EP1409292A1

EP1409292A1 - Lighting repeater system

Info

Publication number: EP1409292A1
Application number: EP02708525A
Authority: EP
Inventors: Grant Belben
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-07-20
Filing date: 2002-03-28
Publication date: 2004-04-21
Also published as: WO2003008233A1; GB0117729D0

Abstract

A system for repeating rearward facing lights of a motorcycle comprises a radio receiver secured to the rider's helmet. A receiver module (70) receives radio signals respectively representing the tail, brake and left and right indicator lights of the motorcycle and encoded in two ways. First the four different signals are differentially encoded to represent the vehicle lights individually and second the signals as a whole are unique, so that the system does not interfere with others. Signals (74) to (80) are decoded by a decoder (82) which sends corresponding clear outputs to cause repeater lamps (86) to (92) to illuminate, according to which motorcycle light is operated. The receiver is powered by a battery (94) which can be recharged from the motorcycle by way of a connector (22). Continuous depression of a switch (26) for five seconds automatically tunes the receiver to the transmitter.

Description

Lighting Repeater System

This invention concerns a system for repeating the rearward facing lights of a vehicle, particularly but not exclusively for repeating the rearward facing lights of a motorcycle at a higher level than such lights are normally disposed.

Like other motor vehicles, motorcycles generally carry several rearward facing lights, typically a tail light, a brake light and left and right indicator lights. Unlike other motor vehicles, motorcycles do not readily accommodate the elevation of such lights or repeaters therefore which has recently come to be seen as improving safety. Indeed, many motorcycles have their rearward facing lights relatively low so that they may not be clearly seen from following vehicles. Thus, for instance, at traffic signals, where vehicles tend to stop close together, a driver of car or truck may fail to see an indicator light on a motorcycle in front, with evidently hazardous consequences.

Various previous proposals have been made to provide elevated lights for motorcyclists, usually with attachments to a rider's helmet. For example, US Patent 5 207 500 (Rios) has auxiliary lights on a rider's helmet connected to the motorcycle lighting circuit by means of an electrical cable.

Apart from the inconvenience of having to connect and disconnect the cable every time the motorcycle is used, such a cable may be hazardous in the event of an accident. US Patent 4 760 373 (Reilly) is more convenient and safer than Rios, having a radio link between a motorcycle and an auxiliary light on the rider's helmet. Reilly recognises the need to encode the radio transmission "so that only the transmitter attached to the motorcycle can activate the helmet's light and not some other nearby transmitter," but it is limited to repeating the brake light of the motorcycle, which does not counter the problem of following motorists' failing to see the tail light or indicator lights. The arrangement of US Patent 4 891 736 (Gouda) provides radio-controlled repetition of both brake and indicator lights, but with no encoding of the radio transmission this would be prone to faulty operation through interference from other nearby transmitters. For completeness there may be noted a different approach, illustrated by International Patent Application W09836213 (Noga Negev), in which a sensor detects braking (and/or possibly turning) of the motorcycle and activates a helmet-mounted auxiliary light accordingly. The use of sensors in this way makes for a complicated and expensive system which may give false signals under Coriolis forces or if, for instance, the rider adjusts his position on the motorcycle. It is an object of the present invention to enable a plurality of rearward facing lights of a motorcycle or other vehicle to be repeated reliably and inexpensively.

Thus according to the invention there is provided a repeater system for repeating a plurality of rearward facing lights of a vehicle, which system comprises a transmitter including transducer means responsive to operation of each said light to cause the transmitter to transmit a radio frequency signal representative thereof and a receiver remote from the transmitter for receiving the signals transmitted therefrom, the receiver including repeater means having a plurality of lamps respectively corresponding to the lights, each lamp being arranged to be illuminated when a signal representative of the corresponding light is received by the receiver, wherein the signals are encoded in two ways: (a) respectively to represent individual lights and (b) to be unique to the system.

It will be noted that the invention allows (unlike Rios) a plurality of the vehicle's lights to be repeated (unlike Reilly) conveniently and (unlike Noga Negev) inexpensively whilst (unlike Gouda) avoiding interference with other nearby systems.

Preferably the transmitter is powered from the vehicle and the receiver is powered from a battery separate from the vehicle. The battery may be rechargeable, possibly from the vehicle, and to reduce power consumption the receiver may be arranged to switch a said lamp off when another is illuminated.

The transducer means is preferably responsive to a tail light, a brake light and left and right indicator lights of the vehicle.

The control means may include first encoding means operative to encode each signal to represent a corresponding light and second encoding means to encode each signal to be unique to the system.

