapers of signals of magnetic receivers, the number of which is equal to the number of rows of magnetic receivers, three shapers, an OR circuit, five circuits AND, two RS-flip-flops, a counting flip-flop, a pulse generator, two counters, a register number of a number of magnetic receivers, a zero-setting device and the corresponding connections between them.

The essence of the device is as follows.

It is known that after an athlete lands, his speed of movement along the landing mountain remains practically constant for a certain time, depending on the properties of the springboard. The moment of landing is recorded using seismic receivers that receive the surface shock wave that occurs when the athlete lands. Using the tracking system for moving the object, the signal preprocessing unit, and the display unit, the time elapsed from the moment of landing to the intersection of the athlete is recorded along its movement of a series of magnetic receivers, and the value of the time elapsed from the moment of crossing the first along the movement of a series of magnetic receivers to the moment of crossing a series of magnetic receivers following it. By knowing the time taken by the athlete to travel a certain distance, the speed of the athlete’s movement after landing can be calculated. From the value of the speed and the measured travel time from the moment of landing to the intersection of the first along the line of motion of the magnetic receivers, one can determine the distance from the place of landing to the first along the line of magnetic receivers. The length of the jump is determined by the difference between the distance from the breakaway table to the first along the movement of the series of magnetic receivers and the measured distance from the landing site of the athlete to this series.

The athlete’s passage of the landing mountain section, at which his speed is practically constant, is recorded with the help of magnetic receivers installed in this section and receiving a signal from a magnetic field source placed on the athlete’s ski. The magnetic receivers are connected to a signal preprocessing unit, which is also connected to the output of the landing block. The display unit associated with the signal preprocessing unit is intended to obtain visual information allowing the calculation of the jump length without a computer.

A comparative analysis of the proposed solution with the prototype shows that the claimed device is characterized by the presence of new features: a new embodiment of the landing block, a new embodiment of the tracking system for the movement of the athlete, a new embodiment of the signal preprocessing unit and new communications between the units of the device.

A device for determining the length of ski jumping from a springboard includes a block for fixing the moment of landing, a tracking system for tracking the athlete's movement, connected to the corresponding inputs of the signal preprocessing unit, connected to the display unit.

The block for fixing the moment of landing consists of seismic receivers located in the surface layer of the mountain of landing along its central axis and connected in parallel with each other. The tracking system of the athlete’s movement is made in the form of a magnetic field source, for example, permanent magnets mounted on the athlete’s skis or his equipment, and rows of magnetic receivers located in the surface layer of the landing mountain at equal distances from each other. Rows of magnetic receivers are located perpendicular to the central axis of the landing mountain.

The signal preprocessing unit comprises an amplifier-driver of signals of seismic sensors, the inputs of which are connected to the outputs of the unit for recording the moment of landing and amplifiers-drivers of signals of magnetic receivers, the number of which is equal to the number of rows of magnetic receivers, whose inputs are connected to the outputs of the tracking system for tracking the athlete's movement. The output of the amplifier-driver of the signals of the seismic sensors through the driver is connected to the input of the installation of the first RS-trigger. The reset input of the RS-flip-flop is connected to the output of the first AND circuit, and its direct output is connected to the first input of the second And circuit, the output of which is connected to the counting input of the first counter (binary decimal counter). The outputs of the first counter are connected to the display unit. The outputs of the amplifiers-shapers of the signals of the series of magnetic receivers are connected to the inputs of the OR circuit and to the inputs of the register of the number of the series of magnetic receivers, the outputs of which are connected to the display unit. The output of the OR circuit through a former is connected to the first input of the third AND circuit, the second input of which is connected to the direct input of the second RS flip-flop. The output of the third AND circuit is connected to the second input of the first And circuit, and to the counting input of the counting trigger, the direct output of which is connected to the first input of the fourth And circuit, and its output with the counting input of the second counter (binary decimal counter), the outputs of which are connected to the display unit. The inverse output of the counting trigger through the driver is connected to the first input of the fifth AND circuit, the output of which is connected to the reset input of the RS trigger, the installation input of which is connected to the output of the driver. The second input of the first AND circuit, the reset inputs of the counting trigger, the first counter, the second counter, the second input of the fifth AND circuit, the reset input of the number register are connected to the initialization device. The second inputs of the second circuit And, the fourth circuit And are connected to the output of the pulse generator.

