|Title of Invention||
ANTI-COLLISION FOR RAILWAYS
|Abstract||This invention is about an anti-collision system for railways based on wireless communication. The invention is based on sending warning signals transmitted form engines of trains. These signals are sent from engines upon receiving commands from onboard processors which process information received from short range transmitters pairs located besides tracks. The processing of information by processor is carried out as per program made in accordance with logics indicated in tables. Special short range transmitter pairs are placed besides tracks in the event of train approaching a multiple track location or a junction so that the system is deactivated and once the train leaves these locations, the system is reactivated. The proposed system is not a replacement for existing signaling system. It is to be used in addition to existing signaling system.|
ANTI-COLLISION SYSTEM FOR RAILWAYS
Field of application
This invention relates to an anti-collision system for railways. This is achieved by employing a system of short range transmitters (range is of the order of 2 meters) besides tracks and a system of receiver(s), processor (preferably based on microprocessor) and a system of long range transmitters (range is of the order of 2 to 4 kilometers). This system takes care of special conditions like multiple tracks, junction points etc. The protection is based on sending warning signals to both trains under danger of collision. The proposed system is to be used in addition to the prevailing signaling system.
Objective/ Background of invention
Trains traveling on same Track in opposite directions (or in same direction under certain circumstances) will collide if normal signaling system fails. This invention is a method based on wireless communication. A method is proposed to avoid head on collision. Also a method is proposed to avoid collision of trains moving in same directions (or collision between one moving train and a stationary train).
Description of drawings
Figl shows Arial view or plan view of two track system, location of short range transmitter pairs, typical designation of pairs and some dimensions.
Fig la shows typical positioning of receiver and transmitter on engine, fields & range of short range transmitters and the minimum distance between transmitters in a pair.
Fig 2 shows arrangement of short range transmitters besides tracks at track changeover locations.
Fig 3 shows arrangement of special short range transmitters at the ends of multiple track locations.
Fig 4 shows arrangement of special short range transmitters at the ends of junction points.
Fig 5 shows some dimensions.
Fig 6 shows a typical alternative location of receiver on engine for receiving signal from
short range transmitters that are located besides tracks. . LjUfh s^
Description of proposed new system (refer fig 1)
Each track is provided with pairs of short range (say max 2.0mt.range) transmitters. For up track these pairs are positioned on to left side of intended direction of travel (form A towards C). For down track these pairs are positioned on to the left side of intended direction of travel (from C towards A). The distance "d" between the transmitters in a pair is kept more than maximum range of either of the transmitters, which ever is higher. The transmitters are designated by (al, a2), (bl,b2) (cl5c2) etc for up track pairs and by (a3,a2) (b3,b4) (c35c4) etc at locations A,B,C.etc. The relative positions are such that a2 lies ahead of al w.r.t normal direction of travel on up track and a4 lies ahead of a3 w.r.t normal direction of travel on down track. All transmitters are kept at a height of engine top surface or at a small height matching with height of installation of receiver on engines of all trains.
The transmitters al, bl, cl etc. emit a short range signal containing a code called SI (The code can be a signal of certain frequency or a digital / binary code or any other type of signal that can be detected uniquely by suitable and compatible receivers on the train engines.).The transmitters a2, b2, c3 etc. emit a short range signal containing a code called S2, Thus all pairs in the left of up track emit a short range signals containing SI andS2.
Similarly, the transmitters a3, b3, c3,etc. emit a short range signal containing a code called S3 and transmitters a4, b4, c4,etc. emit a signal a short range containing a code called S4.
Let us assume that a train travels on up track. A receiver is placed on the top of engine. When the train receiver first comes into the field of al of a pair it registers SI signal (with unique identification) in the memory of a processor on board engine and as soon as it enters the field of a2 and receives S2 signal it stores it in the processor. The information is processed and a long range (range is of the order of 2 to 4 kilometers) transmitter fitted on train emits a signal U. It keeps on emitting this signal till command is received from processor to alter it or stop it. If train happens to travel in opposite direction on up track, then the receiver on engine receives S2 signal first and then SI signal is received. Such a situation is processed by processor and a signal V is transmitted by transmitter on the engine. Similarly if a train travels in normal direction on down track, then receiver first receives S3 signal then S4. Upon processing this situation a signal X is transmitted by engine transmitter. If a train travels in opposite direction on down track, then receiver first receives S4 signal then S3. Upon processing this situation a signal Y is transmitted by engine transmitter. The above can be explained in following
* In this case the ranges of short range signals are to be properly set.
Once a pair of signals is received and the information is processed by processor to give a command to transmitter to emit a signal of particular kind as described in table-1, the processor erases the data of received from the pair of transmitters or sends it to a data base. Once it encounters signal from two short range transmitters of another pair the processor decides again about the kind of signal to be transmitted (new decision) and stops the previous signal for a short duration and activate the transmitter on the engine to retransmit as per new decision continuously till another fresh command is received from processor on board the engine.
Now if the receiver on the engine (which may be the same receiver as described
before for receiving signals from pairs of short range transmitters or a special receiver
compatible to signals emitted by transmitters on the engines) traveling in normal
direction on up track receives a signal V then a warning signal (warning 1) is received by
engine driver and even automatic braking can be done using this situation. If it receives
signals X or Y, it neglects the signals. If it receives a V signal then it gives a warning
signal (warning 2) to driver indicating that another train is approaching it or this train is
approaching another train on the same track. The processor on-board always performs a
comparison and gives a decision as per following table. . i . I
1. Upon entering another track (see Fig 2)
Two pairs of short range transmitters are located as shown so that whenever there is change of track the signal emitted by train changes accordingly immediately.
