A Study Of The O-Mega™ Network, Inc.’s
Less Than Lethal Electrical Defense Units (EDU)
A Medical and Technical Report
Dr. Robert A. Stratbucker
Background
The use of tactical electronics is a humane and safe improvement in the tiered use-of-force scale generally accepted by law enforcement in the United States: The primary objective of the application of physical force is to insure the control of a suspect with the only minimum force necessary. The types of force an officer may utilize vary depending on the degree of resistance or aggressive behavior used by a suspect; the officer should always gain and maintain an advantageous position when in such a confrontational situation. The generally accepted use of force scale is as follows: mere presence; verbalization; firm grip and pain compliance; electronic tactical restraint , chemical irritant, stun batons and kicks; upper body control holds ( carotid choke holds ); firearms.
Scope of Report
This report is in specific response to your 1992 request to begin testing on a new tactical restraint unit called the X-Caliber™ versus two conventional “stun guns”, the Secret Agent , and the Super Stunner. This report covers these tests of your new tactical restraint unit, a tubular X-shaped device designated X-Caliber™. Uniquely the X-Caliber™ contains all the electronic circuitry inside a 35’’ black plastic handle. The two more conventional restraint units, the Secret Agent , a small single battery unit, and the Super Stunner, a dual battery unit, are electronically similar to the X-Caliber™.
Your request afforded me some latitude in the manner of testing employed. Both operational and destructive testing of all three models of unit were carried out. The operational tests employed were similar to those which I used on earlier devices supplied by other manufacturers. The results of all these tests have been reported in detail in the scientific literature over the past few years.
Medical Theory of Operation
The following discussion covers most of the technical characteristics of stun guns and similar restrain devices. The mechanism for the effectiveness of any stun gun type of restraint device is the interaction of the electrical impulses produced by the device with the nervous and muscular systems. This interaction usually produces some temporary incapacity in the performance of the muscular system and therefore assists control over the aggressive actions of the subject. Nerve and skeletal muscle tissue, although themselves differing rather substantially in certain specific characteristics of electrical stimulation are quite similar in their “excitability” by an electrical impulse.
Precise differentiation of which of these two types of tissue might respond to a particular electric impulse is made difficult by the fact that motor nerves directly activate muscles. Thus some of the muscular activity, which is produced by the stun gun impulse may indeed be caused indirectly by the nerve activation. This includes the incapacitive effect of the stun gun restraint devices. Such an effect is caused by both muscular and neutral excitation by the impulse emitted from the device. Most important in these tissue reactions is the magnitude, duration, shape, and repetition rate of the applied electric impulses.
Electrical energy in optimal amounts may stimulate to respond normally while higher energies may damage as well as stimulate the tissue. This tissue damage is primarily related to the heating effect of electrical current passing through the tissue. Each type of excitable tissue is most efficiently excited by characteristic electrical stimuli. To appropriately excite this tissue, the requisite precise characteristics of intensity ( voltage or current) and timing (pulse shape and duration) must be used. Deviation from optimum characteristics in either direction generally means that more electrical energy
must be injected to cause the same reaction, thereby reducing the efficiency and tending to promote thermal injury. Thus the same impulse that can maximally excite neural tissue may have no effect on the muscular tissue and vice-versa.
Nerve tissues favor brief duration stimuli while heart muscle requires much longer duration impulses to become activated. This is primarily due to the much higher electrical capacitance of heart tissue. The common output mechanism of stun gun restraint units generates extremely short duration impulses, each measuring only a few millionth of a second. These pulses are virtually ineffective in stimulating heart muscle no matter how intense the stimulus. These ultra short duration impulses are only slightly effective in stimulating nerves even though the intensity, as measured in terms of peak output voltage, is many times greater than the minimum amount necessary using impulses of optimal duration.
The extremely narrow pulse width of the stun gun output accounts in great measure for the lack of penetration to deep tissues. Although the peak output from the circuit is of such high voltage as to cause ionization of the air, producing ozone and awesome discharge arcs, the pulse width is so narrow that the physiologic response is transient and clearly sub-maximal. Cardiac tissue, normally far removed geographically from the point of application of the device, would not be stimulated due both to isolation and to the unique physiologic characteristics of heart tissue. Even with direct application of the device to heart tissue any deleterious effect is minuscule.
