IL101016A - Dynamically activated optical instrument for producing control signals - Google Patents

Description

REF : 2068/92 DYNAMICALLY ACTIVATED OPTICAL INSTRUMENT FOR PRODUCING CONTROL SIGNALS 2068/92 ηΥΝΓΑ ΤΓ.ΑΤ J,Y ACTIVATED OPTICAL INSTRUMENT FOR PRODUCING CONTROL SIGNALS Field of the Invention This invention relates to dynamically activated optical instruments for producing control signals. More particularly, it relates to an optical instrument which is activated by dynamic stimuli, generally by motions of an operator's body, and produces signals which control a musical instrument, a computer-operated visual game, or other devices.

Backgreund of the Invention Apparatus for producing sounds by radiation have been known in the art for a long time. They are based on the principle of producing radiation, modifying it, sensing the modifications and translating the same to signals, e.g. electric or electronic signals, which in turn produce musical tones. The modifications of the radiation may be produced by the motion of the operator's body in a space that is traversed by the radiation. The operator will be referred to hereinafter as "the player".

French Patent 72.39367 utilizes radar radiation. The player's body reflects the radiation towards a sensor and the Doppler effect is produced, which generates signals that are translated into acoustic frequencies. The music may be generated as a function of the speed of 2068 92 the player's motion or of his distance from the radiation source.

French Patent 81.06219 uses laser radiation, which surrounds a space in which the player moves and the tones are produced by the interception of a ray by the player's body.

U.S. P. 4,429,607 describes an apparatus comprising a number of light emitters and sensors adjacent thereto, tones being produced by reflecting back, e.g. by means of a finger, an emitted ray to the corresponding sensor.

WO 87/02168 describes, among other things, an apparatus applying the same tone-producing means as the aforesaid U.S. patent, but using retroflective elements applied to the human body to produce reflection that is stronger than random reflection, due e.g. to the ceiling. Alternatively, random reflections are neutralized by confining both the emitted and the reflected beams within a narrow tube. The application also describes a way of producing different octaves by sensing the order in which a plurality of laser rays are intercepted by the player's body.

European Patent Application No. 342037 describes an instrument for producing tone signals, which generate sounds, such as musical notes, or optical images and the like, comprising radiation emitters arranged to emit radiation each into an elongated emission space, sensors 2068 92 associated each with an emitter and sensitive to radiation received from an elongated sensing space which is non-coincident with the emission space of the respective emitter, the associated emission and sensing spaces partially overlapping as the result of different orientations thereof, and control signals being generated in response to the sensors receiving radiation reflected from a point of said overlap. Such an instrument, while being highly efficient and operationally satisfactory, is somewhat complex and expensive to make and requires adjustments depending on the characteristics of the space in which it operates.

Purpose of the Invention It is a purpose of this invention to provide an optical apparatus which is adapted to produce, in response to dynamic stimuli, control signals for generating sounds or musical notes, or optical images or the like, or operating safety devices or interfaces, which is free from all the defects of the prior art apparatus.

It is another object of the invention to provide such an apparatus, which operates efficiently in any surroundings and is not affected by the shape and dimensions of the room in which it is placed or by objects that may be present in it.

It is a further object of the invention to provide such an apparatus which adjusts itself to different surroundings. 2068/92 It is a still further purpose of the invention to provide such an apparatus which requires only one source of radiation.

It is a still further purpose of the invention to provide such an apparatus which operates by means of any desired kind of radiation.

It is a still further purpose of the invention to provide such an apparatus which adjusts its sensitivity to radiation, so as to provide constantly the desired response to the dynamic stimuli by which it is activated.

It is a still further purpose of the invention to provide such an apparatus that is extremely simple as to structure and economical to make and to operate.

It is a still further object of the invention to provide a method for producing control signals by producing radiation in an operating environment, and producing control signals in predetermined response to activating, dynamic stimuli, independently of the characteristics of the operating environment.

Other purposes of the invention will appear as the description proceeds. 2068/92 Summarv of the Invention The apparatus according to the invention is characterized in that it comprises, in combination with a radiation source, at least one radiation sensor, means for activating a controlled device in response to radiation detected by said sensor, and means for regulating the sensitivity, or reactivity, of said activating means in such a way that they will not activate said controlled device in response to radiation received by the sensor in the absence of dynamic stimuli, but will activate the same whenever such stimuli are present.

By "dynamic stimuli" are meant those changes in the radiation received by the sensors that are produced by a person using the apparatus for the purpose of rendering the controlled device operative to produce the effect that is proper to it, such as musical tones in the case of a musical instrument, game actions in the case of visual games, the sending of appropriate commands in the case of an interface, and the like.

The source of radiation may be constituted by at least one emitter that is part of the apparatus - that will be referred to as "internal (radiation) sources" - or by means that are not a part of the apparatus but provide radiation in the space, in which the apparatus is intended to operate -that will be referred to as "external (radiation) sources". Typically, an external source may be constituted by the lighting of the room in which 2068/92 the apparatus is intended to operate.

Preferably, the apparatus comprises a number of units or "segments" (as they will sometimes be called hereinafter) and each unit or segment comprises at least one sensor, and, if the source of radiation is internal, at least one emitter.

In a preferred form of the invention, the sensitivity regulating means comprise means for determining two received-radiation thresholds, an upper one above which the activating means activate the controlled device and a lower one below which they de-activate the same, the gap between said two levels, wherein the activating means remain inoperative, corresponding to a level of noise.

