GB2086243A

GB2086243A - Automatic Score Translator

Info

Publication number: GB2086243A
Application number: GB8039384A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-11-04
Filing date: 1980-12-09
Publication date: 1982-05-12

Abstract

An automatic score translator has a multiplicity of sensors which identify the location of a target board hit by a projectile. Sensors are arranged at the rear side of the target board and an electronic circuit receives the analogue sensor outputs and resolves them into a single signal which identifies the marginally largest sensor output. A projectile may contain a permanent magnet and the sensor system responds to field variations created by the arriving projectile. The score data selected is processed by an arithmetic circuit which may include a memory register, display encoders and a printout unit. Alternatively, a combination may be used of intensity and time lag differences in the propagation of an impact pulse created by the projectile on the board. Pressure sensitive elements are mounted on the rear of the target board and their outputs are fed to an electronic circuit which compares time lag and intensity levels of the impact pulse at different rear- board locations.

Description

SPECIFICATION Automatic Score Translator System in Projectile Games The present invention relates to a basic system for sensing and identifying the segment of an area upon which targeting shots with any kind of projectile are directed. To this category belong various games such as archery, crossbow, stone or dart throwing, as also training sites for sharp shooting. In these instances it is often difficult to arrange for observers to be near the target area, and assessment subsequent to the projectile impact is cumbersome, open to error or uncertainty, and wasteful of time. In some games there arises a danger to the assessor in that he may not have left the projectile throw orbit before the next round starts. In many games as dart throwing there exists an additional need to hold fast the results, usually by chalking them up on a blackboard.

Taking the dartboard as the primary example for explaining the invention principles it can be said that there are several reasons for trying to replace a human score assessor and writer of the score list. One of them is that it is a cumbersome task to chalk up and delete in quick succession the various score numbers of the participating players. Not always is the right person at hand for this task. The frequent deleting and re-writing of the numbers on a blackboard tends to be a messy job, the chalk settles on furniture, a carpets and, on the participants' lungs. These circumstances make the game less acceptable in elegant homes and pubs.

Proposals such as exist to 'automatize' the score listing are mainly bound up with a complete re-design of the dartboard itself. These attempts did not prove very successful because traditional boards are based on long manufacturing experience which cannot be disregarded.

This present proposal assumes from the beginning that traditional target boards should be usable; the required sensor mechanism for identifying the projectile location constitutes a separate entity which is attachable to the target board from the rear.

The effect which the throwing of a projectile can have on sensors arranged at the back of a target board depends on the nature of the forces sensed.

This proposal describes an example wherein the forces to be detected are magnetic, but the principles of the electric detection circuits by which the individual sections of the board hit by a projectile are identified may also be used in conjunction with other type of sensors, such as for example sensors detecting differences of propagation time of the impact pulse, or sensors for voltage gradients emanating from a projectile charged with static electricity. In all such cases a projectile landing on one sector of the board will inevitabiy affect also sensor sections belonging to neighbouring board sections. There will be differences in the intensity or time sequence of the sensed forces but these differences are likely to be small especially when a projectile lands close to a section border.

It is therefore one feature of the invention that it deals with the problem of safely selecting the largest sensor signal among several others generated at the same time. Or, as already referred to in an alternative form with selecting the first signal among others following at very short intervals.

Another feature of the invention is the design of a projectile suitable for throwing games (i.e.

dart) which is rendered suitable for magnetic detection techniques. Therewith connected are specific proposals for forming out a sensor suitable for being mounted to the back of a target board and for converting rapidly rising or falling magnetic fields into an electric signal.

Details of the invention will now be described with the aid of the enclosed drawings in which Figure 1 shows a dart according to the invention Figures 2 and 3 show portions of the rear sensor assembly Figure 4 shows the circuit for producing a unique output from the sensor with the largest signal while the remaining output terminals switch to or remain at zero logic level output.

Figure 5 shows a block diagram of the electronic system which uses the outputs from the Fig. 4 circuit and is programmed by means of a key board Figure 6 illustrates the impact propagation delays at the back of the target board Figure 7 and 8 modifications to target board/magnetic method Figure 9 and 10 modifications to target board/pulse sensor method.