The physiologic principle governing these observations is known as “tissue chronaxie”. The principle relates stimulus intensity to stimulus duration and is not constant but varies widely from one tissue type to another. Depending on the physical and chemical surroundings of the tissue, the value of the tissue chronaxie may even vary from moment to moment.
The shorter the duration of an electrical impulse, the higher its intrinsic frequency
components. In case of stun gun restraint units, the major energy component of the shock pulses is actually in the radio frequency spectrum rather than the audible frequency
spectrum where most functional nerve and muscle stimuli are located. This results in the “skin effect” (does not necessarily imply human skin), a well known and predictable electrical phenomenon wherein high frequency electrical currents crowd to the surface of an electrical conductor such as the human body and may not penetrate to the deeper nerves and muscles beneath. It has been shown that for frequencies above one megahertz, most of the actual current path is concentrated in the upper few millimeters of the human skin. This phenomenon should not be confused with dielectric heating such as diathermy, an unrelated mechanism which can cause deep tissue warming.
In summary, very short duration pulses as produced by stun gun tactical restraint units are only marginally effective in stimulating excitable tissue. This is a desired circumstance in the design of restraint devices since the region of the body affected by the discharge of the pulse is quite limited, and therefore the effect on the body, no matter how long the device is applied, is brief. The device produces a short period of incapacitation and no significant residual effect such as burning or damage to tissue appears to be possible. The heart is not directly stimulated at all, and any potentially hazardous subtle or gross rhythm abnormalities of the kind associated with accidental electrocution are, practically speaking, not possible. Only deep penetration of lower frequency or direct electric current into tissue is potentially hazardous due to the thermal effects and possible arrhythmic excitation of the heart muscle.
A stun gun restraint device’s output, when operating normally and when used in the prescribed manner, is not a significant hazard to normal adults. Impulses delivered to the subject’s face and especially near the eyes are to be avoided. This is because of the exquisitely sensitive nature of facial skin and the tissues of the eyes. For these reasons, stun gun impulses to the face have not to date been specifically tested.
Omega Stun Guns
restraint devices are not medical devices. Omega Stun Guns makes no claim of diagnostic or therapeutic efficacy about the devices. Since no such claim is made, the device does not appear to fall under the jurisdiction of the Device Amendments to the Food and Drug Act-1976, which laws prescribe detailed testing of the new medical devices before manufacture. Also, the FDA imposes strict regulations for quality assurance in the manufacturing process of medical devices.
Physical Theory of Operation
All restraint devices such as the X-Caliber™, including the older and less familiar TASER, possess common elements of electronic design. The design is based on a transistorized relaxation oscillator which periodically transfers an electrical charge accumulated on a small timing capacitator into the primary winding of a high ratio step-up transformer. If the electrical parameters and operating conditions of the circuit are properly chosen, the secondary winding voltage will exceed the dielectric breakdown potential of the air gap separating the output terminals resulting in a distinctive succession of very brief discharge arcs. These arcs will occur with familiar auditory and visual characteristics.
The circuitry is conceptually quite similar to an automobile ignition system with the circuit parameters altered to achieve a more psychologically and physiologically effective discharge while maintaining non-lethality. Indeed, the analogy of the X-Caliber™ circuitry to an automobile ignition system is apt in that the destructive tests reveal a highly reliable automobile spark plug NGK-C6HSA as the primary circuit control switch. Conventional restraint devices routinely employ PC board elevated “X tracks” as the primary circuit control switch. The use of a commercial spark gap was a wise choice in the X-Caliber™ design because older stun guns which employed PC board spark gaps were subject to erosion and failure if used for extended periods of time. Since the likely scenario for the X-Caliber™ may entail extended use, the spark plug circuit provides a rugged enhancement to X-Caliber™unit.
Improved performance often comes at some expense to safety. However, the margin of safety in all three units is extremely high as confirmed in actual practice as well as with laboratory animals. In my opinion, the slight degradation of safety expected from the enhanced performance would not be significant.