In a further preferred form of the invention, the sensor produces output signals in response to radiation received and means are provided for sampling said signals, counting only the signals that are produced, within a certain time period, by radiation having an intensity above a predetermined minimum, and generating control signals in response to the number of the counted signals.

In a particular form of the invention, the activating and sensitivity regulating means comprise processor means for activating emitter means to emit radiation pulses, sampling the sensor output signals in 2068 92 predetermined timed relation to the emitted pulses, deriving from the sampled sensor output signals a sensing parameter, comparing the value of said sensing parameter with reference values thereof, and generating control, activating and deactivating, signals and transmitting the same to the controlled device depending on the result of said comparison.

The word "radiation", as used herein, includes any kind of radiation, such as infrared, ultrasonic, visible light or laser radiation or microwaves or other kinds of electromagnetic waves and in general any radiation that may be emitted and received by means known in the art.

The expression "control signals", as used herein, includes any electric or electronic signals or any signals that may be produced by the activating means in response to sensor output signals due to radiation received by the sensor. The said control signals, as already stated, are used to control other devices, most commonly musical instruments or computer controlled visual games, or other computers or interfaces and in general any computer-controlled or electrically- or electronically-controlled devices, generally designated herein as "controlled devices". Since a typical - though not the only - use of the instrument according to the invention is to control musical instruments or visual games, the person using the apparatus and producing or controlling the dynamic stimuli which activate it, will be called hereinafter "the player". 2068/92 he expression "control signals", as used herein, includes any electric or electronic signals or any signals that may be produced by the activating means in response to sensor output signals due to radiation received by the sensor. The said control signals, as already stated, are used to control other devices, most commonly musical instruments or computer controlled visual games, or other computers or interfaces and in general any computer-controlled or electrically- or electronically-controlled devices, generally designated herein as "controlled devices". Since a typical - though not the only - use of the instrument according to the invention is to control musical instruments or visual games, the person using the apparatus and producing or controlling the dynamic stimuli which activate it, will be called hereinafter "the player".

The invention also comprises a method for producing control signals in response to dynamic stimuli, which comprises creating radiation in a space, sensing a physically, generally quantitatively, definable characteristic of the radiation received at one or more points in said space, determining in a zeroing operation the value of a sensing parameter, having a predetermined correlation to said characteristic, in the absence of dynamic stimuli - hereinafter called the " reference threshold value" of said parameter - and thereafter, in the normal operation of the apparatus, repeatedly determining the value of the same sensing parameter and producing a control signal whenever a predetermined deviation from said reference threshold value is detected. Said radiation characteristic will generally be defined in terms of intensity, but may be defined otherwise, e.g. in terms of frequency etc.; 2068/92 and it may not, and generally will not, be quantitatively determined since it is represented, in carrying out the invention, by the sensing parameter. The sensing parameter may be defined e.g. as a number of pulses in a given time interval, or may be defined in terms of different variables, such as a time elapsed between emission and reception of radiation, a frequency, and so forth. The correlation between said sensing parameter and said characteristic may be an identity, viz. the parameter may be a measure of the characteristic, or parameter and characteristic may be different even in nature and any convenient correlation between them may be established, as will be better understood hereinafter. The correlation may be wholly empirical and it may vary in different operating environments and/or circumstances, as will be better understood hereinafter.

Preferably a different control signal is associated with each sensor and therefore with each point at which the received radiation is sensed. For instance, the output signal associated with each sensor may be used to produce a given musical tone - by which term is meant any sound having musical significance and in general a definite pitch, which, in the customary scales, such as the chromatic scale, is physically definable in terms of basic frequency and octave - or it may produce an instruction to a computer to carry out a given operation, such as the production of an image or its modification or displacement, or any other predetermined action of any device controlled by the instrument according to the invention. 2068/92 referably a different control signal is associated with each sensor and therefore with each point at which the received radiation is sensed. For instance, the output signal associated with each sensor may be used to produce a given musical tone - by which term is meant any sound having musical significance and in general a definite pitch, which, in the customary scales, such as the chromatic scale, is physically definable in terms of basic frequency and octave - or it may produce an instruction to a computer to carry out a given operation, such as the production of an image or its modification or displacement, or any other predetermined action of any device controlled by the instrument according to the invention.

Description of the Drawings Fig. 1 schematically illustrates a polygon made from 8 units, according to a preferred embodiment of the invention; - Fig. 2 schematically illustrates the emitters and sensors of a unit according to one embodiment of the invention; - Fig. 3 is a diagram illustrating the operation of a device according to an embodiment of the invention; - Fig. 4 is a block diagram schematically illustrating the relations between the units, the central processor and the interface to the game or instrument, and the flow and processing of information; and - Figs 5 and 6 are electronic diagrams of component parts of a specific embodiment of the invention, and more precisely of a control circuit and a panel circuit respectively.

