Abstract:
An instrumentation absolute value differential amplifier ( 212 ) is used as part of an electroencephalogram, electromyogram or electrocardiogram to quantify the excitation state of a user, processing and transmitting this information as a control signal for a user feedback device. In one embodiment, this feedback device comprises a wireless sex toy ( 500 ) which responds to the sent control information, acting as a mind-controlled sex toy. This provides a simple, intuitive, aesthetically appealing interface for creating a unique sexual experience. The use of an instrumentation absolute value differential amplifier is sufficient to monitor the desired signals while reducing the number of parts required and allowing for less precise tolerances than traditional biological monitoring circuits, thus decreasing the cost of production.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of provisional patent application Ser. No. 61/910,248, filed Nov. 29, 2013 by the present inventor and Ser. No. 61/970,902, filed Mar. 27, 2014 by the present inventor. 
     
    
     BACKGROUND 
     Prior Art 
       [0002]    The following is a tabulation of some prior art that presently appears relevant: 
       U.S. Patents 
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                 A 
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                 A 
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                 A 
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                 A 
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                 Thomas Sullivan 
               
               
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                 A 
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                 A 
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                 B2 
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                 B2 
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                 Imboden 
               
               
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                 B1 
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                 Michael Wyllie, 
               
               
                   
                   
                   
                 Michael O&#39;Leary 
               
               
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                 B2 
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                 A 
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                 A 
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                 B2 
                 Sep. 2, 2014 
                 Olivier Nys, Francois 
               
               
                   
                   
                   
                 Krummenacher 
               
               
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                 A 
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                 A 
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                 A 
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                 Meleis 
               
               
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                 A 
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                 U.S. Pat. No. 4,899,064 
                 A 
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                 A 
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                 A 
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                 U.S. Pat. No. 4,575,643 
                 A 
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                 U.S. Pat. No. 4,663,544 
                 A 
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                 Haycock 
               
               
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                 A 
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       U.S. Patent Application Publications 
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                 Marc Van Hulle, 
               
               
                   
                   
                   
                 Nikolay V. Manyakov, 
               
               
                   
                   
                   
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                 Stanley Yang 
               
               
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                 Tan Thi Thai Le 
               
               
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                 A1 
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                 Lori Washbon, Emir 
               
               
                   
                   
                   
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                 Shinobu Adachi, Jun 
               
               
                   
                   
                   
                 Ozawa, Yoshihisa 
               
               
                   
                   
                   
                 Terada, Koji Morikawa 
               
               
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       Foreign Patent Documents 
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                 WO2008109699 
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                 A3 
                 Jan. 21, 2010 
                 Samuel Trewartha 
               
               
                 WO2011002092 
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                 Tomohiro 
               
               
                   
                   
                   
                   
                 Hayakawa 
               
               
                 WO2000056211 
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                 Kim Hyeong 
               
               
                   
                   
                   
                   
                 Seok 
               
               
                 WO2007096595 
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                 Paul Kenny 
               
               
                 KR20030090415 
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                 Nov. 28, 2003 
                 Hong Jang Sun, 
               
               
                   
                   
                   
                   
                 Kang Nam Cheon 
               
               
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                 Dietmar Betat 
               
               
                 DEI 02006034067 
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                 A1 
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                 Kai-Use Solter 
               
               
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       Nonpatent Scientific Publications 
       [0000]    
       
         Heath, R. G. (1972) Pleasure and brain activity in man: Deep and surface electroencephalogram during orgasm. Journal of Nervous and Mental Disease, 154, p. 3-18. 
         Moan, C. E., &amp; Heath, R. G. (1972) Septal stimulation for the initiation of heterosexual behavior in a homosexual male. Journal of Behavior Therapy and Experimental Psychiatry, 3, p. 23-30. 
         Mosovich, A., &amp; Tallaferro, A. (1954) Studies on EEG and sex function orgasm. Diseases of the Nervous System, 15, p. 218-220. 
         Cohen, H. D., Rosen, R. C. &amp; Goldstein, 1. (1976) Electroencephalographic laterality changes during human sexual orgasm. Archives of Sexual Behavior, 5, p. 189-199. 
         Sarrel, P. M., Foddy, J., &amp; McKinnon, J. B. (1977) Investigation of human sexual response using a cassette recorder. Archives of Sexual Behavior, 6, p. 341-348. 
         Semmlow, J &amp; Lubowsky, J. (1983). Sexual Instrumentation. Biomedical Engineering, IEEE Transactions on, BME-30, 6, p. 309-319. 
         Graber, B. &amp; Rohrbaugh, J. (1985) EEG during masturbation and ejaculation. Archives of Sexual Behavior, 14 (6), p. 491-503. 
         Holstege, G., Georgiadis, J. &amp; Paans, A (2003). Brain Activation during Human Male Ejaculation. The Journal of Neuroscience, 23(27) p. 9185-9193. 
       
     
       Nonpatent Circuitry Publications 
       [0000]    
       
         Nahhas, A. (2013). Differential Precision Rectifier using Single CMOS DVCC. International Journal of Computer Applications, 67, 7. 
         Carter, B. &amp; Brown, T. (2001). Handbook of Operational Amplifier Applications. Retrieved from: http://www.ti.com/lit/an/sboa092a/sboa092a.pdf 
         Jones, D. &amp; Stitt, M. (2000) Precision Absolute Value Circuits. Burr-Brown Application Bulletin. Retrieved from: http://www.ti.com/lit/an/sboa068/sboa068.pdf 
         Wong, J. A Collection of Amp Applications. AN-106 Application Note. Retrieved from: http://www.analog.com/static/imported-files/application_notes/28080533AN106.pdf 
         Carter, B. (2000) A Single-Supply Op-Amp Circuit Collection. Application Report. Retrieved from: https://courses.cit.cornell.edu/bionb440/datasheets/SingleSupply.pdf 
         Texas Instruments (2013) AN-31 Op Amp Circuit Collection. Application Report. Retrieved from: http://www.ti.com/lit/an/snla140b/snla140b.pdf 
         Texas Instruments (2013) AN-20 An Applications Guide for Op Amps. Application Report. Retrieved from: http://www.ti.com/lit/an/snoa621c/snoa621c.pdf 
         Zumbahlcen, H. (2007) Basic Linear Design. Analog Devices. Retrieved from: http://www.analog.com.library/analogdialogue/archives/43-09/EDCh %202%20other %20linear %20circuits.pdf 
         National Semiconductor (1978). Op Amp Circuit Collection. Retrieved from: http://www.ti.com/ww/en/bobpease/assets/AN-31.pdf 
         Gerstenhaber, M. &amp; Malik, R. (2010). More Value from Your Absolute Value Circuit—Difference Amplifier Enables Low-Power, High-Performance Absolute Value Circuit. Analog Dialogue 44-04 Back Burner. 
         St. Angel, L. (1992) Dual op amp takes absolute difference. EDN. Retrieved from: http://m.eet.com/media/1159670/6-7%20design %20ideas.pdf 
       
     
       Nonpatent Web Logs 
       [0000]    
       
         Scott, E. M. (2012, Nov. 24). Hacking My Vagina [web log post]. Retrieved from: http://scanlime.org/2012/11/hacking-my-vagina/ 
       
     
       Nonpatent Motion Pictures 
       [0000]    
       
         Bratter, S. (Producer), Catalano, P. (Producer) &amp; Brambilla, M. (Director). (1993). Demolition Man [Motion Picture]. United States: Warner Bros. 
         Everett. G. (Producer) &amp; Leonard, B. (Director). (1992). The Lawnmower Man [Motion Picture]. United States: Columbia TriStar &amp; New Line Cinema. 
       
