System for passing electrical signals through a living body

Abstract

A system for passing electrical signals through a living body has a transmitter on one side of a body for feeding thereto a predetermined electrical signal on at least two separate channels on respective different frequencies and a receiver on the other side of the body for receiving the signal on each of the channels. An evaluating unit connected to the receiver evaluates the received signals and selecting from them one signal for further processing.

Claims

1. A system for passing electrical signals through a living body, the system comprising: a transmitter juxtaposed with one side of the body for feeding thereto a predetermined electrical signal on at least two separate channels on respective different frequencies such that the transmitted signal on two channels passes through the body; a receiver on the other side of the body for receiving the signal on each of the channels after passage of the signal through the body; and evaluating means connected to the receiver for evaluating the received signals and selecting from them one signal for further processing.

2. The system defined in claim 1, wherein the receiver has individual band-pass filters for each of the channels.

3. The system defined in claim 2, wherein the filters are adjustable.

4. The system defined in claim 1, wherein the one signal is selected that is most free of interference.

5. In combination with two motor-vehicle seats adapted to hold a driver and a passenger, a motor-vehicle subsystem, and a control element for the subsystem within reach of both of the seats, a system comprising: respective signal-output elements in the seats; a transmitter connected to both of the signal-output elements for feeding thereto different signals each on at least two different channels at different respective frequencies such that the signals are applied to the driver and passenger and can be detected at the control element when the driver or passenger nears it; a receiver connected to the control element for receiving the signals on each of the respective channels after passage of the signals through the bodies; and evaluating means connected to the receiver and to the functional component for evaluating all of the received signals and selecting from them one signal for further processing and operating or impeding operation of the functional component depending on whether the selected signal is from the driver or the passenger.

6. The combination defined in claim 5, wherein the evaluating means selects a signal based on freedom from interference.

7. A method of passing electrical signals through a living body, the method comprising the steps of: inputting into one side of a body a predetermined electrical signal on at least two separate channels on respective different frequencies such that the inputted signal passes on the two channels through the body; a receiver on the other side of the body for receiving the signal on each of the channels; and evaluating means connected to the receiver for evaluating the received signals and selecting from them one signal for further processing.

8. The method defined in claim 7, wherein the one signal is selected based on freedom from interference and thereafter this one signal is used.

9. The method defined in claim 7, wherein the evaluating means is connected to a safety-related motor-vehicle functional component and the receiver is connected to a control element of the subsystem, the method further comprising the step of: only enabling the subsystem when the receiver receives codes on three of the channels.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the sole FIGURE of the accompanying showing a schematic diagram of the system of this invention.

SPECIFIC DESCRIPTION OF THE INVENTION

(2) As seen in the drawing a system 1 according to the invention for passing electrical signals through the body 2 or 2 of a living creature, in this case a person, is used for example, as illustrated in principle in the drawing, in conjunction with a vehicle seat 3 or 3 of a motor vehicle not otherwise illustrated. An operating element 4 can be actuated by the person 2, here the driver, in the seat 3 or by the person 2, here a passenger, in the seat 3. Here it is necessary to distinguish whether the element 4 is actuated by the driver 2 located in the vehicle seat 3 or by the passenger 2 located in a vehicle seat 3. For instance the element 4 could control a functional component 10 such as the radio or climate-control system that the driver 2 should not be operating while driving at high speed.

(3) A transmitter 5 outputs a coded signal specific to the vehicle seat 3 of the driver or the operator of the motor vehicle is assigned to the vehicle seat 3 occupied by the driver 2, and a transmitter 5 output a coded signal specific to the vehicle seat 3 of the passenger 2. These signals are fed to the bodies 2 and 2 in the vehicle seats 3 and 3 by respective coupling or antenna systems 6 and 6 provided in the vehicle seats 3 and 3.

(4) According to the invention, each of these signal is continuously outputted by the respective transmitter 5 or 5 at n different frequencies f.sub.1, f.sub.2 . . . f.sub.n. Accordingly these signals from the respective transmitters 5 and 5 to the coupling system 6 and from there are fed to the bodies 2 and 2. If the operating element 4 is actuated by the driver, the signal is then passed to a receiver 7. The receiver 7 is provided with a number of band-pass filters corresponding to the number of transmission frequencies outputted by the transmitters 5 and 5. The filters 8 each case can only pass the frequency f.sub.1, f.sub.2, or f.sub.n of a respective one of the outputted signals to a control or evaluation unit 9 of the receiver 7.

(5) Since each set of signals continuously outputted by each of the transmitters 5 and 5 is coded, it is possible for the evaluating unit to easily determine the seat occupied by the person with the hand or body part that was brought near enough to the control element 4 to pass its respective signal thereto. The receiver 7 can then ascertain with a high degree of reliability the vehicle seat from which the operating element 4 has been operated. Accordingly subsequent switching and/or control operations can be initiated, carried out or refused.

(6) A plurality of such transmitting units each assigned to a seat thus cooperate with the receiver 7 described above. The number of filters 8 on the receiver is adapted to the number of frequencies f.sub.1, f.sub.2 . . . f.sub.n used overall by all the transmitters of which only two are shown here.

(7) Since the signals of each transmitter are outputted continuously simultaneously at a plurality of frequencies specific to the respective transmitter, it can be ascertained with the highest degree of reliability in the receiver 7independently of any interference signals that may be presentwhen a signal relayed by the operating element 4 from the vehicle seat 3 or 3 from the operating element 4 should be actuated.

(8) As an alternative to the individual band-pass filters 8 described above, the receiver may also have one or a small number of variable band-pass filters.

(9) The selector or evaluation unit 9 of the receiver 7 selects an interference-free signal from the frequency signals received from the individual filters 8. The receiver 7 can then be tuned to this interference-free frequency signal.

(10) For this purpose the selector or evaluation unit 9 is suitable for scanning the frequency signals of the transmitter 5 until it receives an interference-free frequency signal.

(11) In case safety-related functions are to be initiated by means of the operating element 4, the receiver 7 can be preset so that enabling this safety-related or comparable function only takes place when at least for example three different frequency signals of a transmitter 5 or of a transmitting unit and thus of one of these associated frequency spectra have the same result.