Figure 1 shows an example of a magnetic dart.

n is the dart needle made of magnetizable steel: it thickens conically at the rear end n, to match the diameter of rod magnets m. Normally one rod bit m would suffice and the remaining bits may be made of brass or aluminium or plastics dependent on the weight requirement; on the other hand inserting two or three magnet bits in tandem would increase the magnetic field. Needle and magnets are inserted into a sleeve s made of suitable material. A recess r pressed or spun on after assembly holds the magnet piece(s) firmly pressed against the needle extension n. The stabilizing tailend t together with a plastic holder p may be inserted from the rear in the known manner. As a result of this arrangement the needle tip becomes magnetically polarized the field of which is noticable over a distance of 2-3 inches.

Figure 2 is an elevation of the sensor assembly as viewed from the rear surface of the dart board (looking in the direction towards the wall behind).

The circular bottom plate 1 carries perpendicularly thereto inserted or riveted-on inductor cores 3 made of iron. Around each such core is placed a bobbin and coil 4. These sensor coils are placed into section areas which are completely congruent with those of a standard dart board. These areas are defined by the magnetic shielding divisions 2. (See also a cross section, Figure 3). The ring areas a, b, and d have two serially connected sensor coils per sector.

Ring area c has only one coil per segment according to this example. The central ring area f and the center core g have one coil each.

Although also these areas have magnetic shield walls (2c) it may turn out that these are inadequate for differentiating these two central areas. In that case supporting means discussed further below may be employed. The entire sensor assembly has a flange 5 with holes 6 at predetermined positions. One may provide pins in the dart board which serve as location pins so that the assembly may quickly be fitted or refitted to any board with assurance of proper alignment of all the sections.

While the example here given is based on the sensing of magnetic field changes, similar or analogous arrangements may be designed for sensing electro-static fields or mechanical impact pulses already referred to. In all instances the main problem is of how to identify the sector with the largest signal (or with the first signal respectively) while completely ignoring all others having perhaps only marginally smaller (or delayed respectively) signals. This problem has been solved by adapting a technique already known for amplifying only the largest signal out of a multiplicity of signals. (See Jerald G. Graerne, "Designing with Operational Amplifiers" published by Burr-Brown, page 95).In our case, however, not the amplification of the largest signal is of interest but identifying the location of the source of the largest signal of positive polarity and the largest signal of negative polarity (if any) by clearcut logical level output signals. This is achieved by means of circuit Figure 4. On the left can be seen the 80 or 82 coils of the sensor assembly Fig. 2. Each coil is associated with two operational amplifiers A, and B. These circuits may with advantage be obtained from integrated packages such as Fairchild auA4136 which contains four such IC's in a single 14-pin dual in line package. Eighty coils can therefore be served by 40 packages which can readily be accommodated on two circuit cards together with associated discrete components.

In the example Figure 4 the voltage induced in the coil is applied to the non-inverting inputs of A and B. Where a positive e.m.f. is excited by the approaching dart magnetic field, amplifier A will produce a positive output signal amplified by the resistance ration R7 plus Fi8/R8. It will now be observed that all the amplifiers 'A' are connected together on the output side after diode d, by means of a common conducting rail mA. Assume that an unspecified number of the coils (1-80) produce simultaneously output voltages of similar shape along the time axis but of different amplitudes-such as is likely to occur when a dart is thrown at a dart board. The rail mA will be charged up to the highest amplified signal available from any of the 80 amplifiers.As this voltage is fed back to the inverting side of the inputs via voltage dividers R7, R8 only one amplifier can produce the desired positive output; namely that which has the largest coil signal. All the others will receive at the feedback input more positive voltage than is needed for the amplification limitation given by the said resistance ratio, that is to say the limitation would be heftier than required and thus swing the amplifier output into the negative range. It is thus possible to connect an output terminal called 'Set Score Number' to each diode d2 well knowing that only the highest positive voltage swing associated with a particular coil will drive this output to logic 1 whereas all the others remain at logic zero.

Now, the magnetic field of the dart can also generate a negative voltage excursion in any of the coils; this happens when the magnetic field is receding, that is to say when the dart does not stick well in the board but drops out and falls to the ground. In this instance, of course, the score selected must be cancelled again. A negative input voltage at amplifier 'A' will be fed back via diode d3 and thereby reinforce the negative voltage applied to input resistor R2 of the amplifier 'B'. The same is connected in a voltage follower configuration via diode d4. The output signal, if it is negative, will be passed on via diode d5 to the gate of transistorTR1 which becomes conductive so that the voltage drop across resistor R9 produces a logic high at the terminal 'Reset Score Number'.Again, all the amplifiers 'B' are connected together, via conductive rail m6, and thus only the largest negative signal is capable of producing the said logic output.