The system may include switch means manually operable to switch the receiver on and off, and preferably continuous manual operation of the on-switch means for a first predetermined period - say not less than four seconds - conditions the receiver to respond to signals from the transmitter.

Preferably the transmitter becomes operative when an ignition switch of the vehicle is turned on, and, when the ignition switched is turned off, a lamp of the receiver may flash intermittently for a second predetermined period unless the receiver is switched off. It is to be understood that the invention has a variety of possible uses including the provision of lamps for a vehicle-drawn trailer and the activation of remote hazard-warning lamps in the event of a vehicle accident or breakdown, for which the transmitter may be movably locatable with respect to the vehicle. A particular use for the invention is to repeat the rearward facing lights of a motorcycle at an elevated level, in which case the receiver may be arranged to be worn by a rider of the motorcycle, for instance by attachment to the rider's helmet.

Other aspects of the invention will be apparent from the following description, which is made by way of example only with reference to the accompanying schematic drawings in which - Figures 1 to 3 show a radio receiver of the invention in plan, rear elevation and side elevation respectively;

Figure 4 is a block diagram of a radio transmitter of the invention for operation with the receiver of Figures 1 to 3; and

Figure 5 is a block diagram of the receiver of Figures 1 to 3. Referring first to Figures 1 to 3, the radio receiver shown therein has a casing of synthetic plastics material having an inner face indicated generally at 10 which is formed to fit closely against a motorcyclist's helmet and an outer face indicated generally at 12 which is rounded to reduce drag. The casing may be secured to the helmet by any suitable means such as double sided adhesive tape or hook and loop fastenings and may be permanently or detachably secured.

The receiver is designed to repeat, at helmet level, four rearward facing lights of the motorcycle, namely the tail light, the brake light and the left and right indicator lights. Thus the receiver includes a tail light repeater 14, a brake light repeater 16, a left indicator repeater 18 and a right indicator repeater 20. As will be described in more detail hereinafter each repeater includes a lamp (not shown in Figures 1 to 3) whereby it may be illuminated.

The receiver is powered from a rechargeable battery (not shown in Figures 1 to 3) and includes a recharging socket 22 and a neon indicator 24 for warning when the charge is becoming low. Whilst it is not considered necessary to describe these in detail nor show circuitry in the drawings, it is to be understood that the battery may be recharged from the vehicle in well- known fashion or by way of a separate battery charger. The receiver also includes a push-button switch 26 for turning the repeater means on and off alternatively.

Figure 4 illustrates a transmitter of the invention. A supply voltage from the motorcycle electrical system (not shown) is delivered to a transducer 40 by way of a line 42. The transducer 40 receives inputs 44, 46, 48 and 50 from, respectively, the motorcycle tail light, brake light and left and right indicator lights so that the transducer 40 is activated accordingly whenever one of those lights is operated. The transducer 40 delivers four corresponding outputs 52, 54, 56 and 58 to a radio transmitter module 60 so that the transmitter module 60 transmits radio signals corresponding to each of the lights when it is operated. The transmitter module 60 is a telecontrolli RTF3-XXX frequency- shift-key module with SAW resonator and antenna 62. Its working frequency is indicated by XXX in its type code, in this case 433.92MHz. The module is constructed as a hybrid circuit to which a microcontroller may be added for encoding. The microcontroller is an Atmel AT90S1200 chip incorporated in the transducer 40. The microcontroller receives inputs from the vehicle lights and sends encoded outputs to the transmitter 60. Receiving inputs discretely from the vehicle lights, the microcontroller sends discretely encoded outputs to the transmitters, whereby each signal transmitted by the transmitter is representative of a specific light. Further, for every repeater system, the microcontroller is programmed individually so that (at least for all practical purposes) every signal transmitted by the transmitter is unique to that system. In this way the system will not interfere with any other similar system in the vicinity, and vice versa.