     
       Nonpatent Presentations 
       [0000]    
       
         Machulis, K. (2007, October 6). “Getting The Message Across” Presentation at Arse Elektronika 2007. Retrieved from: https://www.youtube.com/watch?v=cfs3srL_F4k 
       
     
         [0029]    The prior art relevant to this design falls into 10 areas: Instrumentation Amplifier Circuits, Absolute Value Amplifier Circuits, publicly available prior art, scientific research on sexual arousal using Electroencephalogram (EEG), commercialized consumer EEGs, Biofeedback technology, Computer Controlled Sex Toys, Network based sex toys, Wireless Sex Toys and Biometric Feedback Sex Toys. 
       Instrumentation Amplifier Circuits: 
       [0030]    Instrumentation Amplifiers allow amplification of low-voltage signals by a specified gain; these amplifiers include input buffer circuitry that allows measurement of weak signals, such as occurs with biological voltage measurement. Texas Instruments provides technical specifications for building a basic instrumentation amplifier using either two or three operational amplifiers with a single power supply (Carter, 2000), as does Analog Devices (Zumbahlen, 2007) and National Semiconductor (National Semiconductor, 2002). Traditional instrumentation amplifier designs require dual power supplies and a large number of precision components, leading to expensive production costs. 
         [0031]    An instrumentation amplifier used in body composition analysis is described in U.S. Pat. Nos. 4,947,862, 1990; this circuit does not make use of absolute value analysis. A rail-to-rail input range instrumentation amplifier (U.S. Pat. No. 8,823,453, 2014) also does not use absolute value analysis. An instrumentation amplifier using high-impedance input bias is described in (U.S. Pat. No. 4,558,239, 1985)—this amplifier performs an absolute value comparison to a given magnitude, but does not output the absolute value for analysis. 
       Absolute Value Amplifier Circuits: 
       [0032]    There has been a substantial amount of work done on processing the absolute value of an electrical signal. The earliest such patents cover an absolute value computer (U.S. Pat. No. 2,822,474, 1958), operational rectifier (U.S. Pat. No. 3,311,835, 1967), precision rectifier (U.S. Pat. No. 3,531,656, 1970) and full-wave rectifiers (U.S. Pat. No. 4,575,643, 1986, U.S. Pat. No. 4,941,080, 1990 and U.S. Pat. No. 6,480,405, 2002). Similar absolute value amplifiers have been described in operational amplifier applications handbooks (Carter &amp; Brown, 2001 and Wong), as have precision absolute value circuits (Jones &amp; Stitt, 2000), an Absolute Value Amplifier with Polarity Detector (Texas Instruments, 2013), a Full-wave rectifier with an averaging filter (Texas Instruments, 2013) and a low-power, high-performance absolute value circuit (Gerstenhaber &amp; Malik, 2010). An analog gate/switching circuit (U.S. Pat. No. 4,663,544, 1987) provides for both buffering of an input signal and outputting the absolute value of this signal, but not the absolute value of a difference between two signals. So, these patents only describe circuits that can provide the absolute value of one electrical input. A related circuit allows absolute value full-wave rectification of a signal in comparison to a reference voltage (U.S. Pat. No. 5,703,518, 1997), but without amplifying this difference. 
         [0033]    The most relevant circuit designs involve amplifying the absolute value of the difference between two voltages, as is shown in a Circuit to obtain the absolute value of the difference between two voltages (U.S. Pat. No. 3,299,287, 1967), an Absolute value amplifier circuit (U.S. Pat. No. 3,546,596, 1970), a Precision absolute value amplifier for a precision voltmeter (U.S. Pat. No. 4,518,877, 1985) and an Absolute Value Differential Amplifier (U.S. Pat. No. 4,899,064, 1990). Similarly, a Differential Precision Rectifier (Nahhas, 2013) can be used to calculate the difference between two signals while a dual op amp can be used to compute absolute difference (St Angel, 1992). However, none of these amplifiers include buffers on input signals, making them unsuitable for low-impedance signal collection (as occurs with biological data). 
       Publicly Available Prior Art: 
       [0034]    Mental Control of Sexual Stimulation has long been viewed as science fiction. The motion pictures “The Lawnmower Man” (1992) and “Demolition Man” (1993) both show versions of hallucinatory helmets that allow users mental connection leading to orgasm. However, a practical, functional mind controlled sex toy has remained out of reach. Kyle Machulis (2007) proposed EEG as a potential sex toy, but failed to provide any specifics of how this could be done. Micah Elizabeth Scott (2012) described the possibility of induced feedback loops using sex toys; however, her implementation used an ultrasonic distance sensor instead of biometric feedback. 
       Scientific Research: 
       [0035]    While substantial scientific research has been conducted on the correspondence between sexual arousal/orgasm and electroencephalogram readings, the results of these studies are often contradictory. Mosovich and Tallaferro (1954) reported EEG during masturbation and orgasm in male and female subjects, finding low-voltage rapid activity during the early stages of arousal, followed during orgasm by high-voltage “paroxysmal three per second waves which are mixed with rhythmic alternating muscular discharges”—but only on subjects who showed “evidence of body tension”. Heath (1972) and Moan and Heath (1972) studied intracranial electrodes in a male and a female subject, finding paroxysmal spiking and intensified delta wave activity in the amygdalae/left caudate nucleus in association with orgasm. Cohen, Rosen and Goldstein (1976) demonstrated shifts in electrical energy through amplitude and frequency changes of EEG activity from dominant to non-dominant hemisphere during sexual arousal, asserting that EEG provides “a viable methodology for quantitative assessment of orgasmic response”. Sarrel, Foddy and McKinnon (1977) reported an observable change in scalp EEG accompanying orgasm, but did not quantify their description. Semmlow and Lubowsky (1983) describe EEG as “a convenient measure of orgasmic response”. However, Graber et al. (1985) were unable to replicate these experiments under controlled conditions, finding no specific correlation between EEG and arousal/orgasm. Graber&#39;s study did find predictable movement artifacts similar to those described by Mosovich and Tallaferro on some subjects; Graber&#39;s team discarded these as motion artifacts and/or activity in the brain&#39;s muscle control cortex. Holstege et al. (2003) mapped brain activation changes (specifically in the right neocortex and cerebellum) during ejaculation using Positron Emission Tomography, a related brain imaging technology. Thus, research on EEG has failed to find any specific electroencephalogram pattern that relates only to sexual arousal. However, the motion/muscle control artifacts discarded by Graber et al. provide correlations to sexual excitation that can be used to quantify arousal. 
       Commercialized Consumer Electroencephalograms: 
       [0036]    The original electroencephalogram, electrode and signal analysis concepts were developed within the scientific community, appearing in U.S. Pat. No. 2,318,207 (1943), U.S. Pat. No. 4,202,354 (1978) and U.S. Pat. No. 4,610,259 (1983). However, this technology was bulky and expensive, leading to use almost exclusively for scientific research. This paradigm changed in the early twenty-first century with the first consumer EEG toy: Interactive Product Line&#39;s Mindball (U.S. Pat. No. 7,988,557, 2011). This first game was also prohibitively expensive; further development within the consumer EEG field yielded cheaper and cheaper commercial EEG toys. Commercial EEG headsets (U.S. Pat. No. 6,154,669, 2000) allowed wearable EEG devices for consumer use. These toys were primarily aimed at a younger audience, promising to provide video game controls and learning/meditation software. While large corporations including Sony (WO2011002092, 2011), Mattel (U.S. Pat. No. 8,157,609, 2012 and US20130130799, 2013) and Panasonic (US20120191000, 2012) developed some EEG systems, the bulk of development was conducted by two smaller companies: Emotiv and Neurosky. Emotiv&#39;s patents cover electrode headset designs (US20070225585, 2007, WO2008109699, 2008 and U.S. Pat. No. 565,735, 2008) intended to support a number of electrodes in a futuristic case along with application-specific patents on interpreting user mental states through signal analysis (U.S. Pat. No. 7,865,235, 2011, US20070173733, 