The Secret Agent is a small single battery unit of conventional design. It has a peak voltage output of 80 KV across the output terminals. The profile is small and the unit readily lends itself to being carried in a pocket. The small profile and modest output voltage assign this unit to personal protection, where the intended use is in emergency personal defense situations.
Click here for Secret Agent Stun Gun full description or here for a Secret Agent demostration video.
The Super Stunner is capable of delivering a higher peak voltage, 120 KV versus 80 KV for the Secret Agent. To my knowledge, it is the only hand-held restraint unit employing “Resonance Augmentation”. The effect of resonance augmentation is to substantially enhance both the snapping sound emitted during the arcing mode as well as the brilliance of the arc itself. This enhancement occurs as the result of a specially designed high voltage capacitor electrically across the output of the step up transformer, but physically formed so as to reside unobtrusively in the head of the device. Resonance augmentation tunes the output transformer to resonate at the frequency of the principal sinusoidal components of the output pulses.
This familiar principle is used widely in other technologies, but was not available to restraint unit technology until recently because of the unavailability of suitable capacitors. This technological breakthrough appears to have resulted from an imaginative combination of capacitor advancements coupled with high voltage packaging techniques.
The higher pulse output voltage of the Super Stunner stun gun is a direct result of three component changes in this model as versus the Secret Agent:
1. Larger storage capacitor (0.47 μf versus 0.33 μf )
2. Larger battery supply (2 X 9V versus 1 X 9V)
3. Resonanance Augmentation versus no augmentation.
Once again, enhanced performance raises the question of possible diminished safety. In the case of the Super Stunner Stun Gun, this question is perhaps somewhat more than academic.
Animal experiments with the Super Stunner Stun Gun showed no effect on the cardiovascular system of the test swine. For more about stun guns and animal control, click here.
The primary frequency components of the Super Stunner Stun Gun are an order of magnitude or more greater than the highest frequency pulses known to affect the heart when applied anywhere to the body surface. This margin of safety is over and above other safety characteristics regarding low power external pulse energy applied to the body.
The X-Caliber™ is an electrically-active repelling device whose principle benefits appear to be in the ability to repulse an aggressor or mob at more than arms length. This is an improvement in operator safety and effectiveness in successfully coping with such dangerous situations.
The primary repelling and intimidating features of the X-Caliber™ are a multiplicity of awesome electric discharges from the X-shaped crossmembers located at the end of a long tube. Quite apart from the physical characteristics of the structure, the electric discharges have a commanding sight and sound. The arc discharge elements are located at the ends of the X members and are paired resulting in two nearly simultaneous large arcs on either side of the device.
In assessing the “worst case” safety considerations of the X-Caliber™, one must postulate a highly unlikely but uniquely possible situation with this device as compared to a hand-held restraint unit. One of the intrinsic safety margins in conventional hand-held restraint units results from the localized nature of any electric current delivered to a subject by the contact probes. In almost any imaginable circumstance of contact with a subject, the current flow pathway is limited to a very small area of non-critical skin and subcutaneous tissue. But assume for the moment that an assailant grabs two opposing arms on the X-Caliber™, one with each hand. In contrast to traditional stun guns, which can only create a vanishingly small current in the chest regardless of the application pattern of the probes, the scenario posited above with some of the current through the chest could increase this minuscule value somewhat. Electric Field Theory suggests that even in this scenario, most – perhaps 90+% - of the current would flow the path of least resistance and flow though both palms with very little current traversing the longer, higher resistance path through the thorax. In any event the safety factor due to the previously mentioned “skin effect”, which is attendant in all restraint unit devices, is operational and would be the dominant safety factor insuring subject immunity to electrical hazard.
The X-Caliber™ has the same peak potential (120 KV) as the Super Stunner (120 KV). It’s delivery is enhanced by having two output transformers, two batteries, and an even larger storage capacitor (0.66 μf). These factors, along with the resonance augmentation enhancements described above, serve to tailor the output of the X-Caliber™ to support multiple nearly simultaneous discharges occurring randomly over the active surfaces. The two output transformers have their secondary windings connected in series, not in parallel as might be expected. These circuit changes optimize the incapacitation ability.
Respectfully submitted this 4th of August, 1994.
Robert A. Stratbucker, M.D., Ph.D.
Click here for the author's Abbreviated Curriculum Vitae.
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