The signal preprocessing unit can be performed on K 155, K555, K 140 series microcircuits.

The display unit contains two decoders, the inputs of which are connected to the outputs of the signal preprocessing unit, and their outputs with the corresponding inputs of the indicators. The anodes of the LEDs, which are also included in the display unit, are connected to the corresponding outputs of the signal preprocessing unit, and their cathodes with a common bus.

The display unit can be performed on K 154 series microcircuits, LED matrixes can be of the ALS324 type, LEDs can be AL 307 ..

The amplifier-driver of the signals of the seismic sensors and the amplifier-driver of the signals of the magnetic receivers are made according to the same scheme and contain each input filter, the inputs of which are connected to the output of the unit for fixing the moment of landing, and the output of the filter is connected to the input of the amplifier, the output of which is connected to input of a differentiating amplifier. The output of the amplifier is connected to the input of the threshold device. The amplifier-shaper can be made according to well-known schemes, for example, on K 140 series microcircuits. The sensitivity of the amplifier-shaper is about 0.5 mV, the bandwidth is 5 ... 30 Hz, the gain is determined by the ratio of the resistors of the amplifier depending on the types of amplified signals (from seismic receivers or from magnetic receivers). The threshold of the threshold device is determined by seismic and electromagnetic signal / noise ratios and is set by the corresponding adjusting elements in the circuit.

As already mentioned above, the landing fixation unit consists of several seismic receivers, which can be used as sensors type SV-10 GOST16810-71. Seismic receivers are installed in the surface soil layer of the touchdown mountain (under snow or under artificial cover) along the central axis of the touchdown mountain and are connected in parallel with each other. The number of geophones depends on the properties of the springboard. The distance between them depends on the propagation velocity of longitudinal elastic waves in the soil (in the worst case, if the landing mountain consists of sandstone, the wave propagation speed is from 2.5 to 7 µ / s; if the mountain is made of concrete, the wave propagation speed is higher). According to the results of studies, a device with a single seismic receiver records the moment of landing of an athlete weighing 40 kg at a distance of not less than 35 m.

In order to reduce the likelihood of a false response from seismic interference, the response level of the threshold device of the driver amplifier is established after examining the seismic situation on the landing mountain and is selected 3 times higher than the amplitude of the maximum interference emissions in the measured signal; After setting the threshold level of the threshold device, the maximum distance at which the device reliably fixes the moment of landing of the jumper is determined. If this distance is, for example, 25 m, then the maximum distance between geophones for a springboard of 90 m with a landing mountain width of about 10 m will be approximately 48 m. To increase the reliability of fixation, you can take a distance between geophones of 25 ... 30 m. Then, for a 90-meter springboard with a length of a landing section of about 70 m, 3-4 geophones will be required.

The athlete’s tracking system consists of a magnetic field source and rows of magnetic receivers mounted on a landing mount, perpendicular to its central axis and at equal distances from each other. Permanent magnets with high magnetic properties, which are mounted on an athlete’s equipment, such as skiing, can be used as a magnetic field source.

On the recommendation of technical experts on ski jumping, the weight of the magnet should not exceed 50 g, and its dimensions should not interfere with the athlete. Such a source of magnetic field can be a magnet made of material UN14DK24 GOST 17809-72, made in the form of a washer with a diameter of 30 mm m, 2 mm thick.

Rows of magnetic receivers are installed on the landing mountain at such distances from each other at which the athlete's speed of movement does not change by more than 2%. Rows of magnetic receivers are installed at equal distances from each other, the number of rows must be at least three. Thus, for example, for 70 to 90 meter jumps, the length of the section with a uniform speed is at least 20 m (at a minimum speed of 10 m / s). Thus, three rows of magnetic receivers with a distance of 10 m between them are installed in such a section. In principle, each series of magnetic receivers can be an inductor with a core length of approximately the width of a springboard. However, such a construction is not technologically advanced and inconvenient during transportation and installation. Therefore, it is advisable that each row of magnetic receivers be made in the form of an even number of magnetic receivers, which are coils with cores connected in parallel and in pairs to counter natural and industrial interference. Magnetic receivers are installed under artificial cover at a depth of 50-100 mm, and taking into account the snow cover, the depth of the magnetic receiver can reach 600 mm.