Means have to be provided to prevent the natural oscillation of a coil which after a positive swing may well dip into the negative range, from causing a faulty 'reset' output. To this end the resistor R3 is provided which when capacitor Cl charges positive after the first positive swing, acts like a summing resistor thereby counteracting any subsequent negative swing applied to R1. The R C constant of the capacitor C1 and the resistor R4 would be so dimensioned that the sum of the positive and negative input currents to amplifier 'B' is approximately zero, or preferably remains a little positive. This would exclude amplifier 'B' from being affected by the decaying oscillations in the coils after a dart arrival.

Figure 5 shows how the 'SET' and 'RESET' outputs from the sensor board are used. Each 'SET' output encodes a definite score number in the unit '(C)' which is then latched and causes a subtraction from the instant total in the arithmetic unit '(E)'; and each RESET output encodes the same score number in unit '(C)' but causes it to be added to the instant total in the arithmetic unit '(E)'. Via the memory register '(F)' the arithmetic unit may also control the displays X and Z on the display board '(G)'; therefore, a RESET output would for example also cancel the display of the score number in column X, and enter the preceding total under column Z.

The memory register '(F)' also receives inputs from the keyboard '(H)' which has the following keys: Two rows of participants letters A to H: two team keys (I and II) to signify to which team a player belongs, and a dial board Hs which enables start totals for each side to be selected and displayed at SC.T. If only two persons play, then it is sufficient to key in I and II, dependent who starts first. In a simplified form, no keyboard at all would be necessary when the convention is implemented that the score is entered on the left side for whomsoever starts first followed by a display on the right for the score of the partner, even irrespective of the numbers of players in the team. The arrangement according to Figure 5 is optional where it is believed to be of value of highlight also individual performance not merely team performance.With this equipment it is not essential that players keep to a definite sequential order. For example the first player may be one in team II having allotted to him the letter C.

Accordingly the combination C-ll would be selected on the keyboard whereby the score encoder and the arithmetic unit are put into a state of readiness to receive instructions from the sensor assembly via circuit Figure 4. After the first dart the number scored appears in line Il-C under column X. Simultaneously the difference between the start total and the present score is displayed under column Z on line Il-C. The memory unit stores the result. The next player may be I-B, and the third player be ll-A. To begin with the reduced start total is shifted into the Il-A line under column Z while the score of the previous player 11- C extinguishes (though kept in memory). The scores obtained by the third player are now displayed under column X. And so on.What concerns the display of the score, there is also a usage which prescribes that the score should be displayed only after the third throw. This can of course be implemented by logic incorporated in the arithmetic unit which automatically adds up three consecutive score numbers and thereafter blocks any further numbers until a push button mounted near the dart board is actuated whereafter the score display appears. This may then remain until the next player of the same team has thrown his/her darts and then causes the score to be displayed in the manner just indicated. The scores achieved by each individual player may be further processed by producing aggregates, for performance comparison.

However, scores below a certain remnant totals figure are not counted, and this again would be executed automatically through incorporation in the system program.-The play is thus divided in a first portion called the 'scoring play' which lasts until for each team the preset lower remnant total is reached, and the 'finishing play' wherein players do no longer concentrate on obtaining the highest scores but rather on planned precise scoring so that in the course of three throws the remnant total is reduced to zero. The performance quality of players is then reflected on the one hand in the average scores obtained in the first part of the game. To hold all the data in the memory bank '(F)' and finally to process them for the obtaining of the evaluation figures just mentioned, will be part of the instruction imparted on the Figure 5 data processing system.

When the display board is full, that is to say when each of the players of a team have had their turn of three darts, the key 'C' is depressed whereby the residual totals are carried forward and the SC.T. displays are changed accordingly.

When during the finishing part of the game a score is obtained which would cause the residual total to go negative, the electronic circuit would be arranged to cancel this result and recall the preceding residual total and display it again-in other words to render the last score fully ineffective.

A more developed automatic score translator may also comprise a programming key board enabling players to modify the game rules in accordance with various versions of the game.

It has earlier been mentioned that the selection of the 'bull' center and surrounding ring respectively might turn out to pose difficulties. If that occurs it is suggested that the center portions of the board may be made of an insert core and ring, its material being impregnated in its middle areas by iron dust particles. This would introduce a sharper definition of the narrow areas in relation to the pickup coils thereunder and thus restore the sensitivity to the required minimum difference signal levels. This principle could be applied to all the narrow segments as well.