2007, US20070066914, 2007 and US20080218472, 2008). Neurosky&#39;s patents cover specific electrode designs (U.S. Pat. No. 8,301,218, 2012 and U.S. Pat. No. 8,396,529, 2013), circuit designs (U.S. Pat. No. 8,780,512, 2014) sensory evoked potential designs for controlling devices (U.S. Pat. No. 8,155,736, 2012) and Mental state detection within users (US20080177197, 2008). While several of these patents/applications describe mental state analysis using EEG, none specify a sex toy as a potential application. The closest is Neurosky&#39;s patent on stimulus-locked control of external devices using EEG (U.S. Pat. No. 8,155,736, 2012)—but this design is based on “a stimulus-locked average signal of a plurality of EEG signal samples”. This means that the design requires some known input (such as a visual cue) in order to function correctly. Another patent (U.S. Pat. No. 4,949,726, 1990) describes an apparatus responsive to changes in brainwave patterns. Similarly, Emotiv&#39;s U.S. Pat. No. 7,865,235 (2011) describes classification of mental states within a subject, but requires comparison to predetermined responses in order to attempt to gauge the user&#39;s emotional state. While a substantial body of work exists on EEG components and analysis methods, no commercial EEG allows control of a sex toy based on mental/facial states. 
       Biofeedback: 
       [0037]    The concept of creating a feedback loop using Electroencephalogram has been developed and patented by a variety of corporations, typically for therapeutic or training purposes. The earliest such patent involves training users to generate desired EEG signals (U.S. Pat. No. 4,928,704, 1990) within an auditory/visually controlled environment. Similar biofeedback work is covered in U.S. Pat. No. 6,097,981 (2000), which describes controlling a computer animation using an Electroencephalogram and infrared data transmission protocols. More generally, U.S. Pat. No. 6,090,037 (2000) covers modification of biorhythmic activity using a force-transducer belt to control user interaction. U.S. Pat. No. 5,692,517 (1997) describes allowing a user to control a device using Electroencephalogram and Electromyogram signals, but specifies calculation of quadrature, limiting the device to measurement of frequency for periodic signals. Similarly, U.S. Pat. No. 8,326,408 (2012) covers a training method for controlling physical objects using EEG, but requires capturing two brain waves and determining their coherence and performing frequency calculations to control an object for visual cues. This patent does not cover tactile or sexual feedback from an EEG system. Finally, WO2000056211 (2011) covers brain wave signal analysis using an external computer, but does not allow for integrated sensors and analysis hardware. So, while biofeedback work has been conducted, none of these biofeedback mechanisms allow for a sex toy as a potential application. 
       Computer Controlled Sex Toys: 
       [0038]    The concept of controlling a sex toy through a computer has been explored in a variety of methods. DE19709324 (1998) describes a microprocessor controlling the vibration intensity of “masturbation instruments” coupled to a walkman tape player. Ohmibod is currently the market leader in audio-responsive sex toys using similar methods, as described in U.S. Pat. No. 5,648,422 (1997). Computer-mediated methods of diagnosing premature ejaculation have also been developed (U.S. Pat. No. 6,814,695, 2004). Finally, WO2005082312 (2005) covers a body massager using a computer connection for wired control. However, none of these control schemes use biometric feedback for sexual pleasure. 
       Network Controlled Sex Toys: 
       [0039]    Sex toy control over internet and/or network architecture has been developed in detail. U.S. Pat. No. 6,368,268 (2002) describes a coupled visual display and stimulation device intended to allow long-distance stimulation and synchronization between stimulation and visual cues. Similarly, DE102004011397 (2005) describes remote toy control in conjunction with erotic media. DE102009014044 (2010) and WO2011077262 (2011) cover multi-console systems allowing more than two users to interact through a central server. DE10038271 (2002) describes a networked vibrator with combination mobile telephone and camcorder. None of these systems describe a biometric feedback control scheme. 
       Wireless Sex Toys: 
       [0040]    Wirelessly controlled and charged sex toys have been developed for commercial use, primarily by LELO, Inc. and JimmyJane, Inc. U.S. Pat. No. 7,643,795 (2010) describes a bluetooth-controlled remote vibrator with a separator transmission and receiver interface. JimmyJane&#39;s U.S. Pat. No. 7,938,789 (2011) describes an inductively chargeable massager (first described in U.S. Pat. No. 7,749,178, 2010) capable of responding to both direct and wireless user controls, with the possibility of being controlled by biofeedback (but only as part of a control network). US20040132439 (2004) describes a remotely controllable wireless sex toy that can be controlled either directly or through a computer network. LELO holds two design patents on wireless sex toy case designs (U.S. Pat. No. 665,093, 2012 and U.S. Pat. No. 664,932, 2012) along with a remote control personal massager application (WO2013006264, 2013). 
       Biometric Feedback Sex Toys: 
       [0041]    Several Biometric feedback massagers/masturbation devices have been proposed, but none have been commercialized. The first biometric massager patent is intended for use with a massage chair (US20020123704, 2002). A more specifically sexual patent application (KR20030090415, 2003) involves an integrated sex toy and biometric sensor. The first US patent application. Smart Sex Toys (US20060270897, 2006) mentions controlling a vibrator through biological data—specifically pulse rate, blood pressure, body temperature, muscle contraction, respiration rate, respiration intensity or galvanic response—but not electroencephalogram or electromyogram. DE102006034067 (2008) specifies a vibrator controlled by biological arousal as determined by a microphone, muscle contractions, resistance of the skin and/or heart rate. WO2010108491 (2010) and DE102009015371 (2010) both describe a similar vibrator controlled by a heart rate sensor (gathered using a belt, cuff or loop-like body). WO2007096595 (2007) describes a stimulation device operating on biometric data-again specified as heart rate, muscular contractions and/or galvanic skin response. 
         [0042]    The most relevant granted US patents that mention the possibility of neural feedback are U.S. Pat. No. 7,815,582 (2010) and U.S. Pat. No. 7,938,789 (2011), both of which specify wireless remote control massagers. In U.S. Pat. No. 7,815,582 (2010), this massager is capable of control under ZigBee protocols, which can include signals from biofeedback sensors. In U.S. Pat. No. 7,938,789 (2011), the massager capabilities are expanded to include biofeedback (including neural activity) under ZigBee control and to allow biofeedback information to be sent from the massager to an external transceiver. None of these patents/applications specify an electroencephalogram/electromyogram controlled wireless vibrator operating independent of a larger control network. This requirement of a control network increases the cost and device complexity to the end user, which is detrimental in the sex toy industry, where simplicity and ease of use are major selling points. 
       Advantages 
       [0043]    While several previous inventors have speculated about biometric feedback sex toys, these have not been commercialized. Electroencephalogram control of a sex toy sounds like science fiction, but the technology is very real—the first embodiment specified in this patent has been built as a functional prototype. The use of radio control protocols without requiring a sensor mounted inside the massager or a control network reduces production costs and makes the device simpler to use, while the location of the electroencephalogram/electromyogram sensor on an external headband wirelessly linked to a receiving vibrator gives the user a truly unique mind-controlled sexual experience. Use of an instrumentation absolute value differential amplifier circuit reduces the manufacturing cost of such a device by decreasing the number of components necessary and allowing for lower precision parts than traditional biological monitoring circuits. 
       SUMMARY 
       [0044]    In accordance with one embodiment an instrumentation absolute value differential amplifier circuit inside an electroencephalogram/electromyogram headband module wirelessly controls a separate remote vibrator, creating a mind-controlled sex toy. 
     