Detailed Description of Preferred T¾nho impnte In the preferred embodiment illustrated in Figs. 1 and 2, the apparatus according to the invention comprises a number of units from 1 upwards - 8 in the specific example illustrated, but this number has no particular significance and may be changed at will - each of which has the form of a segment 10, so that the succession of those segments in mutual abutment constitutes a polygon, the player generally standing inside the polygon itself. Each segment 10 comprises a bottom portion of base 11 and a top portion or cover 12, connected to the base in any suitable way. In Fig. 2a the cover 12 is shown as removed from the base 11 and turned upside down, to show its inner surface. Base 11 carries an emitter assembly generally indicated at 31 (though this latter may be omitted, as will be explained hereinafter) and a sensor assembly generally indicated at 15. The top cover 12 is provided with windows 24, over the emitter assembly, and 26, over the sensor assembly. The emitter assembly comprises an emitter 13, which may be e.g. a LED (Light Emitting Diode) or any other kind of emitter, and preferably, but not necessarily, means for directing the emitted radiation beam in a predetermined direction. In the embodiment described, the direction of the beam is 2068/92 essentially vertical and is obtained by concentrating the radiation emitted by the LED by means of a cylindrical lens 20 and directing it onto a mirror 22, slanted at about 45° to the vertical, from which the beam is reflected generally upwards. These elements are shown in perspective in Fig. 2b. The reflected radiation passes through window 24 and forms an upwardly directed beam. Said beam, of course, is outwardly flared from its vertex, viz. from the level of the emitter, upwards and has the general shape of a pyramid having a generally quadrilateral cross-section or base. The geometry of its base depends on the lens 20, which, being cylindrical, tends to produce a beam that is elongated parallel to the direction of the lens axis. The specific intensity of the radiation, viz. the amount of radiation which passes through a unit surface of a horizontal cross-section of the beam, decreases from the vertex of the emission space upwards.

The sensing assembly 15 comprises a mirror 25, slanting at about 45° to the vertical, on which radiation reflected by the ceiling of the room in which the apparatus is placed, or by any other reflecting body which crosses the emission space, impinges after having passed through opening 26 of cover 12, alined with said mirror. Mirror 25 reflects the radiation to lens 27, these elements being shown in perspective in Fig. 2d. From lens 27 the radiation reaches cylindrical lens 32, shown in perspective in Fig. 2c. From cylindrical lens 32, the radiation reaches a sensor, e.g. a photoelectric cell 14, which produces an electric signal in response to the radiation received. The geometry of the sensing assembly determines a different sensing beam for each unit 10, so that the units 20 will not interfere with each other - viz. the optical components described and the openings in the cover 12 are so dimensioned and positioned that only the radiation from a certain space - "sensing beam" - reaches each sensor, and the radiation which reaches any given sensor does not reach any of the others. It will be understood that the optical components hereinbefore described and their disposition are not critical and any skilled person can select components that are different in whole or in part and arrange them in a totally or partially different way in order to obtain the desired emission and sensing beams. As already noted, it is not necessary that each segment 10 should comprise an emitter assembly and the apparatus according to the invention may comprise, instead, one or more separate emitters, each if which emits radiation that will be received by more than one sensor, in which case there will not be associated with each segment an emitter assembly and an emitter beam.

The operation of a single element of the apparatus, viz. an emitter and a sensor, which, in the embodiment described, are associated with a given segment 10, will now be described. It will be understood that the same operations will take place for all other elements, though preferably not at the same time, in order to avoid interference between different elements - in other words, a central processor or computer such as that schematically indicated in Fig. 4 - which figure is self-explanatory - e.g., a microprocessor, will activate the several elements of the apparatus at successive time intervals, which however are so short as to give the effect of a continuous operation of the apparatus. It will also be 2068/92 understood that, as already stated, an emitter may cooperate with different sensors, and thus may be considered as a part of a plurality of elements of the apparatus. In the embodiment illustrated, the radiation is emitted by pulses. The frequency of the pulses may be controlled by the central processor, and let us assume, by way of example, that it is 2000 pulses per second. The sensor of the element under consideration generates an output signal in response to a pulse received, which is also a pulse, the length or duration of which increases with increasing intensity of the radiation received. To distinguish it from the pulses sent by the emitter, it will be called "sensor pulse" or "sensor signal". When the processor activates the element, it triggers the emission of the pulses by the emitter. After a certain time, the processor samples the output of the sensor. The time elapsed between the triggering of the emission and the sampling of the sensor output, will be called "sample delay time" and indicated by SDT. The SDT can be changed by the computer. It influences the operation of the apparatus and therefore it is desirably set at an optimal value, the determination of which will be explained hereinafter.

When the computer samples the sensor output, it senses and registers at each sampling whether a sensor signal is still being sent. If the sensor has not received an emitter pulse, and therefore has not responded by sending a sensor signal, or if it has received a weak emitter pulse and has therefore sent a sensor signal that has lasted less than the time SDT, the computer will register the absence of such a signal (zero). If the sensor has received an emitter pulse strong enough 2068/92 to cause it to emit a sensor signal the duration of which exceeds SDT, the computer will register the existence of said signal (one). The computer will count the number of sensor pulses (ones) it detects during a given length of time or "measuring cycle". The maximum number of sensor pulses that could be detected during a measuring cycle, is obviously equal to the number of emitter pulses that have been sent during said cycle, which depends on the duration of the cycle and on the frequency of the emitter pulses. In this example, it is assumed that said maximum number of sensor pulses is 64, corresponding to a duration of each measuring cycle of about 1/30 second (more exactly 64/2000). It is seen that the number of sensor pulses detected in each measuring cycle, which will be called "intensity number" and will be indicated by IN (and is comprised in the case described between zero and 64) provides a measure of the intensity of the radiation received by the sensor and is, in this embodiment, the sensing parameter. However the radiation intensity and the number IN of sensor pulses detected are not proportional, since the latter number is influenced by other factors, and mainly by the value of SDT, as it is clear that if SDT increases, more sensor pulses will go undetected, all other things being equal.

