Multi-beam laser complex and method for interactive hit registration

Abstract

FIELD: interactive gaming and training systems; laser hit detection systems.SUBSTANCE: method for interactively registering hits with a sports projectile involves limiting a flat scanning area and projecting an interactive image onto it. The area is scanned using near infrared radiation using two laser units. Before scanning, the laser radiation from each block is split into a fan of planes consisting of 2–64 beams with a pitch of 0.5 to 5 cm. The coordinates of the projectile are calculated using triangulation. The obtained coordinates are compared with the target position and “hit” or “miss” signals are generated. To implement the method, a complex for interactive registration of hits by sports equipment is proposed, containing a display device, a computer and two laser scanning units. Each unit includes a continuous near-IR laser, a beam splitter, a harmonic modulation generator, a controlled optical scanner, and a receiving path with a narrow-band filter. The computer is designed with the ability to perform triangulation calculations and generate control video signals.EFFECT: increase in the probability of detecting a projectile.9 cl, 4 dwg

Description

[0001] Technical field

[0002] The invention relates to interactive gaming and training systems, in particular to laser hit detection systems for amusement parks, sports training equipment (football, hockey, handball, darts), military-applied training equipment (paintball, airsoft), as well as for training in team sports.

[0003] Technology Level

[0004] Various hit detection systems are known from the prior art.

[0005] Analogue 1: Laser shooting ranges with beam interruption (beam-receiver).

[0006] In such systems, several laser beams and corresponding photodetectors are installed along the projectile's path. When the projectile intersects the beam, the beam is detected. Disadvantages: precise alignment of the source and receiver is required, low spatial resolution, inability to determine precise impact coordinates, and limited coverage area.

[0007] Analogue 2: Video systems with cameras and computer vision.

[0008] Cameras record the projectile's trajectory and determine whether it hits. Disadvantages: image processing lag (tens to hundreds of milliseconds), dependence on external lighting, difficulty processing high-speed projectiles (airsoft bullets, pucks), and high cost of computing equipment.

[0009] Analogue 3: Sensors on targets (accelerometers, piezoelectric elements).

[0010] When a projectile hits the sensor, it registers the impact. Disadvantages: Requires physical contact, limited lifespan, false alarms, and cannot be used with soft projectiles (foam balls).

[0011] Analogue 4: Single scanning beam laser systems.

[0012] Systems using a single laser beam scanning an area are known. Disadvantages: low detection probability for high-speed, small-caliber projectiles, as the projectile travels a distance significantly greater than the beam width during a single scan period. Reliable detection requires a scanning frequency of 10 kHz or higher, which significantly increases the cost of the system.

[0013] The closest analogue is the Multi-Beam Laser System (patent RU RU2708727C2). The invention relates to a laser system with multi-beam output radiation (variants) and a method for welding workpieces. The system is a multi-fiber laser system delivering output radiation through at least three fibers arranged circumferentially, or the output radiation of at least four separate lasers from a single working cable. The invention makes it possible to control at least three laser modules and deliver their output radiation in a predetermined sequence within a single working cable, thereby enabling multi-stage processing of a workpiece, which previously required a separate optical system for each beam. The output radiation of at least three lasers is optimized for creating spot welds, seam welds, or virtual oscillating welds during seam welding.

[0014] Disclosure of the essence of the invention

[0015] The technical problem that the claimed invention is aimed at solving is the creation of a high-speed hit registration system for working with various types of projectiles (balls, pucks, darts, airsoft and paintball bullets) with a limited scanning frequency.

[0016] The technical result achieved by the claimed invention is:

[0017] 1. increasing the probability of detecting a high-speed projectile at a limited (100-500 Hz) scanning frequency;

[0018] 2. Reducing the requirements for scanning frequency by 10-100 times compared to single-beam systems;

[0019] 3. ensuring the ability to work with small projectiles (caliber 4-6 mm) at speeds up to 100 m / s;

[0020] 4. lack of sensitivity to external illumination due to high-frequency modulation of laser radiation;

[0021] 5. precise determination of the coordinates of the hit by triangulation.

[0022] Pre-define a flat scanning area ranging from 1 to 50 meters. This area can be a screen, wall, goalpost, football goal, hockey goal, dartboard, or other limited surface.

[0023] An interactive image containing at least one moving target is projected onto the specified area using an interactive image display device. The image may contain virtual targets, moving objects, game characters, etc.

[0024] The scanning area is performed using two spatially separated laser scanning units, located on the same side of the scanning area (e.g., below, above, or to the side). The distance between the units (the base) is selected from 0.5 to 5 meters or more, depending on the size of the scanning area.

[0025] The laser beam from each unit is split into multiple beams before scanning, forming a fan of parallel or diverging scanning planes (or lines). The number of beams ranges from 2 to 64. A minimum number (2 beams) already provides an advantage in detection probability compared to a single-beam system, as the projectile crosses the scanning plane twice as often. To ensure guaranteed coverage of the entire scanning area without gaps when working with small projectiles (4-6 mm caliber) at high speeds (up to 100 m / s), 8-16 beams are used. The spacing between adjacent planes in the scanning area ranges from 0.5 to 5 cm, which guarantees that the projectile intersects at least one beam, regardless of its trajectory.