    
     
       DRAWINGS 
         [0045]      FIG. 1  is a circuit diagram showing the instrumentation absolute value differential amplifier isolated from any application circuit. 
           [0046]      FIG. 2  shows an application EEG circuit for use with the instrumentation absolute value differential amplifier. 
           [0047]      FIG. 3  shows a representation of software used for the detector in the application circuit. 
           [0048]      FIG. 4  shows a headband case representation for the application circuit. 
           [0049]      FIG. 5  shows the application headband paired with a wireless, radio controlled vibrator. 
           [0050]      FIG. 6  shows a typical single person use case. 
           [0051]      FIG. 7  shows a typical two-person use case. 
           [0052]      FIG. 8  shows an alternative absolute value amplifier design. 
           [0053]      FIG. 9  shows an alternative amplifier layout using multiple instrumentation amplifiers. 
           [0054]      FIG. 10  shows an application EEG circuit with a Driven Right Leg amplifier and electrode. 
           [0055]      FIG. 11  shows an application headband with a Driven Right Leg electrode. 
           [0056]      FIG. 12  shows an Electrocardiogram application of the Instrumentation Absolute Value Differential Amplifier. 
           [0057]      FIG. 13  shows an Electromyogram application of the Instrumentation Absolute Value Differential Amplifier. 
           [0058]      FIG. 14  shows an alternate embodiment using an internet connection between two partners. 
           [0059]      FIG. 15  shows a recording module for signal storage and later playback. 
           [0060]      FIG. 16  shows an application headband paired to a transceiver module for personal computer control. 
           [0061]      FIG. 17  shows an application headband paired to a transceiver module for video game interaction on a personal computer. 
           [0062]      FIG. 18  shows an application headband paired to a speaker with audio output. 
           [0063]      FIG. 19  shows an application headband paired to a Radio Controlled toy. 
           [0064]      FIG. 20  shows an application headband paired with a Graphic Display Output. 
           [0065]      FIG. 21  shows an alternative logic circuit for converting the amplified signal to a digital output. 
           [0066]      FIG. 22  shows an alternate application circuit using a complex filter. 
           [0067]      FIG. 23  shows a software flow chart using a Fast Fourier Transform processing algorithm. 
       
    
    
     LIST OF REFERENCE NUMERALS 
     Hardware Components: 
       [0000]    
       
           100  (a/b): Input Signal 
           102  (a/b): Buffer Amplifier 
           104  (a/b/c/d): Resistor 
           106  (a/b): Differential Amplifier 
           108  (a/b/c/d): Resistor 
           110  (a/b): Diode 
           112 : Output Signal 
           200 : Resistor (Bias) 
           202 : Resistor (Bias) 
           204  (a/b/c/d): Resistor 
           206  (a/b): Coupling Capacitor 
           208  (a/b): Electrode 
           210  (a/b/c/d): Zener Diode 
           212 : Instrumentation Absolute Value Differential Amplifier 
           214 : Capacitor 
           216 : Microcontroller 
           218 : Radio Transceiver 
           400 : Headband 
           402 : Vibrator 
           404 : Battery Casing 
           406 : Battery 
           408 : Printed Circuit Board 
           410 : Forehead Electrode 
           412 : Ear Electrode 
           414 : Power Switch 
           500 : External Wireless Vibrator 
           502 : Radio Transceiver (within external vibrator) 
           504 : Microcontroller (within external vibrator) 
           506 : Vibrating motor (within external vibrator) 
           800  (a/b/c/d): Resistor 
           802 : Gain Resistor 
           804 : Capacitor 
           806 : Diode 
           808  (a/b/c/d): Resistor 
           810  (a/b): Operational Amplifier 
           900  (a/b): Instrumentation Amplifier 
           902  (a/b): Gain Resistor 
           904  (a/b): Diode 
           1000 : Driven Right Leg Amplifier 
           1002 : Driven Right Leg Electrode 
           1200 : Arm Band 
           1202 : Chest Electrode 
           1204 : Reference Electrode 
           1300 : Arm Band 
           1302 : Muscle Electrode 
           1304 : Reference Electrode 
           1400  (a/b): Transceiver 
           1402  (a/b): Personal Computer 
           1404 : Internet Architecture 
           1500 : Transceiver 
           1502 : Microcontroller 
           1504 : Storage device 
           1506 : User Control 
           1600 : Transceiver 
           1602 : Personal Computer 
           1604 : Interaction Software 
           1700 : Video Game 
           1800 : Transceiver 
           1802 : Tone Generator 
           1804 : Speaker 
           1900 : Transceiver 
           1902 : Microcontroller 
           1904 : Toy Motor 
           1906 : RC Toy 
           2000 : Transceiver 
           2002 : Microcontroller 
           2004 : Graphic Display 
           2100 : Amplified Signal Input 
           2102 : Rectifier/Low-Pass Filter 
           2104 : Comparator 
           2106 : Digital Control Signal 
           2200 : Complex Filter 
         Software States: 
         a: Microcontroller Initialization 
         b: Transceiver Initialization 
         c: Sample Count/Accumulator Reset 
         d: Analog-Digital Conversion Start 
         e: Analog-Digital Conversion Polling Loop 
         f: Accumulator Addition 
         g: Sample Count Increment 
         h: Sample Count Comparison 
         i: Accumulator Value Conversion 
         j: Transceiver Output 
         k: Reset Fourier Buffer, Sample Count 
         l: Store value in Fourier Buffer 
         m: Perform Fast Fourier Transform 
         n: Convert FFT Values to Desired Output 
       