The operation by which the apparatus is prepared for operation in a given environment, which will be called the "zeroing operation", will now be described with reference to a single sensor. During the zeroing operation, none of the dynamic stimuli that will be applied to the apparatus and to which the apparatus will react in normal operation, are present. The apparatus is started and the emitters begin to emit IR 2068/92 (or other radiation) pulses controlled by the computer. The sensor will output sensor pulses and the computer will sample them and compute the IN value by counting the pulses- all as explained hereinbefore - and will register said value in its memory, all within a few thousands of a second (e.g., 30 milliseconds). Since no dynamic stimuli are present during the zeroing operation, said value may be called "idle mode intensity number" and indicated by IDN. IDN is the reference threshold value of the sensing parameter IN. Due to the internal and external electronic and optical noise, this number is not stable and varies from measuring cycle to measuring cycle. Its maximum variation will be called "noise number" and indicated by NN. It is determined empirically by operating the apparatus in the environment in which it is intended to operate normally, which is the same in which the zeroing operation is carried out, and under normal conditions, e.g. normal room temperature, and measuring IDN repeatedly over a sufficient length of time, e.g. one hour. Alternatively NN could be calculated by summing all the contributions of the various components - e.g. sensor noise, amplifier noise, digital noise, external induction noise, optical noise from external radiation sources, and so on - each of which is individually known or easily determined by persons skilled in the art.

According to an elementary embodiment of the invention, the apparatus could be programmed in such a way as to actuate the controlled device -be it a terminal device or an interface to a terminal device - to perform its operations when the apparatus is subject to a radiation the intensity of which corresponds to a sensing parameter IN equal to or less than the 2068/92 reference threshold value IDN, viz. which is not higher than the radiation it would receive in the absence of dynamic stimuli (as this expression has been defined hereinbefore). Thus the controlled device would be activated when at least one sensor receives a radiation more intense than that expressed by IDN and de-activated when all sensors receive a radiation equal to or lower than that expressed by IDN. However, the presence of noise might cause the controlled device to be activated in the absence of dynamic stimuli, and to avoid this, the activation threshold should be increased by NN.

It is desirable to control the sensitivity of the apparatus, viz. the intensity of the dynamic stimulus that is required in order that the actuated device will respond. For this purpose, both activation or lower and deactivation or higher thresholds are increased by a factor that will be called the "sensitivity number" and will be indicated by SN. In this way the apparatus will only respond to dynamic stimuli that are not too small and the minimum intensity of which increases with increasing SN. The lower and higher thresholds, indicated respectively as OFFIN and ONIN, will be expressed by: OFFIN = IDN + SN ONIN = IDN + SN + NN SN is determined empirically by operating the apparatus under normal conditions and varying it until the apparatus responds satisfactorily to a given dynamic stimulus: e.g., the action of a typical object, such as the hand of the player or an optically equivalent object, at a typical height, say e.g. 1.2 meters, at the center of the area in which the player normally operates. The value of SN, and well as that of NN, are registered in the computer's memory as known parameters, as part of the zeroing operation.

It will be clear from the above description that the first parameter to be determined, or more correctly, to which an optimum value must be attributed, in the zeroing operation, is SDT. The sensors have a typical delay time between the time they receive the optical pulse and the time they generate the electronic response. As mentioned earlier, the length of the response signal is proportional to the intensity of the optical signal received. In order to optimize SDT, its value is set at first as close after said delay time as possible, in order to achieve maximum sensitivity: this value will be called "initial SDT" - ISDT. A weak optical signal will cause the sensor to generate a short electronic pulse, but still it will be identified by the processor because it samples the output of the sensor right after the pulse started. The processor will measures the IDN using ISDT. If the resulting number is too high in order for OFFIN and ONIN to be in their designated range because of very strong optical signal (IDN > 64-CNN+SN) ) the processor will lower the sensitivity by incrementing the SDT by one microsecond, and check the IDN again.

By incrementing SDT by 1 microsecond, the processor samples the output of the sensor 1 microsecond+ ISDT after their response. Only emitted optical signals which cause pulses 1 microsecond+ ISDT to be generated by the sensor, will be identified by the processor. These pulses have to be stronger in their intensity. The processor will repeat this procedure until the sensitivity decreases so that IDN reaches a satisfactory value, which should be in the range: 0 < IDN < (64 - (NN + SN) ). The SDT which produces said result will be registered in the processor's memory and maintained in the normal operation of the apparatus, at least unless and until a change of environment makes a new zeroing operation necessary. It may be called "working SDT" and indicated by WSDT.

These operations are illustrated in the diagram of Fig. 3, wherein the abscissae are times and the ordinates numbers of sensor pulses counted in a measuring cycle. At the beginning of the zeroing operation, indicated by segment 40, SDT is very small and as a result IN is too high (64 as shown in the diagram). SDT is then increased by 1 microsecond (segment 41) whereby IN decreases to 60, which is still too high. SDT is repeatedly increased producing the successive segments shown, and IN decreases, until an IN of 40 is reached (segment 42). This is a satisfactory value, for, with the values of SN and NN which have been previously established, ONIN is 60, comprised in the 0-64 interval. The SDT which has produced said value of IN - which is taken as IDN=40, based on which ONIN and OFFIN are calculated - will be used throughout the operation of the apparatus and becomes therefore WSDT. Slanted lines 43 and 44 illustrate how the apparatus will work in normal operation. If a dynamic stimulus is present, IN will rise from IDN to 60, which is ONIN, and the controlled device will be activated. If the dynamic stimulus ceases, IN will decrease from 60 to OFFIN, at which point the controlled device will be de-activated.