Figure 5 illustrates the receiver of the invention. The receiver includes a radio receiver module 70 which is a telecontrolli RRF1-XXX-Y frequency-shift-key superheterodyne data receiver module compatible with the RTF3-XXX transmitter module. Although not detailed in the drawings, the receiver is arranged so that if the push-button switch 26 (Figures 1 to 3) is continuously depressed for five seconds or more, the receiver is automatically conditioned to receive the encoded signals from the transmitter of Figure 4. When the conditioned receiver receives signals from the transmitter it delivers outputs 74, 76, 78 and 80 corresponding respectively to operation of the tail light, the brake light and the left and right indicator lights of the motorcycle. The four outputs 74, 76 78 and 80 are delivered to a decoder 82 incorporating, like the transducer 40, an Atmel AT90S1200 8-bit RISC architecture microcontroller chip arranged to decode the outputs. This microcontroller thereby receives encoded inputs representative of the vehicle lights (and unique to the system) and sends clear outputs, by way of a four-gang relay block 84, to switch on repeater lamps 86, 88, 90 and 92. The receiver is powered from a NiMH battery 94, which is rechargeable and connected to the recharging socket 22 and, as will be understood from the foregoing description, the switch 26 enables the receiver to be turned on and off alternatively. The repeater lamps 86, 88, 90 and 92, which may be high-intensity light-emitting diodes, are incorporated respectively in the tail light repeater 14, the brake light repeater 16, the left indicator repeater 18 and the right indicator repeater 20 (Figures 1 to 3). The repeater lamp 86 is illuminated when the tail light of the motorcycle is on, the repeater lamp 88 is illuminated when the brake light is on (ie when the motorcycle's brakes are applied) and so on. Thus the invention repeats, at helmet level, the rearward facing lights of the motorcycle.

It is important that the signals between the transmitter and the receiver are encoded in two ways. First, there are four different signals differentially encoded to represent the four vehicle lights individually, so that when the motorcycle tail light is operated the corresponding repeater lamp 86 (only) will be turned on, and so forth. Above this however, the signals as a whole are arranged to be unique, for all practical purposes, so that there is no likelihood of the system for one motorcycle affecting that of another which happens to be nearby. This may be done, as indicated earlier, by individually programming the encoding/decoding means, or alternatively by including pseudo-random elements in the system.

Returning now to Figure 3, an IFNOT device 64 is included in the output lines 52 and 54 from the transducer 40 to the transmitter module 60. The device 64 is arranged so that if the output 54 corresponding to operation of the brake light is energised then the output 52 corresponding to the tail light is (if previously energised) automatically de-energised. In other words the transmitter module 60 does not transmit a signal corresponding to operation of the tail light when the brake light is operated. This significantly reduces the power consumption of the battery-operated repeater means, extending battery charge life and providing more margin for the other repeater functions. It is preferred to include the IFNOT device 64 in the transducer, which is mounted on and powered from the motorcycle, but its minimal power, weight or space requirements mean that it may easily be incorporated in the receiver instead. It having been established that the invention provides a simple and effective means of repeating the rearward facing lights of a motorcycle at an elevated level, some additional features of the invention not detailed in the drawings will now be discussed.

The transmitter of Figure 4 is connected to the electrical wiring of the motorcycle so as to become operative automatically whenever the ignition of the motorcycle is on. The receiver of Figure 5 is so arranged that, when the ignition of the motorcycle goes off, the cessation of operation of the transmitter is detected by the receiver and a lamp of the receiver then begins to flash, and continues to flash every thirty seconds for a period of thirty minutes as long as the receiver remains switched on. This serves two purposes. First, it provides a reminder to the motorcyclist to switch the receiver off when leaving the motorcycle. Second, it provides a beacon in case a rider is thrown from a motorcycle in an accident which causes the ignition to go off, warning other road users of the accident and possibly helping emergency services to find the rider. The transmitter is also operative when the motorcycle side lights are on, whether or not the ignition is on. This provides a safety signal. A motorcyclist needing to attend to a puncture or running repairs at night or in poor visibility may turns on the side lights of the motorcycle, which in turn causes the tail light repeater he or she is wearing to be illuminated. Thus other road users may see both the motorcycle and the motorcyclist.

Because motorcycle wiring is capable of sustaining a current of several amps, the transmitter circuitry is protected by a 500mA fuse. Also the voltage received from the motorcycle lighting circuits is isolated by a PC847 opto-isolator.

The receiver battery is regulated by a 7805 voltage regulator and rechargeable by means of a Maxim MAX713 fast charge battery charger powered from a DC line of the motorcycle.

In practice it is convenient to embody the receiver as a physically flexible unit, whereby it may readily be conformed to a helmet or fitted to a jacket. Such a receiver may be encapsulated in a flexible casing, of synthetic plastics material or of rubber, to prevent the ingress of moisture to which it will be exposed when worn, and also to prevent tampering. With a sealed casing it is preferred to replace the battery charging socket heretofore described by an inductive coupling arrangement having a pair of elements, one within the casing and the other connected to the motorcycle DC power source, the pair being placed in close proximity to effect inductive coupling during charging and held so by magnetic attraction. In practice the transmitter also has a sealed casing, but preferably hard. The receiver includes BC184 transistors to control illumination of the

(LED) repeater lamps. Both the transmitter and the receiver include brown-out protection, in the form of an Atmel AVR180 8-bit microcontroller, to prevent loss of data when the regulated voltage drops below 4V.