A device for determining the length of ski jumping from a ski jump operates as follows. Before starting work, the triggers, register, counters are set by the device to the zero state in state 0. At the same time, the direct outputs of the triggers set logical O and the second and third circuits AND are closed. on the first input, and the fourth circuit And on the second input, and signals to the corresponding inputs of the trigger and the first and second counters are not received. The output signal of the geophones, arising from the impact at the moment the athlete lands, passes through the driver amplifier and the driver sets the first and second RS triggers to logic 1 on their direct outputs. In this case, a second circuit And opens through the first input, through which pulses with

generator output, and the second input - a third circuit I.

When an athlete crosses the nearest row of magnetic receivers at the moment when the athlete crosses the axis p 0 and the magnetic receivers, the signal amplitude reaches its maximum value, and the value of its derivative at the output of the differentiating amplifier passes through O, the threshold device is amplified by a 5 l-former, and its output the signal sets a high potential in the register bit corresponding to the crossed row of magnetic receivers, and the corresponding LED lights up

0 display unit. The output signal of the amplifier-former is simultaneously supplied to one of the inputs of the OR circuit, and its output signal, passing through the former, the third circuit And, is fed to the first input of the first circuit And, setting the first RS-trigger to its original position. In this case, the low level at its direct output closes the second circuit And at the first input, stopping the supply of pulses from

0 generator to the first counter. The signal from the output of the third circuit And also goes to the counting input of the trigger, setting a high potential at its direct output, which, entering the first input of the fourth

5 of circuit And, opens it, and pulses from the output of the generator pass to the input of the second counter.

When the athlete crosses the next row of magnetic receivers, the output signal of the amplifier-former, passing through the OR circuit, the former, the third AND circuit, sets a low potential at the direct output of the trigger. At the same time, the first input of the fourth AND circuit is closed, and the supply of pulses to the input of the second counter is stopped. A positive edge of the signal from the inverse output of the trigger through the driver and the fifth circuit And sets a low potential at the output of the second RS-trigger, which closes the third circuit And at the second input, blocking the passage of pulses from the output of the amplifier-former, arising from the intersection of the next Dov

5 magnetic receivers.

This completes the preparation of information for calculating the length of the jump. The first counter contains the number of gi proportional to the time the athlete moves from the moment of landing to

crossing the first downstream athlete in a series of magnetoreceivers. The second counter contains the number П2 proportional to the time of the athlete's movement from the moment of crossing the first along the row of magnetic receivers to the moment of crossing the next row.

To provide greater information in obtaining the result of measuring the length of the jump and the convenience of drawing up competition protocols, a personal computer can be connected to the inputs of the counters and the outputs of the register through the corresponding interface unit.

The jump length L is calculated by the following formula

lunge, and equal to 0. if landing without lunge;

K 0.3;

K - taken equal to 0.3, based on the following; typically, the athlete’s lunge length during landing is between 0.5 and 0.6 m. Half of this distance is approximately 0.3 m.

Substituting (3) in (2), we obtain

i - i. KI m. ni

41 - I G.I

Kl P2P2

(4)

Substituting the value ln (4) in (1), we obtain the final formula for calculating the length of the jump

L h + l2 (N- 1) -ln- M K,

where I is the distance from the separation table to the first row of magnetic receivers, m (numbering is from the series closest to the separation table);

I is the distance between the rows of magnetic receivers, m;

N is the number of the nearest (first) row of magnetic receivers crossed by the athlete;

In is the distance from the landing site to the nearest (first) row of magnetic receivers crossed by the athlete in the direction of travel.

ln V ti, V -, 1n Г -, t2t2

where V is the speed of the athlete after landing;

ti is the travel time from the point of landing to the nearest along the line of magnetic receivers;

T2 — travel time between the closest in the vicinity of the house and adjacent to it series of magnetic receivers (in the direction of movement of the athlete);

t1 Kl W, t2 KG P2,

where u is the information recorded in the first block counter;

 - information recorded in the second block counter;

Ki is the proportionality coefficient depending on the frequency of the generator output pulses;

Ki 1 / f, where f is the frequency of the generator;

M - coefficient equal to 1 if the judges recorded the athlete’s landing with

L li + | - (N- 1) -l

twenty

. ni

P2

M K.