The two thresholds OFFIN and ONIN are actually numbers of pulses counted in a measuring cycle, viz. their dimension is sec'l . Of course, NN and SN are expressed in the same units. If the number of pulses emitted by the emitter is 64 per measuring cycle, as has been assumed herein by way of example, both OFFIN and ONIN must be comprised between zero and 64. Increasing the number of emitted pulses increases the accuracy of the apparatus but also its response time, while decreasing said number decreases both accuracy and response time. Since high accuracy and low response time are desirable, a compromise must be reached, and in most practical cases setting the number of pulses at 64 per measuring cycle achieves a good compromise.

During normal operation, the computer checks the IN every 30 to 40 milliseconds. If the IN value rises above ONIN, the computer operates an "on" signal, viz. activates the controlled device (e..g. video/computer game, electronic musical device or interface). If the IN value is between OFFIN and ONIN, no change is effected and the controlled device 2068/92 continues to operate or not to operate, as the case may be. If the IN value decreases below OFFIN, the computer generates an "off' signal, viz. deactivates the controlled device. The gap between the two thresholds prevents noise from sending such "on" and "off signals at inappropriate values of IN.

When more than one sensor is employed, each sensor will be assigned its own specific SDT, OFFIN and ONIN values, and the computer will compare the IN of each sensor with its specific parameters, and will produce "on" and "off' signals accordingly.

In this embodiment of the invention: the intensity of the radiation received by a sensor is is the quantitatively definable characteristic of the radiation received; the number of sensor pulses counted by the processor in a measuring cycles is the sensing parameter; the correlation between said parameter and said characteristic is the relationship between each intensity of radiation and the corresponding number of sensor pulses, which relationship depends on the apparatus characteristics and on the particular SDT chosen; the reference threshold value of said sensing parameter is the number of pulses IN measured in the environment in which the apparatus is intended to operate and in the absence of dynamic stimuli; 2068/92 the deviation from said reference threshold value which causes the production of a control ("on" or "off') signal is a predetermined deviation of said sensing parameter, in excess, from said threshold value -preferably a deviation in excess equal to the sum of the noise number and the sensitivity number, as hereinbefore defined.

The zeroing operation has been described with reference to a single sensor. The computer will relate separately to each sensor in the apparatus, and if, e.g., there are 8 segments and 8 sensors in the apparatus, the computer will concurrently zero each one of them independently. Depending on the shape of the room, the objects contained therein and the position of the apparatus within it, the various parameters, including the measuring cycle, used or established in zeroing the apparatus, may be different from sensor to sensor and from unit 10 to unit 10.

When the instrument is used, a player is stationed in the playing area, which is in general the area within the polygon defined by the segments 10, and moves parts of his body in such a way as to produce dynamic stimuli, by creating changes in the radiation received by the various sensors. This occurs because in the absence of a player the radiation emitted by the emitters carried by the apparatus segments, or by the central emitter or emitters, is reflected by the ceiling of the room in which the apparatus is placed, but when a part of the body of a player penetrate an emission beam and reflects the radiation to a sensor, it is 2068/92 closer to the emitter than the ceiling; and it is obvious that the closer the reflecting surface is to the emitter, the more intense will the reflected radiation be. The computer will then receive from the sensor or sensors so affected, within the measuring cycle, a number of pulses different -greater, in this embodiment, but possibly smaller in other embodiments, as will be explained hereinafter - than that which it receives during the said zeroing operation, viz. the sensing parameter will deviate from its reference threshold value and reach its activating or upper threshold value. The computer is so programmed as to send to the controlled device, whenever this occurs, an appropriate activating instruction, which will depend on the nature and operation of the controlled device, on the particular sensor to which the sensing parameter relates, and optionally on other conditions or parameters which the computer has been programmed to take into account. As noted, the controlled device may be any conventional device for creating electric or electronic signals or signals of another kind, e.g. an interface, or a terminal apparatus, viz. an instrument or device for producing the finally desired effect, such as musical tones or optical images, the actuation of a safety device, and so forth, or even another computer. It will be understood that the computer may merely register that there is a dynamic stimulus, and therefore produce in all cases a single output instruction associated with the particular sensor which has received the dynamic stimulus, regardless of the intensity of this latter, or it may take that intensity into account and output instructions which are a function of it, viz., in the example described, a function of the number of pulses received during the measuring cycle, to cause the controlled device to produce effects of 2068/92 different intensities, e.g. stronger or weaker musical tones.

In this embodiment, each segment of the apparatus is provided with an emitter. However, as has been noted, a single emitter may be used for the whole apparatus. In this case, during the zeroing operation the emitter will beam its radiation towards the ceiling and the radiation reflected by the ceiling is that which will be sensed by the sensors. In the zeroing operation there is no obstacle between the ceiling and the sensors and the reflected radiation received by these latter is at a maximum. When a player operates the apparatus, he will intercept with his body part of the reflected radiation and the intensity of the radiation received by the sensors will be lower than during the zeroing operation. In other words, the dynamic stimuli will consist in a decrease of the intensity of the radiation received by the sensors. The apparatus will be so arranged as to respond to such decrease in the way in which it responds to an increase thereof in the embodiment previously described, viz. it will generate an ON signal in response to decrease of the sensed radiation below the lower limit established in the zeroing operation - which operation is analogous to that previously described - and an OFF signal in response to an increase of the sensed radiation above the upper limit established in the zeroing operation.