[0026] Each unit emits continuous laser light with a wavelength in the near-infrared range (0.8-1.5 μm), ensuring the beam is invisible to the human eye and safe for vision at a reasonable power level. The laser light is modulated with a harmonic signal with a frequency at least a thousand times higher than the scanning frequency (e.g., a modulation frequency of 50-500 MHz with a scanning frequency of 100-1000 Hz).

[0027] Reception of the reflected signal modulated by the specified frequency is carried out with suppression of unmodulated background interference (sunlight, artificial lighting).

[0028] Each beam is scanned at a frequency of 100 Hz to 1000 Hz. With this scanning frequency and multi-beam configuration, a high-speed projectile (up to 100 m / s) is guaranteed to intersect at least one of the beams, as the distance between adjacent planes is small compared to the distance the projectile travels during the scanning period.

[0029] When a projectile crosses the scanning area, it intersects one or more laser beams. The modulated signal reflected from the projectile is recorded by the receiving paths of each unit. The rotation angles of the scanning beams at the moment of maximum signal are recorded.

[0030] The projectile's coordinates within the scan area are determined by triangulation based on the known ray rotation angles for each block and the known distance between blocks (base). Since the projectile moves in or near a plane, two coordinates (X, Y) are sufficient.

[0031] The received projectile coordinates are compared with the current coordinates of the target (or targets) on the interactive image. If the projectile coordinates fall within the target area within a specified accuracy (e.g., a radius of 1-5 cm), a "hit" signal is generated. Otherwise, a "miss" signal is generated.

[0032] The “hit” or “miss” signal is displayed on the interactive image as a visual effect: flash, animation, text message (“Hit!”, “Miss”), change in target color, explosion of a virtual object, scoring, etc.

[0033] To suppress false reflections from objects outside the scanning area, the scanning area is bordered by a black stripe (or black frame). When no projectile is present, the laser beams hit this black stripe, which has a low reflectivity, reducing the background signal.

[0034] Laser scanning units can be placed on the underside of the scanning area (bottom-up), on the top (top-down), on the side, or a combination of both. The choice of placement is determined by the type of projectile and the game situation.

[0035] Option 1. Corner splitting (from one point).

[0036] The laser beam passes through a diffractive optical element (DOE) or a multiprism splitter, resulting in N beams diverging at small angles relative to each other. The beams cover the entire scanning area without gaps. This option is characterized by simplicity and low cost.

[0037] Option 2. Spatial splitting (parallel rays).

[0038] The laser beam is split using a fiber splitter, and each beam is output through a separate collimator. The beams travel parallel with a fixed pitch Δd (e.g., 1-5 cm). Scanning is accomplished by rotating the entire multi-beam head. This option ensures uniform area coverage and predictable geometry.

[0039] The number of beams (N) is selected in the range from 2 to 64. At N=2, the system already has an advantage over a single-beam system, since two beams, scanning synchronously, double the probability of a projectile intersecting with the beam. However, to ensure continuous coverage of the scanning area without gaps when working with small projectiles, it is preferable to use N from 8 to 16. For particularly demanding applications (e.g., professional sports training equipment), N can be increased to 32-64. The upper limit of N=64 is determined by practical limitations of the cost and complexity of the optical system, as well as the fact that further increasing the number of beams does not provide a significant gain in detection probability.

[0040] The scanning frequency of each beam can be selected from 100 Hz to 1000 Hz. Higher frequencies are possible, but not required, thanks to the multi-beam configuration.

[0041] The complex for implementing the method contains:

[0042] interactive image display device (projector or video panel);

[0043] two laser scanning units spaced at a known distance (base), each unit including:

[0044] Near infrared continuous laser (wavelength 0.8-1.5μm);

[0045] laser beam splitter (DOE, multiprism or fiber splitter) for forming multiple beams (from 2 to 64);

[0046] 50-500 MHz harmonic modulation generator;

[0047] Controlled optical scanner (galvanometer mirror, rotating prism or MEMS mirror);

[0048] receiving path with a narrow-band filter tuned to the modulation frequency;

[0049] A calculator (microcontroller or FPGA) for scanning control, signal reception, triangulation calculation of coordinates and hit / miss signal generation.

[0050] Brief description of drawings

[0051] Fig. 1. General diagram of the multi-beam hit detection system.

[0052] Scan area 7 is shown.

[0053] Bounding frame 4 with black absorbing surface inside.

[0054] Two laser scanning units at the bottom - 1 and 2.

[0055] Scanning beams are emitted from the blocks.

[0056] Projector 3, creating an image.

[0057] Target 6 in the image and projectile 5 in flight.

[0058] Fig. 2. Schematic diagram of the laser scanning unit with a splitter.

[0059] The laser forms a beam that enters the splitter.

[0060] N=2÷64 rays exit the splitter and enter the scanner.

[0061] Scanning is carried out according to the scanning area.

[0062] The modulation generator modulates the laser beam and provides a reference signal for the receiving path with a filter.