(5)

25

thirty

35

Examples of calculating the length of an athlete's ski jump.

Initial data:

Trampoline 90 m

H 30m

1 8 m

the number of rows of magnetic receivers is 11.

Example 1. An athlete landed between the second and third rows of magnetic receivers.

N 3

M -1 - lunge jump recorded

Щ 520

P2 1760

from (5)

 + | - (N- 1) - --M K

P2

40 45

fifty

L 30 + 8- (3-1) -8 Example 2 m 360 P2 888 N 9 M 0

L 30 + 8 (9 - 1) - 8

520 1760

-0.3 4m

360 888

90.5m

When conducting training jumps, the speed value at the time of landing may be needed.

,

t1Kl P2

f 1 3000 Hz,

P2

ft, V

8 x 3000 888

 27 m / s

Compared with the prototype, the proposed device for determining the range of the jump has a simpler design, increased reliability, can be used in any weather conditions, which is explained as follows.

The landing fixation block of the proposed device consists only of seismic sensors located on the landing mountain, connected in parallel, the response signal for which is the athlete’s impact on the surface of the landing mountain, which eliminates the need for contact devices, a radio , a power source, an electronic circuit fixed to the athlete and causing a lack of reliability of the prototype device. Adverse weather conditions can also affect the operation of the prototype landing block, which will not affect the operation of the landing block of the device of the invention.

As for the athlete’s tracking system, increasing the reliability of its operation is related to the fact that its movement is not affected by soil movements, meteorological conditions that reduce the reliability of the tracking system of the prototype device.

Claims (2)

1. Device for determining the length. Ski jumping, comprising a block for fixing the moment of landing, a tracking system for tracking an athlete connected to a signal processing unit connected to a display unit, characterized in that, in order to increase the accuracy of determining the length, the locking unit the moment of landing is made in the form of seismic receivers located in the surface layer of the springboard along its central axis and connected in parallel, the tracking system for the movement of the athlete is made in the form of chnika magnetic field, mounted on the projectile zhenii athlete and magnetic nitopriemnikov placed in the surface layer jump at equal distances from each other perpendicularly its central axis, with each row containing an even number of magnetic receivers connected in parallel. 2. The device according to p. 1 ,. The fact is that the signal processing unit contains amplifiers-shapers of signals of seismic sensors and magnetic receivers, shapers, circuit OR, AND, RS-triggers, counting trigger, pulse generator, counters, number register a series of magnetic receivers, a reset device to the zero state, while the inputs of the driver amplifiers are the inputs of the signal processing unit, the output of the first amplifier driver is connected to the inputs installation of the first and second RS-flip-flops, and the outputs of the remaining amplifiers-shapers are connected to the register number of the number of magnetic receivers and the OR circuit, the output of which through the second shaper is connected to the first input of the first circuit AND, the output connected to the counting input of the counting trigger and the first input of the second circuit And, with the output connected to the reset input of the first RS-trigger, my output is direct which is connected to the first input of the third circuit And, the second input of which is connected to the pulse generator, the output of the third circuit And is connected to the counting input of the first counter, and the inverse output of the counting trigger is connected through the third driver to the first input of the fourth circuit And, the output connected to the reset input second RS-flip-flop, whose direct output is connected to the second input of the first AND circuit, and the direct output of the third counting trigger is connected to the first input of the fifth AND circuit, the second input of which is connected to the pulse generator, and the output to the counting input of the second counter, the output of the zeroing device is connected to the reset inputs of the counters, register and second inputs of the second and the fourth circuit And, and the outputs of the counters, the register number of the series of magnetic receivers are the outputs of the block signal processing.