Fur er to illustrate the invention, a microcontroller program for one sensor/emitter couple is reported hereinafter. The program is written in C language. The term "MIDI" indicates a musical instrument digital interface (a protocol used by all electronic musical instruments) PROGRAM /* beginning of program */ int SDT, IN, EDN, ONIN, OFFIN; /* variables */ const int ISDT=1, NN=10, SN=5, cycle time=30 ^constants */ main () { zeroing () ; /* zeroing phase */ while (0==0) /*continues normal operation */ { IN=measure_cycle ( ) ; /* measure and get result */ if ( IN>ONIN ) .out on (); /* send on signal */ if ( IN (64-CSN+NN) ) ) /* proceed until SDT is proper */ { SDT=SDT+1; IN=measure cycle () ; } /* leaving only if SDT proper */ IDN=measure cycle (); OFFIN = IDN+SN; ONIN = IDN+SN+NN; } /* end of program */ This program should be completed and compiled according to the microcontroller which is used. 2068/92 We used: "INTEL" - 8051 microcontroller.

The emitters used: "OPTEK" - OP240 IREDS.

The sensors used: "SEIMENS" SFH205 PIN-PHOTODIODES with TBA2800 amplifier.

It will be understood that the method which is carried out by the apparatus described in the aforesaid example may be carried out by using radiations which are different from infrared radiation, e.g., ultrasonic waves or microwaves, and in such cases the apparatus will be adjusted to emit and receive the particular radiation that is being used, and the system which involves producing pulses and counting the number of pulses received in a given time interval can still be used, but in other cases, the sensing parameter may not a number of pulses. It may be, e.g., a direct measure of a radiation intensity, e.g. a tension or current produced by a photoelectric cell and the correlation between sensing parameter and physically definable characteristic of the radiation may be determined by the fact that the sensitivity of the cell may be adjusted so that said tension or current have a predetermined, reference threshold value in the absence of dynamic stimuli, the instruction output by the computer, when the apparatus is in use, being a function of the difference between the tension or current produced and their reference threshold values. In other cases, sensing parameter and radiation characteristic may coincide and the instructions output by the computer will be a function of the difference between the value of the characteristic in the absence and in the presence of dynamic stimuli. 2068/92 This may occur, e.g., when the radiation characteristic is the time gap between the emission of a radiation and its reception by the sensor. However, in this case too the radiation may be produced by pulses and said time gap be measured for each pulse. The computer will then zero the apparatus by registering for each sensor the said time gap in the absence of dynamic stimuli. It will then register the time gap in the presence of such stimuli and output an instruction which is the function of their d fference.

A more specific embodiment of the invention is described herein after with reference to Figs. 5 and 6.

The embodiment in question has two kinds of control outputs: 8 bit parallel - to control video/computer games - and serial - to control musical instruments with MIDI protocol.

With reference to Fig. 2, the following components are used: lens 27, focal length 5 cm; lenses 20 and 32, cylindrical, focal length 1.5 cm; mirrors 22 and 25, front coated aluminum.

The emitter is placed in the focus of the emitter assembly and the sensor is placed in the focus of the sensor assembly. The lens 32 is placed empirically in order to achieve the desired sensing beam, preferably between 0.5 cm and 1.5 cm from the sensor. 2068/92 The zeroing procedure hereinbefore described has been applied to the said apparatus in various rooms and it has been found that the values NN = 10 and SN = 5 are optimal values for most environments. In a room with a 2.5 m white ceiling the following values were found : SDT = 5 and IDN = 30. All the remaining parameters were calculated using the values of NN and SN. The operating height achieved was 1.2 m for a standard dynamic stimuli object equivalent to a child's hand. The aforesaid results are for the worst segment. In a room with a 2 m white ceiling the following values were found: SDT = 8 and IDN = 34. The operating height achieved was 1 m using the same standard dynamic stimuli object.

For further illustration lists of electronic components conveniently usable for the control circuit and the panel circuit of Figs. 5 and 6 are reporting hereinafter.