In outdoor target boards the individual segments are likely to be larger and therefore it might be possible to employ the impact pulses passing through the board as the criterium for location detection.

The principle is explained by means of Figure 6.

When the projectile hits the target board 'B' at the point CO the impact pulse is propagated and radiated in all directions within the board; but is clear that the most direct path to the back of the board is the one which emerges at C,. Other pulse fronts will reach the rear surface, for example at point C2 marginally later. The path difference length is 'a' and the time difference is a divided by the propagation velocity in the material concerned. An electronic circuit would be needed which can identify the segment into which point C1 falls and suppresses the outputs from all the other segments. It is here suggested that piezoceramic or similar pressure sensitive transducers are attached to the rear surface of the target board. The electric output from these transducers may then be applied to the operational amplifier circuit of Figure 4.This circuit, with very few modifications, can readily be adapted for detecting and locating the first-most signal arriving at the back of the board and for generating a corresponding logical output available for score evaluation in a system such as exemplified in Figure 5.

Because of the relatively small dimensions of the dart board segments the technique just outlined may not be applicable to dartboards and the magnetic detection system appears preferable. When the margin of detection becomes too small differences inthe elasticity coefficient of the board material in different propagation directions may already upset the result. In the larger outdoor boards such differences would not influence the score result.

Finally it should be mentioned that the proposed Score Translator system may also be connectable to a printout device for delivering a written record of the average and finishing scores for teams and individual players where applicable.

Supplementary Notes While the circuit Figure 4 ought to provide adequate sector identification if the noise background is low, it would nevertheless be desirable to increase the input difference signals.

To this end the effect of the magnetic field of the projectile in the wanted sector can be increased by making this sector (except a fringe margin around its periphery), magnetically conductive.

Ideally the full board depth should be made magnetically permeable. A simplified method is shown in Figures 7 and 8. The board consists of two plates, 1 2a and 1 2b, which are bonded together. The target board 1 2a has recesses 8, 9, 10, 11 (Figure 8 is a cross section, Figure 9 is view A-A) which exemplify the geometry to be applied to all the sectors of the Board; into these recesses a ferrite semi-hard rubber or the like substance is placed. It should have good magnetic susceptibility. The reinforcement board 1 2b has holes allowing the prolonged cores 3 of the coils 4 to protrude and to touch the magnetic rubber fillings. The coil system is firmly riveted to a base iron plate which serves as a magnetic sink and can be fixed to the board 1 2b via distance sleeves.

The electronic discrimination circuit would with advantage be fixed on the rear of base plate 1 to make connection links as short as possible.

As far as the described impact sensor method is concerned the same requires an electronic discriminator circuit similar to that shown in Figure 4; the difference being that the capacitor C1 is not connected to diode d2 but with diode dt.

Also, no negative input voltages need be compared because the dropping back of a dart or projectile will obviously not produce any signal at all. To detect at least those darts or projectiles which hit the metal dividing line between target sectors, it is proposed to fix a pressure transducer to the metal. This transducer will not be affected by minor pulses but when there is a direct hit on the wire it will produce an output signal above an adjustabie threshold and generate the 'Reset Score' logic output required to cancel the preceding score released by the impact itself. In this way, rebouncing projectiles will not produce a score.

To improve pulse discrimination on the basis of Figure 6, it is proposed to produce on the rear side of the target board 12 (Fig. 9 and 1 0) a pattern of narrow deep grooves. The pattern is identical with the target sector boundary pattern. (Note grooves 20 and mechanical pulse transducers 22). These slots may be filled with a substance having a lower specific weight than that of the board material.

A still further improvement of the wanted signal compared with the unwanted signal may be obtained by iron inserts 21 pushed into the bottom of the grooves (see example groove 20a).

If a projectile tip n hits the board adjacent to the boundary wire 7 a portion of the impact pulse 24 is reflected by the heavier iron insert rails 21 and is again reflected from the top surface of the board, and reflected again therefrom in an inverted form causing a depression wave to travel towards the neighbouring sector. Here it will mix with other pulse lines and diminish the pulse sensed by the transducer there. On the other hand, the wanted pulse on the left of the sector dividing wire will travel along line 23, and will thus not merely arrive earlier than on any neighbouring sector sensor but also with greater strength. This will enable the modified Fig. 4 identifying circuit to produce the wanted unique output more safely.

The pressure transducer component 22 may optionally be a silicon-based integrated circuit incorporating electronic piezo element and coupled amplifiers.