     
       DETAILED DESCRIPTION 
     FIGS.  1 , 2 , 4 - 7 —First Embodiment 
       [0155]      FIG. 1  shows the Instrumentation Absolute Value Differential Amplifier circuit diagram isolated from any application circuit. Input  100   a  is connected to Buffer Amplifier  102   a ; Input  100   b  is connected to Buffer Amplifier  102   b . The output of the buffer amplifier  102   a  is connected to Resistors  104   b  and  104   c ; the output of buffer amplifier  102   b  is connected to Resistors  104   a  and  104   d . Resistor  104   a  is connected to the positive input of Differential Amplifier  106   a  and Resistor  108   a ; Resistor  104   b  is connected to the negative terminal of Differential Amplifier  106   a  and Resistor  108   b . Resistor  104   c  is connected to the positive input of Differential Amplifier  106   b  and Resistor  108   c ; Resistor  104   d  is connected to the negative terminal of Differential Amplifier  106   b  and Resistor  108   d . Resistors  108   a  and  108   c  are connected to the circuit ground. Resistor  108   b  is connected to the output of Differential Amplifier  106   a , and Resistor  108   d  is connected to the output of Differential Amplifier  106   b . The output of Differential Amplifier  106   a  is also connected to the input of Diode  110   a ; the output of Differential Amplifier  106   b  is connected to the input of Diode  110   b . The outputs of Diode  110   a  and  110   b  are then connected to the circuit Output  112 . All four operational amplifiers required may be part of a single Quad Operational Amplifier package (such as the TLC274 amplifier), although other parts/packages may be used. 
         [0156]      FIG. 2  shows an application circuit for the amplifier shown in  FIG. 1 . Resistor  200  is connected to the circuit&#39;s positive voltage source and Resistor  202 . Resistor  202  is then connected to the circuit ground. Resistors  204   a  and  204   b  are connected to the junction between Resistors  200  and  202 . Resistor  204   c  is connected to Resistor  204   a  and Coupling Capacitor  206   a ; Resistor  204   d  is connected to Resistor  204   b  and Coupling Capacitor  206   b . Coupling Capacitor  206   a  is connected to Electrode  208   a  and Zener Diode  210   a ; Coupling Capacitor  206   b  is connected to Electrode  208   b  and Zener Diode  210   c . Zener Diode  210   a  is connected to opposing Zener Diode  210   b , which is connected to ground; Zener Diode  210   c  is connected to opposing Zener Diode  210   d , which is also connected to ground. The junction of Resistors  204   a  and  204   c  is connected to the input  100   a  of Instrumentation Absolute Value Differential Amplifier  212 ; the junction of Resistors  204   b  and  204   d  is connected to the input  100   b  of Amplifier  212 . The output  112  of Amplifier  212  is connected to capacitor  214 , which is connected to the circuit ground. The junction of Output  112  and Capacitor  214  is connected to Detector  216 , which in turn is connected to Radio Transceiver  218 . Electrodes  208   a  and  208   b  may be of a wet (requiring a conductive fluid/paste) or dry (not requiring a conductive medium) design, active (requiring power to operate) or passive (not requiring a power source). The Zener Diodes pairs may be replaced with Varistors or other electro-static discharge protection devices. Detector  216  might be a PIC16F1825 microcontroller, although other microcontrollers, logic circuits or hardware state machines may be used. A CC2500 radio transceiver can be used for Transceiver  218 , although other transceivers will suffice. 
         [0157]      FIG. 4  shows an external case layout for a headband  400 . This headband contains and supports all other components. A battery case  404  holds a battery  406  and switch  414 . An on/off power switch will suffice, but alternative switches, buttons, capacitive touch sensors or other sensors may also be used for this purpose. Two electrodes are placed in contact with the user&#39;s skin at the forehead (electrode  410 ) and ear (electrode  412 ). A printed circuit board  408  contains and connects all hardware circuitry used on the headband. 
         [0158]      FIG. 5  shows the headband  400  sending a wireless signal to an external vibrator  500 . This vibrator contains a Radio Transceiver  502  connected to a Microcontroller  504 . This microcontroller is then connected to a vibrating motor  506 . Remote-controlled vibrators such as Lelo, Inc.&#39;s Lyla model can be used for this purpose. Alternative wireless signals (such as Zigbee, Bluetooth, ANT or infrared) or a direct electrical connection can also be used for communication between the headband and vibrator. 
         [0159]      FIG. 6  shows a typical single-person use case for the proposed system. The headband  400  is worn by a user and supports all circuitry and sensors. The vibrator  500  is placed near the genitals or inserted into the vagina or anus of the user. 
         [0160]      FIG. 7  shows a typical two-person use case for the proposed system. The headband  400  supports all circuitry and sensors and is worn by a first user. The vibrator  500  is placed near the genitals or inserted into the vagina or anus of a second user. 
       Operation 
     FIGS.  1 - 7   
       [0161]      FIG. 1  shows the Instrumentation Absolute Value Differential Amplifier circuit diagram in detail. The inputs  100   a  and  100   b  are sent through the Buffer Amplifiers  102   a  and  102   b ; this serves to provide a lower source impedance and constant current for these signals, minimizing the effect of later amplification on the source signals. Differential Amplifiers  106   a  and  106   b  amplify the two signals in a crossed arrangement, such that Differential Amplifier  106   a  output is the inverse of Differential Amplifier  106   b . The Gain for differential Amplifiers  106   a  and  106   b  is set by the ratio of Resistors  108   a - d  to Resistors  104   a - d  (where Resistors  108   a - d  all have one Resistance value  108  and Resistors  104   a - d  all have another Resistance value  104 ); thus the Gain equals Resistance  108  divided by Resistance  104 . The Differential Amplifier  106   a  output is then Input  100   b  minus Input  100   c  (multiplied by the Gain). Similarly, the Differential Amplifier  106   b  output is then Input  100   a  minus Input  100   b  (also multiplied by the gain). This gain is sufficient at  500 , but other gains or resistance values may be used. These signals are then run through Diodes  110   a  and  110   b , which only allow positive values to pass through (negative voltages result in a negligible voltage on the Diode). Thus, output  112  sends the absolute value of Input  100   b  minus Input  100   a , multiplied by the Gain. This is accomplished without the need for precision matched resistors or dual power supplies, reducing component costs. 
         [0162]      FIG. 2  shows an application circuit for bio-electric monitoring using the Instrumentation Absolute Value Differential Amplifier. Two bias resistors ( 200  and  202 ) are used to establish an intermediate voltage between the circuit power source and circuit ground. This bias voltage may also be run through a buffer amplifier to stabilize the bias current. Resistors  204   a  and  204   b  transmit this bias voltage to the two input lines and reduce signal crossover between the two. Electrodes  208   a  and  208   b  carry electrical charges from bio-electric sensors; Coupling Capacitors  206   a  and  206   b  prevent the circuit voltage from feeding back to the sensors (and the subject wearing them). Said electrodes may be dry or wet (requiring conductive gel), of a passive or active design. Zener Diodes  210   a - d  provide electrostatic discharge (ESD) protection—normally these carry negligible current, but in the event of high voltage (such as that caused by a static shock) these shunt the voltage to the circuit ground. Other ESD protection devices (such as varistors) may also be used to prevent shock damage. Resistors  204   c  and  204   d  reduce the voltage from the electrodes to a level that can be interpreted by the Instrumentation Absolute Value Differential Amplifier  212 . This voltage is too small to be read by a typical Analog-to-Digital converter, so it is amplified by the Instrumentation Absolute Value Differential Amplifier  212 . A gain of 500 is sufficient for this purpose, although other gains may be used. The output of said Amplifier is then filtered using capacitor  214  (removing high-frequency noise). Other filters (of low-pass, high-pass, band-pass, band-stop or notch design, passive or active) may be used for this purpose. The resulting signal is then read by the analog-to-digital converter (or alternative input) of detector  216 . PIC16F1825 microcontrollers may be used for this purpose, although other microcontrollers/state machines/logic circuits will suffice. The detector sends control signals to a radio transceiver  218 , communicating the read voltage to another device. 