The said panel circuit and control circuit are related to the elements of the block diagram of Fig. 4 as follows: The emitter circuit of Fig. 4 includes elements D2, Ql, IREDl, R2, C3 and Dl. The remaining components of the panel circuit are included in the sensor circuit. 2068 92 Elements J2, U2, DZl , R6, R5, R4, R3, R2, Ql and Q2 of the control circuit form part of the units processor interface of Fig. 4. Elements Ul , XI , Cl , C2, C3 and Rl of the control circuit form part of the center processor of Fig. 4. Elements U3 and J4 for operating a computer device, and Ul serial output (pin 10) and J3 for operating an MIDI device which are in the control circuit, form part of the controller device interface of Fig. 4. 2068 92 RTT1, OF FT CTRONIC COMPONENTS CONTROT, CIRCUIT 1. Semiconductors Item Quantity Reference Characteristic R comm nded Part Ul Microcontroler 8051 **4KBYTE ROM lusec cycle 6 I/O bits for panel control serial port for midi 8 I/O bits for *external service U2 8 line 4051 Analog Multiplexer U3 latch/buffer 74373 for * external device U4 voltage LM317L regulator 7.5V lOOmAmp U5 voltage LM78L05 regulator 5V lOOmAmp Q1. Q3 small signal 2N2222 low freq switching trans transistor VCE=10V IC=50mAmps NPN Q2 small signal 2N2907 low freq switching transistor VCE=10V IC=50mAmps 2068 92 PNP 8 Zener diode 4.9V 0.25W 9 visible LED 50mAmps 10 XI crystal 12MHZ 2. Capacitors Item Quantity Reference Characteristics Recommended Part 11 C6, C7, C8 IC's decoupling caps 10NF 12 2 CI, C2 30PF 13 1 C3 power on reset 10UF 10V 14 C4 regulator decoupling cap 2.2UF 15 C5 regulator decoupling cap 2.2UF 3. Resistors Item Quantity Reference Characteristics Recommended Part 16 2 R1. R3 IK 0.25W 17 2 R2. R7 10K 0.25W 18 2 R8, R4 200 0.25W 19 1 R5 2K 0.25W 20 1 R6 100 0.25W 2L 1 R9 560 0.25W 22 1 RIO 2.7K 0.25W 2068/92 4. Connectors Item Quantity Reference Characteristic,*? ^mmended Part 23 1 Jl power input 2 pin 10V 0.3Amps 24 1 J3 rnidi output 3 pin 5V low current 25 1 J4 *external device output 9 pin 5V low current *Required only if external device control operational **Required for complex configuration 2Kbytes sufficient for basic configuration 2068/92 r J , OF FT ECTRONIC COMPONENTS PANEL CIRCUIT 1. Semiconductors Item Quantity Reference Characteristics Recomm nded Part 1 1 Ul IR preamplifier TBA2800 70DB gain 2 1 IREDl near IR OP240A (Optek) radiation 3Amps peak current at lusec 300pps lOOmW power dissipation 3 1 PD1 wavelength SFH205 (Seimens) matches IREDl NEP=3.7E-14 [Watt Sqrt (Hz) ] 4 1 Ql VCC=10V 3Amps peak current at lusec 300pps lOOmW power dissipation HFE=200 5 1 Q2 small signal 2N2222 switching transistor VCC=10V IC=50mAmps 6 1 Dl rectifying IN4001 diode lOOmAmp 10V DZl Zener diode 5.1V 0.25W 2068/92 2. Capacitors Item Quantitv Reference Characteristics Recommended Part 8 1 CI 10N/10V 9 2 C2, C3 100U/6V 10 1 C4 2.2U/6V 11 1 C5 33U/6V 12 1 C6 1.5N/6V 3. Resistors Item Quantity Reference Characteristics Recommended Part 13 1 Rl 10 0.25W 14 1 R2 10K 0.25W 15 1 R3 IK 0.25W 16 2 R4. R5 100 0.25W While the invention is particularly applicable to the control of musical instruments or computer-operated visual games, it is applicable to the control of different apparatuses. For instance, it can be used as a safety device to prevent or discontinue operation of a machine, an elevator or the like, whenever a part of the body of an operator or any other person is located where it could be endangered by the operation of the machine. In this case the presence of such a part of the body of a person constitutes the dynamic stimulus which activates the apparatus according to the invention and the zeroing operation is conducted taking into account the nature of such dynamic stimulus. 2068 92 While some embodiments of the invention have been described it will be understood that the invention can be carried into practice with a number of variations, modifications and adaptations, without departing from the spirit of the invention or from the scope of the claims. 101016/2 38

Claims (31)

1. A self-calibratable controller for controlling a device upon detecting an object in an environment , comprising : a) activatable radiation means for sensing radiation in the environment and generating an output indicative of the sensed radiation; and b) control means responsive to the output of the activatable radiation means and having a regulatable sensitivity, said control means including i) self-calibration means for calibrating t the controller to operate in the environment, including means for activating the radiation means to sense radiation in the environment in a self-calibration state in which the object is absent from the environment; ii) means for determining a reference parameter indicative of the radiation sensed in the self-calibration state; iii) operating means for maintaining the radiation means activated to sense radiation in the environment in an operating state in which the object is present in the environment; iv) said determining means being further operative for determining a sensing parameter indicative of the radiation sensed in be operating state; 101016/2 39 v) means for comparing the reference and sensing parameters, and for responsively generating an output control signal to control the device; and vi) means for regulating the sensitivity of the control means to the output of the radiation means during the self-calibration state.

2. The controller according to claim 1; and further comprising a support for supporting the radiation means, and wherein the radiation means includes emitter means for emitting a light beam into an emission space, and sensor means for sensing light over a sensing space, said spaces extending away from the support and at least partially overlapping each other in an overlapping region .

3. The controller according to claim 2, wherein the emitter means includes an infrared light source, and wherein the sensor means includes an infrared sensor.

4. The controller according to claim 2, wherein the radiation means includes means for shaping at least one of said spaces to have a generally thin, screen-like volume having a cross-sectional width and a cross-sectional thickness less than said width substantially throughout its volume .

5. The controller according to claim 4, wherein the shaping means includes a cylindrical lens. 101016/2 40

6. The controller according to claim 1, wherein the radiation means includes sensor means for receiving the radiation having a variable intensity, and wherein the determining means includes means for measuring the intensities of the received radiation as the parameters in both states.

7. The controller according to claim 6, wherein the radiation means is pulsatable, and further comprising means for pulsing the radiation means to generate radiation pulses, and wherein the determining means is operative for counting how many of the radiation pulses are generated in each state over a measuring cycle.

8. The controller according to claim 6, wherein the radiation means is pulsatable, and further comprising means for pulsing the radiation means to generate radiation pulses having pulse widths, and wherein the determining means is operative for measuring the pulse widths in each state over a measuring cycle.