[0063] The receiving path receives the reflected signal from the projectile and sends it to the Calculator.

[0064] The computer determines the coordinates and sends the data to the central PC.

[0065] Fig. 3. Principle of triangulation with two blocks.

[0066] Block A and block B at distance L.

[0067] Angles α1 and α2.

[0068] Point of intersection of the projectile with the scanning plane.

[0069] Fig. 4. Multibeam scanning.

[0070] Option 1 - a fan of 4 beams emanating at different angles from scanning unit 1.

[0071] Option 2 - a fan of 4 beams emanating in parallel from scanning unit 1.

[0072] View A (Top view of options 1 and 2 shows scanning area 2).

[0073] Implementation of the invention

[0074] Example 1. Airsoft shooting range (8 beams).

[0075] The scanning area is a rectangular panel measuring 2 x 1.5 m, mounted vertically. The area is bordered by a 5 cm wide black matte frame. An image of moving targets is projected onto the panel.

[0076] Two scanning units are installed underneath, 2 m apart, and facing upward. Each unit contains an 850 nm laser, an 8-beam DOE splitter (angular splitting), a 100 MHz modulation generator, and a 200 Hz scanner. The beams form a fan-shaped pattern of 8 planes intersecting the scanning area at intervals of approximately 2 cm.

[0077] A player fires an airsoft rifle (bullet velocity ~80 m / s, 6 mm caliber). The bullet is guaranteed to cross at least one of the planes. The computer calculates the impact coordinates within 5 ms (accuracy ±1 cm) and compares them with the targets in the image.

[0078] Example 2. Football training machine (16 beams).

[0079] The scanning area is a 7 x 2.5 m soccer goal. Two units are installed below, 5 m apart. Each unit contains a 16-beam splitter (spatial splitting with a 5 cm increment), with a scanning frequency of 100 Hz. A ball (speed up to 30 m / s) crosses the goal, and the system determines the impact zone.

[0080] Example 3.

[0081] For slow projectiles (up to 10 m / s) and large calibers (balls, pucks), two beams are sufficient. The system operates on the same principle, but the detection probability is lower than that of a multi-beam system, but still higher than that of a single-beam system.

[0082] Example 4. Darts (4 beams).

[0083] The scanning area is a circular panel with a diameter of 0.5 m. Blocks are mounted on the side. The beams are split into four beams, spaced 2 cm apart, to ensure coverage of the entire target. The player uses standard darts. When a hit is made, the system determines the hit zone on the panel ("bullseye," "20").

Claims

1. A method for interactively registering hits by a sports equipment, characterized in that the area of ​​impact by the sports equipment is laser scanned, the reflected signal is received, and the coordinates of the sports equipment are determined, characterized in that: a flat scanning area is limited to dimensions from 1 to 50 m; an interactive image containing at least one moving target is projected onto said area; scanning is performed using two spatially separated laser scanning units located on one side of the scanning area; the laser radiation of each unit is split before scanning into a plurality of beams that form a fan of scanning planes; the number of beams is selected in the range from 2 to 64; the step between adjacent planes in the scanning area is from 0.5 to 5 cm; each laser unit emits continuous laser radiation with a wavelength in the near infrared range;laser radiation is modulated by a harmonic signal with a frequency at least a thousand times higher than the scanning frequency; the modulated signal is received with suppression of unmodulated background interference; the coordinates of a projectile crossing the scanning area are determined by triangulation based on the angles of rotation of the beams and the distance between the blocks; the obtained coordinates of the projectile are compared with the coordinates of the target in the image; if the coordinates match within a specified accuracy, a "hit" signal is generated, if they do not match, a "miss" signal is generated; the "hit" or "miss" signal is displayed on the interactive image as a visual effect.

2. The method according to paragraph 1, characterized in that the scanning area is bordered by a black stripe, against which the laser beams rest in the absence of a projectile.

3. The method according to paragraph 1, characterized in that the scanning blocks are placed on the bottom, side or top side of the scanning area.

4. The method according to paragraph 1, characterized in that the splitting of the laser beam is carried out using a diffractive optical structure or a multi-prism splitter.

5. The method according to paragraph 1, characterized in that the splitting of the laser beam is carried out using a fiber splitter and a set of collimators that form parallel beams.

6. The method according to paragraph 1, characterized in that the scanning frequency of each beam is from 100 to 1000 Hz.

7. The method according to paragraph 1, characterized in that a ball, puck, dart, paintball or airsoft bullet is used as the sports equipment.

8. A complex for interactively registering hits by a sports equipment according to paragraph 1, characterized in that it contains a device for displaying an interactive image, two laser scanning units, each unit including a continuous near-infrared laser, a laser beam splitter configured to form from 2 to 64 beams, a harmonic modulation generator, a controlled optical scanner, a receiving path with a narrow-band filter, a computer; the computer is configured to triangulate coordinates, compare with target coordinates, and generate a hit / miss signal.

9. The complex according to paragraph 8, characterized in that the laser beam splitter is made in the form of a diffractive optical structure or a multiprism or a fiber splitter with collimators.

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