         [0163]      FIG. 3  shows a software flow chart for a program intended to run on the detector  216  (when this detector is a programmable microcontroller). This flow chart describes a continual-operation loop. State a initializes the microcontroller and analog-to-digital converter. State b initializes the radio transceiver. State c resets the accumulator and sample count values. State d begins a sample operation within the ADC. State e polls the ADC unit until a result is available (conversion has finished). Once this result is ready, it is stored in the accumulator in state f. The sample count is then incremented in state g. This sample count value is then compared to the desired number of samples in state h. This desired number is sufficient at  1024 , but other values may be used. If the number of samples has reached the desired value, then the accumulator value is translated into a signal that can be used within the transceiver in state 1. This translation can simply be dividing a constant term by the accumulator value, but other algorithms may be used (such as comparing the previous accumulator value to the current value and scaling appropriately). Algorithms may be optimized to provide a response proportional to the user&#39;s arousal or inverse to said arousal, creating a tantric state (deliberately prolonging the user&#39;s sexual experience). This value is then sent as a set of instructions to the radio transceiver in state j and the cycle repeats. The software continues operation until circuit power is depleted or the device is reset. This algorithm is sufficient to sample the application circuit for changes in the user&#39;s biological signals, but other algorithms may be used. This algorithm may also include any of several modifications, such as: checking whether the calculated result is within pre-defined thresholds to ensure valid electrical connections between the electrodes and the user, performing a Fast Fourier Transform on data accumulated within a storage buffer to extract only desired frequencies, storing accumulator values within a circular buffer and averaging this buffer to provide smoother transitions, calculating a baseline upon startup to compare with later accumulator values, and/or storing persistent user-specific data within the microcontroller to allow faster baseline calculation. 
         [0164]      FIG. 4  shows the headband  400  components in more detail. The headband  400  fits snugly over the user&#39;s head, keeping the forehead electrode  410  in contact with the forehead. The battery case  404  provides electrical connections between the battery and circuitry components and contains an on/off switch  414  for controlling power to the circuit. The battery  406  provides power to these same circuitry components. The electrodes  410  and  412  transmit electrical signals to the printed circuit board  408 . This printed circuit board contains all electronic components used within the Electroencephalogram reading circuit. The size, shape and material of the headband  400  may be varied to fit aesthetic and functional requirements. 
         [0165]      FIG. 5  shows the headband  400  paired to a receiving vibrator  500 . The vibrator contains a radio transceiver  502  which monitors radio frequencies for sent commands. Upon receiving a command, this information is sent to microcontroller  504 ; said microcontroller then alters the speed of vibrating motor  506  accordingly. 
         [0166]      FIG. 6  shows a typical single-person use case for the proposed system. The headband  400  supports and contains all electrical components. The vibrator  500  provides sexual stimulation to the user. 
         [0167]      FIG. 7  shows a typical two-person use case for the proposed system. The headband  400  supports and contains all electrical components and is worn by a first user. The vibrator  500  provides sexual stimulation to a second user. 
       DESCRIPTION AND OPERATION OF ALTERNATE EMBODIMENTS 
     FIGS.  8 - 23   
       [0168]    In another embodiment ( FIG. 8 ), buffer amplifiers are added to the absolute value differential amplifier developed by Lindo St Angel. The circuit uses an alternative differential absolute value amplifier to provide an absolute differential gain value of inputs  100   a  and  100   b . Buffer Amplifiers  102   a  and  102   b  are connected to the inputs  100   a  and  100   b , respectively. Resistors  800   a  and  800   d  are connected to the output of Buffer Amplifier  102   a . Resistors  800   b  and  800   c  are connected to the output of Buffer Amplifier  102   b . An amplifier  810   a  has a negative input connected to Resistors  800   a ,  808   b  and  802 . The positive input of amplifier  810   a  is connected to Resistors  800   b  and  808   a . The output of amplifier  810   a  is connected to capacitor  804  and the anode of diode  806 . Capacitor  804  is also connected to Resistor  802 . An Amplifier  810   b  has a positive input connected to the diode  806  cathode, Resistor  800   d  and Resistor  808   b . Resistor  808   b  is connected to ground. The negative input of amplifier  810   b  is connected to Resistor  800   c  and Resistor  808   c . The output of Amplifier  810   b  is connected to Resistor  808   b  and  808   c ; this output is then sent as Output  112 . 
         [0169]    The embodiment shown in  FIG. 8  provides an absolute value differential circuit with a specified gain. Two sets of Resistors ( 800  and  808 ) have uniform values. Resistance values for Resistors  800  and  808  provide the gain ratio, such that the gain is equal to Resistance  808  divided by Resistance  800 . The Resistor  802  and Capacitor  804  are added to compensate for poor phase margin and instability. The output  112  is then equal to the absolute value of input  100   b  minus input  100   a  multiplied by the gain. 
         [0170]    In another embodiment ( FIG. 9 ), two instrumentation amplifiers  900   a  and  900   b  are cross-connected to inputs  100   a  and  100   b  such that the positive input of amplifier  900   a  is connected to input  100   a  and the negative input of amplifier  900   a  is connected to input  100   b  while the positive input of amplifier  900   b  is connected to input  100   b  and the negative input of amplifier  900   b  is connected to input  100   a . The output of amplifier  900   a  is then sent through Diode  904   a , while the output of amplifier  900   b  is sent through diode  904   b . The cathodes of Diodes  904   a  and  904   b  are joined and connected to output  112 . Gain resistors  902   a  and  902   b  are selected to set the gain on each amplifier. 
         [0171]    The embodiment shown in  FIG. 9  performs absolute value analysis using two instrumentation amplifiers. The instrumentation amplifiers contain buffer amplifiers for enhanced signal quality and have a programmable gain set by Resistors  902   a  and  902   b . INA118 amplifiers may be used for this purpose, although other amplifiers will suffice. Each instrumentation amplifier outputs a voltage corresponding to the difference between input  100   a  and  100   b ; these differences are inverted. Diodes  904   a  and  904   b  allow only positive voltages to be transmitted, thus sending the amplified absolute value of the difference between input  100   a  and input  100   b  to output  112 . 
         [0172]    In another embodiment ( FIG. 10 ), the application circuit features a Driven Right Leg amplifier  1000  connected to the instrumentation absolute value differential amplifier  212 . This amplifier is connected to Driven Right Leg electrode  1002 . The Driven Right Leg electrode is clipped to the user&#39;s ear opposite the reference electrode (as shown in  FIG. 11 ). 
         [0173]    The embodiment shown in  FIG. 10  sends current back to the user&#39;s body in order to reduce unwanted noise in the collected data. The driven right leg amplifier  1000  buffers the electrical signals measured by the instrumentation absolute value differential amplifier  212 . These signals are sent back to the body through Driven Right Leg electrode  1002 . 
         [0174]    In another embodiment ( FIG. 12 ) the electroencephalogram headband is replaced with an electrocardiogram arm band  1200 . Two electrodes are connected to the arm band; Electrode  1202  attaches to the chest, while electrode  1204  attaches to the arm and provides a reference signal. 
         [0175]    The device shown in  FIG. 12  uses an instrumentation absolute value differential amplifier to measure heart activity; all other circuit function is similar to the Electroencephalogram processing circuit. The electrodes  1202  and  1204  are used as inputs to the instrumentation absolute value differential amplifier application circuit, while the arm band  1200  contains and supports all circuit components. 
         [0176]    In another embodiment ( FIG. 13 ) the electroencephalogram headband is replaced with an electromyogram arm band  1300 . Two electrodes are attached to the arm band—a muscle electrode  1302  and a reference electrode  1304 . 
         [0177]    The device shown in  FIG. 13  uses an instrumentation absolute value differential amplifier to measure muscle activity; all other circuit function is similar to the Electroencephalogram processing circuit. The electrodes  1302  and  1304  are used as inputs to the instrumentation absolute value differential amplifier application circuit, while the arm band  1300  contains and supports all circuit components. 
         [0178]    In another embodiment ( FIG. 14 ) the communication between the headband and vibrator makes use of a network architecture for transmitting data. Headband  400  sends data wirelessly to transceiver  1400   a , which is connected to personal computer  1402   a . The computer  1402   a  sends information through an internet architecture  1404  to a computer  1402   b . Computer  1402   b  has a transceiver  1400   b  attached; this transceiver sends a wireless signal to vibrator  500 . 
         [0179]    The system shown in  FIG. 14  uses network architecture to allow remote use of the headband-vibrator pair. Headband  400  generates data to be sent, which is received by Transceiver  1400   a . This transceiver encodes the wireless signal into computer-readable signals, which are interpreted by Personal computer  1402   a . Computer  1402   a  then sends these signals to computer  1402   b  using network architecture  1404 . Personal computer  1402   b  sends this information to linked transceiver  1400   b , which generates a wireless signal in response. This signal is sent to vibrator  500 , controlling the vibrator. 