Claims

1. An Automatic Score Translator System in Projectile Games signified by means which detect the dynamic and transitional effect exerted by the throw of a dart into a particular sector of the dart board.

2. An Automatic Score Translator System in Projectile Games as in claim 1 wherein the detection means are mounted on or close to the rear of the dartboard or are inserted into the board.

3. An Automatic Score Translator System in Projectile Games as in claims 1 and 2 wherein the propagation of the dynamic effects from the impact area to the corresponding detector is increased in directionality and decreased in dispersiveness by the incorporation of materials into the dart board construction which differ from the basic dart board material, partly such material regions as would conduct the dynamic effect on a dart board sector preferentially to the corresponding sector detector; partly other material regions, including the sector dividers (2, Fig. 2) which shield a neighbouring sector from receiving a substantial part of the dynamic effect.

4. An Automatic Score Translator System in Projectile Games as in claims 1-3 wherein the said dynamic effect derives from a magnetic field emanating from the dart in flight.

5. Automatic Score Translator System for Projectile Games as in claim 4 wherein the darts are made of hollow shafts (S) into which an essentially cylindrical permanent magnet (m) is placed, and which imparts on the steel dart pin (n) a longitudinal polarisation (Fig. 1).

6. Automatic Score Translator System in Projectile Games wherein the detector is a magnetic field sensor of the static or reactive (inductor) type (3, 4, Fig. 2, 3).

7. Automatic Score Translator System for Projectile Games wherein the detector is a mechanical impulse or vibration detector (22, Fig.

9, 1 O).

8. An automatic score translator system in Projectile Games as in claim 7 wherein the vibration detector includes a piezo-electric sensor.

9. Automatic score translator systems for Projectile Games as in claims, 1, 6 and 7 wherein the rear of the dart board opposite the area of each target sector is hollowed out to depth of at least one quarter (8, 9, 10, 11, Figs 7, 8) of the thickness of the board and the cavities are filied with magnetically conductive material to increase the field strength interacting with the magnetic field sensors (3, 4).

1 0. Automatic score translator systems for Projectile Games wherein there is provided an electrical impulse selector circuit which receives input signals from various sector sensors simultaneously or consecutively and which consists of two pairs of operational amplifiers (A, B) for each sector sensor pairs wherein the first row responds only to positive sensor output signals produced by an approaching dart and the second row responds only to negative sensor output signals produced by a dart which falls out.

11. Automatic score translator etc. as in claim 10 wherein all the operational amplifier outputs in the first row (A, Fig. 4) are related to each other in such a manner that only that with the marginally largest positive input produces an amplified output pulse whereas all the other amplifiers are disabled and produce no output, and wherein the signal produced by the thus selected operational amplifier is applied to a score encoder (Fig. 5) for encoding the score associated with the sector from which the largest sensor output derives.

1 2. Automatic score translator etc. as in claim 10 wherein all the operational amplifier outputs in the second row (B, Fig. 4) are related to each other in such a manner that only that with the marginally largest negative input produces an amplified output pulse whereas all the other amplifiers are disabled and produce no output, and wherein the signal produced by the thus selected op. amp is applied to a score encoder (Fig. 5) for cancelling the score associated with the sector from which the largest sensor output derives.

1 3. Automatic Score Translator System in Projectile Games which comprises a score display panel for a total score and for the intermediate score status of more than one pair of players, and a keyboard (H) for setting the initial total score in accordance with the conventional rules of the game.

14. Automatic Score Translator System in Projectile Games as in claim 1 3 in which system a further keyboard (A-H) is provided for selecting a particular player out of a number of quasisimultaneously playing pairs (A to H) and where the instant score status for any one playing pair is memorized in a memory register (F) which can be called up for the selective display by using the said keyboard (A-H) and which display (G) would subsequently be altered by the player pair in action according to the scores obtained by it with the aid of the automatic score identifier circuit (as shown in the example of Fig. 4), the new score total being overwritten into the said memory register sector of the player pair in the register (F), to be ready for renewed call-up when the turn again falls to that player pair to throw their darts.

1 5. Automatic Score Translator System in Projectile Games as in claims 13 and 14 wherein the display board (G) has two columns (x, z) for each player in order to present a display for the present instant throw score (for example in column x) as well as the immediately preceding instant total score (for example in column z); or, to display the most recent total instant score side by side with the immediately preceding instant total score to give the viewer a clear picture of the players performance.