2. Multiple tracks(see Fig 3)
When train enters a multi- track e.g near a Railway Station, short range transmitters are placed as shown in Fig 3. The signal SA is received first for a train in up track at location "M". This will keep signal emitted in status quo. As soon as it receives SDA it de-activates emitting signal. No signal will be transmitted by transmitter mounted on the engine. Upon crossing station again it enters one of the tracks and first receives SDA and keeps the emitter in status quo i.e in off condition. As soon as it gets signal SA then it activates signal emitter and processor is ready to take signals and process information as per table-1 and Table-2. In essence the system proposed is not active when multiple tracks (more than two) are there. However separate signals similar to that
described for two tracks can be arranged to keep the system active in multi track portions also. In the absence of that normal signaling system in operation at present is relied upon.
3. T-Points and junctions, (see Fig 4)
Tracks from different routes often meet at a point called junction. In that event an arrangement as shown in fig.4 is made. The functioning is similar to that described above for multiple tracks. Here some special signals can be put to indicate driver that a junction is being approached. The normal signaling system shall be made use of at these instances.
Description of range requirements of transmitters/Receivers
1. The transmitters S1,S2, S3 ,S4, SA and'SDA are short range transmitters. The range is
such that Range is less than [Lmax +G+(Wmin/2) (see fig 5) and is more than [Lmax+ (G/2) ]
Where, Wmin is the minimum gap between tracks G is the width of tracks
Lmax maximum distance of installation of transmitters (namely SI, S2, S3, S4, SA, SDA) from outer rail of a track
2. The distance between transmitters in a pair (see fig.l) is little more than 2x(Range of short range transmitters).
3. The distance between two pairs of transmitters is based on the minimum distance or gap required to avoid collision when trains move in opposite directions at their maximum speeds on same track (in this case drivers receive an alert / warning signal). This distance shall be approximately 75% of this minimum distance required.
4. The range of transmitters on engine shall be more than or nearly two times the distance between pairs. Under above situation the trains will get a warning signal, when they are at 1.5 times the minimum safe distance for applying brakes.
5. The position of the receives for receiving short range signals from SI, S2, S3, S4, etc. shall be at top of engine or at the middle point of front portion at bottom (see Fig 6). Receiver for long range signals shall be same or different one and shall be suitably located.
6. The frequencies of operation, especially for long range transmitters on engine, shall be
such that minimum scattering, loss of signal due to reflection etc. occur. The position of
transmitters shall be judiciously chosen (preferably at engine top.) » IAAM) ^^
A major precaution to be taken
The processor has to be put in active mode or initialized before engine approaches a pair of short range transmitters i.e outside the range of a transmitter pair. It should never be started from a situation where in the receiver of engine is in between two short range transmitters of a pair. In situations where train has to back up from a location in between two short range transmitters driver shall reactivate or initialize the processor once the engine comes out of range of pair of short range transmitters.
Summary of invention
This invention is about an anti-collision system for railways based on wireless communication. The invention is based on sending warning signals transmitted form engines of trains. These signals are sent from engines upon receiving commands from onboard processors which process information received from short range transmitters pairs located besides tracks. The processing of information by processor is carried out as per program made in accordance with logics indicated in table-1&2. Special short range transmitter pairs are placed besides tracks in the event of train approaching a multiple track location or a junction so that the system is deactivated and once the train leaves these locations, the system is reactivated. The proposed system is not a replacement for existing signaling system. It is to be used in addition to existing signaling system. The positioning of pairs of short range transmitters, distance between pairs of transmitters, distance between two transmitters of a given pair etc. are based on non interference of short range signals, safe gap requirement for application of brakes in the event of possible collision etc. The frequencies or types of signals chosen should be such that there is no misinterpretation or interference with other normal surrounding signals. The signals must be distinct. The system shall be initialized when receiver of engine is outside the range of any transmitter pair and not when receiver is in between two transmitters of a given pair.
Claims of Invention
I Claim an "anti-collision system for railways" as my invention having following features.
1. A system consisting of pairs of short range transmitters with different signals emitting continuously and are being placed on to left side or outer side of both tracks such that the pair of signals emitted by up-track are different from pair of signals emitted by down-track; the signals emitted by each transmitter in a track are also different as said above.
2. The said pairs being located at a distance apart in the same sequence such that the distance is about 75% of safe minimum distance required for applying brakes by drivers of oppositely traveling trains on the same track and said pairs are located at a distance from track such that the signal reaches the midpoint of width of train; the distance between two transmitters in a pair being little more than two times range of the said short range transmitters.
3. On the engine of each train at middle portion of lateral dimension i.e width, a receiver is located, on the same engine a processor which identifies the signals received and processes the information to send long range signals of particular predetermined type from transmitters located at suitable location, preferably at engine top. The signals emitted by engines are as described in Table 2 of description of system and are such that potential danger is warned and warning signal is received by each train driver so that brakes can be applied by both trains or automatic application of brakes can be done using this warning signal.
4. under special circumstances such as when multiple tracks are encountered (e.g when a station or yard is approached) and when a junction point of two different routes is approached a pair of transmitters of short range signals are provides besides tracks for deactivating and activating the said transmitter or engine as described in description and as shown in fig.3 and fig4.
5. the method of initialization of proposed system outside the range of transmitter pair.
6. The whole arrangement of devices logic of receiving signals and processing and
sending signals are as explained in table-1, table-2, fig 1, fig 2, fig 3, fig 4, fig 5, and
|Indian Patent Application Number||631/CHE/2007|
|PG Journal Number||28/2011|
|Date of Filing||28-Mar-2007|
|Name of Patentee||CH. RABI KUMAR|
|Applicant Address||43, TYPE-3 CPRI COLONY, NEW BEL ROAD, BANGALORE - 560012|
|PCT International Classification Number||B61L23/04|
|PCT International Application Number||N/A|
|PCT International Filing date|