         [0180]    In another embodiment ( FIG. 15 ) the headband-vibrator connection includes a module that allows storage and later playback of recorded signals. An intermediate transceiver  1500  is connected to microcontroller  1502 ; this microcontroller is connected to a storage device  1504  and user control  1506 . The transceiver  1500  is capable of receiving wireless signals from the headband  400  and sending wireless signals to a vibrator  500 . 
         [0181]    The embodiment shown in  FIG. 15  makes use of an intermediate transceiver  1500  to allow storage and later playback of recorded signals. This transceiver receives signals from headband  400  and sends them to microcontroller  1502 . The microcontroller stores these signals in storage device  1504 . The user control  1506  allows the user to record, playback or clear the storage device as desired. If the user desires playback, the microcontroller reads values from storage device  1504  and sends them to transceiver  1500 . These signals are then sent to vibrator  500 . 
         [0182]    In another embodiment ( FIG. 16 ) the headband is used as a control device for a personal computer  1602 . The computer is electrically connected to a receiving transceiver  1600  and has interaction software  1604  installed. 
         [0183]    The embodiment shown in  FIG. 16  allows the headband to be used as a control device for personal computer  1602 . The wireless signals generated by the headband are received by a transceiver  1600 , which transmits them to computer  1602  where they are interpreted using software  1604 . 
         [0184]    In another embodiment ( FIG. 17 ) the headband is used as a control device for a video game  1700  running on a personal computer  1602 . A transceiver  1600  is connected to computer  1602  running this video game. 
         [0185]    The embodiment shown in  FIG. 17  allows the headband to be used as a control device for video game  1700 . The wireless signals generated by the headband are received by a transceiver  1600 , which transmits them to computer  1602  where they are used as control inputs for video game  1700 . 
         [0186]    In another embodiment ( FIG. 18 ) the headband  400  is used as a musical instrument. The wireless signals generated by the headband  400  are received by a transceiver  1800 , which is electrically connected to tone generator  1802 . Tone generator  1802  is connected to a speaker  1804 . 
         [0187]    The embodiment shown in  FIG. 18  allows the headband to be used to generate auditory tones. The wireless signals generated by the headband  400  are received by a transceiver  1800 , which relays them to tone generator  1802 . The tone generator creates auditory signals in response to measured physiological states and sends them to speaker  1804 . Speaker  1804  transforms the electrical signals into sound. 
         [0188]    In another embodiment ( FIG. 19 ) the headband  400  is used as a controller for a remote-control toy  1906 . The toy  1906  contains a transceiver  1900  which is electrically linked to a microcontroller  1902 . The microcontroller  1902  is linked to one or more toy motors  1904  within the RC toy which control some parameter of the toy action (such as a toy car&#39;s speed). 
         [0189]    The embodiment in  FIG. 19  allows the headband  400  to be used as a controller for a remote-control toy  1906 . Transceiver  1900  within the toy receives signals sent from headband  400  and sends them to microcontroller  1902 . This microcontroller uses the received signal to set the speed of one or more toy motors  1904 , thus changing the control of toy  1906 . 
         [0190]    In another embodiment ( FIG. 20 ) the headband  400  is used as a controller for a graphical display  2004 . The graphical display  2004  contains a transceiver  2000  which is electrically linked to a microcontroller  2002 . The microcontroller is linked to graphic display  2004 . 
         [0191]    The embodiment in  FIG. 20  uses the headband  400  control signal to change the state of a graphical display  2004 . A transceiver  2000  receives sent headband signals and relays them to a microcontroller  2002 . This microcontroller performs analysis of said signals and sends the results as instructions for graphical display  2004 . This display might be used to show the relative strength of the headband signals sent, the history of previous signals over a predetermined length of time, customized messages based on headband activity or other animation dependent on the headband state. 
         [0192]    In another embodiment ( FIG. 21 ) the detector is a logic circuit taking the amplified signal  2100  as an input. The signal is passed through a rectifier or low-pass filter  2102 , then a comparator  2104 . The output of this comparator is used as a digital control signal  2106 . 
         [0193]    The embodiment shown in  FIG. 21  works by low-pass filtering or rectifying the amplified signal  2100 . The rectifier/low-pass filter amplifies the low-frequency content of signal  2100 . A comparator  2104  then compares this signal to a given voltage. If the low-passed signal is greater than the given voltage, the digital output  2106  is set to a logic high state; if the signal is less than the given voltage, the output signal  2106  is set to a logic low state. 
         [0194]    In another embodiment ( FIG. 22 ) the capacitor is replaced with a complex filter  2200  within the application circuit. 
         [0195]    The embodiment shown in  FIG. 22  works to allow complex filtering of the amplified signal, providing either a low-pass, high-pass, band-pass or band-stop filter depending on the filter characteristics of filter  2200 . 
         [0196]    In another embodiment ( FIG. 23 ) the microcontroller software makes use of frequency analysis with a Fast Fourier Transform and a Fourier buffer for sample storage. The software includes four additional states; in state k, a Fourier buffer is reset. In state 1, values are added to the Fourier Buffer. In state m, the Fourier Buffer is analyzed using a Fast Fourier Transform (FFT). In state n, the output of the FFT is converted to the desired transceiver output. 
       CONCLUSIONS, RAMIFICATIONS AND SCOPE 
       [0197]    Thus the reader will see that at least one embodiment of the mind-controlled sex toy provides a unique, novel yet economical device for sexual stimulation. While my above description contains many specificities, these should not be construed as limitations on the scope, but rather as an exemplification of one embodiment thereof. Many other variations are possible. For example, various safety features could be substituted, using paired transistors, coupling capacitors, varistors or other combinations of components to prevent electric shock to the user/device. The absolute value function could be performed by a rectifier circuit, with differential amplification performed prior to this rectifier. A virtual ground could be used to allow the Instrumentation Absolute Value Differential Amplifier to output values relative to a non-ground voltage. A single input signal could be buffered and compared to an internally generated voltage level instead of the second input signal. The coupling capacitors and/or resistors could be removed from the application circuit, allowing voltage levels to be read directly from the electrodes. The differential circuit and gain circuits could be separated such that a difference between two buffered input signals is first generated, then multiplied by a gain factor in a second stage. A power supply could be added to provide a constant voltage value. The filter could be implemented in hardware or software, of a low-pass, high-pass, band-pass, band-stop or notch design, active or passive. The microcontroller could be replaced with a hardware-specific state machine or other logic circuit. The paired sex toy could be a vibrator, penis pump, fleshlight, or other masturbatory/sexual aid. The communications protocol used to send data could be RF, ZigBee, Bluetooth, ANT, infrared, near field communication or other wireless transmission format. The wireless communication could be replaced with a direct electrical connection. The toy could either directly pair with a masturbatory aid or make use of a computer network to send control signals over long distances. The biofeedback information gathered could be stored and transmitted/replayed at a later time. The analysis algorithm could make use of a Fourier transform, frequency filtering, moving average, phase locked loop or other computational signal processing method. The means of controlling the device could be a push button, radio signal, graphical display, capacitive touch sensor or alternative user interaction device. The electrode sensors could be simple metal plates, wet or dry conductive electrodes, contoured to fit the user&#39;s skin or shaped as desired. The exterior case for the electroencephalogram could be a headband, set of contoured plastic bands or other electrode casing. The receiving device may be an RC toy, monitoring software, a wireless sex toy or another coupled device. The bio-electric sensors may be connected to the user&#39;s head (forming an electroencephalogram), chest (electrocardiogram), muscles (electromyogram) or other body locations. Accordingly, the scope should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents. 
       GLOSSARY OF TECHNICAL TERMS 
       [0198]    Amygdalae: A brain area that performs a primary role in memory, decision making and emotional reaction.
 