The system functions satisfactorily with half-wave reflection aerials of length (calculated as ¹/₂ x 71250/433.92) of 82.1 mm.

It will be appreciated that various modifications and adaptations of the system as described may be made without departing from the essence of the invention. For example, the receiver may be made to be attached to a motorcyclist's jacket rather than a helmet, and it may be incorporated in a decorative emblem or a logo. The system may also be embodied in quite different form, for instance to repeat the rearward facing lights of a vehicle on a trailer drawn by the vehicle, or to provide a hazard warning when a vehicle has broken down or crashed. Other modifications will be apparent to those skilled in the science.

Claims

1. A repeater system for repeating a plurality of rearward facing lights of a vehicle, which system comprises a transmitter including transducer means responsive to operation of each said light to cause the transmitter to transmit a radio frequency signal representative thereof and a receiver remote from the transmitter for receiving the signals transmitted therefrom, the receiver including repeater means having a plurality of lamps respectively corresponding to the lights, each lamp being arranged to be illuminated when a signal representative of the corresponding light is received by the receiver, wherein the signals are encoded in two ways: (a) respectively to represent individual lights and (b) to be unique to the system.

2. A repeater system as claimed in claim 1 , wherein the transmitter is powered from the vehicle and the receiver is powered from a battery separate from the vehicle.

3. A repeater system as claimed in claim 2, wherein the receiver is arranged to switch a said lamp off when another is illuminated, so as in use to reduce power consumed by the receiver.

4. A repeater system as claimed in claim 2 or claim 3, wherein said battery is rechargeable.

5. A repeater system as claimed in claim 4, including means to recharge the battery from the vehicle.

6. A repeater system as claimed in any preceding claim wherein the transducer means is responsive to a tail light, a brake light and left and right indicator lights of the vehicle.

7. A repeater system as claimed in any preceding claim wherein the control means includes first encoding means operative to encode each signal to represent a corresponding light and second encoding means to encode each signal to be unique to the system.

8. A repeater system as claimed in any preceding claim including on-switch means manually operable to switch the receiver on.

9. A repeater system as claimed in claim 8, wherein continuous manual operation of the switch means for a first predetermined period conditions the receiver to respond to signals from the transmitter.

10. A repeater system as claimed in claim 9, wherein said first predetermined period is not less than four seconds.

11. A repeater system as claimed in any preceding claim including off-switch means manually operable to switch the receiver off.

12. A repeater system as claimed in any preceding claim wherein the transmitter becomes operative when an ignition switch of the vehicle is turned on.

13. A repeater system as claimed in claim 12 wherein, when said ignition switched is turned off, a lamp of the receiver flashes intermittently for a second predetermined period unless the receiver is switched off.

14. A repeater system as claimed in any preceding claim wherein the signals are transmitted in the 433MHz band.

15. A repeater system as claimed in claim 14, wherein the transmitter comprises a frequency-shift-key transmitter module with a working frequency of 433.92MHz and the receiver comprises a frequency- shift-key superheterodyne receiver matched to the transmitter and having a bit rate of 9.6Kbps.

16. A repeater system as claimed in any preceding claim wherein the receiver is movably beatable relative to the vehicle.

17. A repeater system as claimed in any preceding claim including a plurality of said receivers.

18. A repeater system as claimed in any preceding claim wherein the receiver is physically flexible.

19. A repeater system as claimed in claim 18, wherein the receiver is encapsulated in a flexible casing.

20. A repeater system as claimed in claim 19, wherein said casing is of synthetic plastics material or of rubber.

21. A repeater system as claimed in claim 19 or claim 20 including an inductive coupling arrangement whereby a battery of the receiver may be recharged.

22. A repeater system as claimed in claim 21 , wherein said inductive coupling arrangement comprises a pair of elements, one within said casing and the other connected to a DC power source of the motorcycle, the pair being placed in close proximity to effect inductive coupling during charging and held so by magnetic attraction.

23. A repeater system as claimed in any preceding claim wherein the transmitter has a sealed casing.

24. A repeater system as claimed in any preceding claim for repeating one of a number of rearward facing lights of a motorcycle, wherein the receiver is arranged to be worn by a rider of the motorcycle.

25. A repeater system as claimed in claim 24, wherein the receiver includes means for attachment to a helmet for the rider.

26. A repeater system for repeating a plurality of rearward facing lights of a vehicle substantially as hereinbefore described with reference to and as shown in the accompanying drawing.