9. The controller according to cairn 1, and further comprising means for periodically updating the reference parameter .

10. The controller according to claim 1, wherein the control means includes means for establishing a predetermined operating parameter, and for gernerating the output control signal when the sensing parameter exceeds the predetermined operating parameter. 101016/2 41

11. The controller according to claim 1, wherein the control means includes means for establishing two predetermined operating parameters, and for generating an actuating signal for actuating the device when the sensing parameter is greater than one of the operating parameters, and for generating a deactuating signal for deactuating the device when the sensing parameter is less than the other of the operating parameters, and for generating a no-change signal when the sensing parameter is intermediate the operating parameters.

12. The controller according to claim 1, wherein the control means includes means for processing the output control signal to be indicative of a relative distance between the object and the radiation means.

13. The controller according to claim 1, and further comprising a support for the radiation means, the support including a plurality of housings; and wherein the radiation means includes a plurality of radiation assemblies, one on each housing; and wherein the control means is operative for activating the radiation assembly on each housing to determine the reference parameter for each radiation assembly.

14. The controller according to claim 13, wherein the housings are arranged adjacent one another, and wherein each radiation means includes means for shaping at least one of said spaces to have a generally thin, screen-like volume having 101016/2 42 a cross-sectional width and a cross-sectional thickness less than said width substantially throughout its volume, and wherein the volumes are arranged adjacent one another to form a curtain.

15. The controller according to claim 1, and further comprising a support for the radiation means, the support being mounted on a floor of a room in front of a human player having an appendage that serves as the object; and wherein the device is a video game associated with a display; and wherein the control means includes means for processing the output control signal to change a position of an image on the display.

16. A method of controlling a device upon detecting an object in an environment, comprisrng the steps of: a) calibrating a controller to operate in the environment by initially receiving radiation from the environment in a self-calibration state in which the object is absent from the environment , and determining a reference parameter indicative of the radiation received from the environment in the self-calibration state; b) placing an object in the environment; c) subsequently receiving radiation from the object in an operating state, and determining a sensing parameter indicative of the radiation received from the object in the environment in the operating state; 101016/2 43 d) comparing the reference and sensing parameters, and responsively generating an output control signal to control the device; and e) regulating the sensitivity of the controller to the radiation received.

17. The method according to claim 16, and further comprising the step of transmitting a light beam into an emission space in each state, and wherein the receiving steps are performed by sensing light over a sensing space that at least partially overlaps the emission space.

18. The method according to claim 17, wherein the transmitting and receiving steps include the step of shaping at least one of said spaces to have a generally thin, screen-like volume having a cross-sectional width and a cross-sectional thickness less than said width substantially throughout its volume.

19. The method according to claim 16, wherein the determining steps are performed by determining the intensities of the received radiation as the parameters.

20. The method according to claim 19, wherein the determining steps are performed by generating radiation pulses and counting how many of the radiation pulses are generated over a measuring cycle. 101016/1 44

21. The method according to claim 19, wherein the determining steps are performed by generating radiation pulses having pulse widths and measuring the pulse widths over a measuring cycle .

22. The method according to claim 16, and further comprising the step of periodically updating the reference parameter.

23. The method according to claim 16, wherein the comparing and generating steps are performed by establishing a predetermined operating parameter, and generating the output control signal when the sensing parameter exceeds the predetermined operating parameter.

24. The method according to claim 16, wherein the comparing and generating steps are performed by establishing two predetermined operating parameters, and generating an actuating signal for actuating the device when the sensing parameter is greater than one of the operating parameters, and generating a deactuating signal for deactuating the device when the sensing parameter is less than the other of the operating parameters, and generating a no-change signal when the sensing parameter is intermediate the operating parameters.

25. The method according to claim 16, and further comprising the step of processing the output control signal to be indicative of a relative distance between the object and a support. 101016/1 45

26. The method according to claim 16, wherein the device is a video game having a display; and further comprising the step of processing the output control signal to change the position of an image on the display.

27. A video game system, comprising: A) a display; B) a game processor means for processing game data and displaying the processed data on the display; and C) a self-calibratable , video game controller for interactively controlling the game processor means in response to detection of a player in an environment, said controller including a) activatable radiation means for sensing radiation in the environment, b) means for activating the radiation means to sense radiation in the environment in a self -calibration state in which the player is absent from the environment, c) means for determining a reference parameter indicative of the radiation sensed in the self -calibration state , d) operating means for maintaining the radiation means activated to sense radiation in the environment in an 101016/1 46 operating state in which the player is present in the environment e) said determining means being further operative for determining a sensing parameter indicative of the radiation sensed in the operating state, and f) control means for comparing the parameters, and for responsively generating an output control signal to control the game processor means.

28. ) The system according to claim 27, and further comprising a support for supporting the radiation means, and wherein the radiation means includes emitter means for emitting a light beam into an emission space, and sensor means for sensing light over a sensing space, said spaces extending away from the support and at least partially overlapping each other in an overlapping region.

29. The system according to claim 28, wherein the radiation means includes means for shaping at least one of said spaces to have a generally thin, screen- like volume having a cross-sectional width and a cross-sectional thickness less than said width substantially throughout its volume.

30. The system according to claim 27, and further comprising a support for the radiadion means, the support including a plurality of housings; and wherein the 101016/2 47 radiation means includes a plurality of radiation assemblies, one on each housing; and wherein the control means is operative for activating the radiation assembly on each housing to determine the reference parameter for each radiation assembly.

31. The system according to claim 30, wherein the housings are arranged adjacent one another, and wherein each radiation means includes means for shaping at least one of said spaces to have a generally thin, screen-like volume having a cross-sectional width and a cross -sectional thickness less than said width substantially throughout its volume, and wherein the volumes are arranged adjacent one another to form a curtain. LUXIATTO . -U«»TTO