Analog-to-Digital Converter (ADC): A device used to convert analog signals into digital representations, which are typically used to allow mathematical operations and storage within a microcontroller.
 
ANT: Wireless technology standard designed for sensor networks.
 
Bias Voltage: A voltage added to input values in order to ensure that signals are within the range that can be interpreted by an amplifier.
 
Bluetooth: Wireless technology standard for exchanging data over short distances.
 
Buffer Amplifier (Hardware): An operational amplifier circuit that takes one input signal and produces one output signal with a similar voltage, but larger current (which isolates the original signal from noise caused by later amplification).
 
Buffer (Software): A portion of memory allocated for temporary storage.
 
Capacitor: A passive component that acts as a charge barrier, allowing high-frequency signals to pass through but blocking low-frequency ones.
 
Circular Buffer: In software, a portion of memory allocated for temporary storage where values are overwritten in a pre-determined order, minimizing the number of reads/writes within the buffer.
 
Delta Wave: A brain wave signal with a frequency of oscillation between 0 and 4 hertz.
 
Differential Amplifier: A specific operational amplifier configuration that outputs the difference between two signals multiplied by a gain value.
 
Diode: Electronic component that allows current to flow in only one direction.
 
Dominant Hemisphere: The brain hemisphere opposite to an individual&#39;s preferred body side (for example, a right-handed person is typically left-brain dominant).
 
Driven Right Leg electrode: Electrode connected to the difference amplifier used to counteract frequencies in the human body resulting from exposure to electrical devices. These devices produce a 50/60 Hertz frequency that is not a result of brain activity; addition of a driven-right-leg electrode eliminates this interference.
 
Dual power supply: A power supply making use of both positive and negative voltages.
 
Electrocardiogram (ECG/EKG): A device used to measure heart activity through electrical response.
 
Electrode: A conductive material that allows measurement of electrical activity from an external source.
 
Electroencephalogram (EEG): A device used to measure brain activity in terms of electrical response (voltage levels). Typically uses a Fourier transform to separate electrical activity by frequency range.
 
Electromyogram (EMG): A device used to measure muscle activity by tracking electrical response.
 
Electrostatic Discharge (ESD): Static shock caused by different voltage levels between a circuit and an external source rapidly equalizing. Typically involves very high voltage but low current.
 
Fast Fourier Transform (FFT): A method of computing a Fourier Transform that minimizes the amount of necessary calculation.
 
Filter: A combination of electrical components that selectively distorts the frequencies present in the signal passed through it, effectively strengthening the desired frequencies and diminishing undesired noise.
 
Fourier Transform: A mathematical operation that calculates the relative strength of different frequencies present within a signal.
 
Gain Resistor: Resistor used to set an amplifier&#39;s gain value.
 
Gain: The ratio of an output signal&#39;s voltage level to an input signal&#39;s voltage level.
 
Ground: The portion of a circuit used as a reference voltage (typically the lowest voltage in the circuit).
 
Impedance: Resistance to current flow (for analysis of either Direct or Alternating Current Systems).
 
Infrared: A form of short-range wireless communication using infrared light.
 
Instrumentation Amplifier: A specialized amplifier circuit that amplifies the difference between two low-current input signals. Typically composed of two buffer amplifiers used as inputs to a differential amplifier.
 
Left Caudate Nucleus: A brain area involved in voluntary movement.
 
Microcontroller: An integrated circuit containing a programmable computer which is capable of reading, storing, performing mathematical operations on and outputting electrical signals.
 
Near Field Communication: A form of short-range wireless communication that creates a modulated electric or magnetic field, but not the electromagnetic waves used in radio communication.
 
Operational Amplifier: An electronic component used to amplify, buffer or perform other high-speed operations on one or more input signals. Usually packaged in single, double or quad integrated circuits.
 
Positron Emission Tomography: A nuclear imaging technique that produces three-dimensional scans of functional processes within the body.
 
Precision Instrumentation Amplifier: An instrumentation amplifier manufactured using high-precision components.
 
Quadrature: Mathematics used to describe a sinusoidal wave 90 degrees out of phase with a base signal.
 
Radio Transceiver: An electrical component that converts electronic signals to/from radio signals and can be used to send or receive these radio signals.
 
Rectifier: A circuit used to generate an absolute value of a given signal. A half-wave rectifier only outputs positive input signals, while a full-wave rectifier outputs positive signals and the inverse of negative input signals.
 
Resistor: A passive component that converts electrical energy to thermal energy, resulting in a voltage drop proportional to the component&#39;s resistance multiplied by the current run through it.
 
RF: Radio Frequency control scheme—generally used to refer to wireless transmission.
 
Single power supply: a power supply using only a single positive or negative voltage.
 
Vcc: The circuit power supply.
 
Virtual Ground: A voltage level that is not the circuit ground, but is treated as such by connecting it to an operational amplifier (meaning that the amplifier outputs voltages relative to this value).
 
Zener Diode: A type of diode that has a stable breakdown voltage (meaning that very negative voltages cause it to transmit current, but less negative voltages do not).
 
ZigBee: Radio Protocol used to create personal area networks between devices.