GB2049250A - Controlling the movement of objects, such as vehicles, along a common path or track - Google Patents

Abstract

In the automatic travelling control of objects such as vehicles (1, 2 and 3) moving along a common path or track (4), control signals are transmitted in a direction contrary to the direction of motion, in a transmission medium (4) extending linearly along the path or track. These signals are received 8 by each vehicle (1, 2, 3...), and their further transmission is passively suppressed 10. 0n each vehicle the received signal is regenerated, and transmitted 9 to the following vehicle (2, 3). The speed of a following vehicle (2, 3,) is controlled by the regenerated signal from the object (1, 2) directly in front thereof and in the event of breakdown of a vehicle the regeneration process is stopped and in the absence of a received signal the following vehicles are automatically braked to a halt. <IMAGE>

Description

SPECIFICATION Method of and arrangement for controlling and/or braking the movement of objects, such as vehicles, along a common path or track This invention relates to a method of, and an arrangement for controlling and braking automatically the movement of objects, such as vehicles, along a common path or track, so as to ensure safe spacing of said objects, using signals which are transmitted and received by the objects, in which the speed of each following object is in each case controlled by the object which is disposed directly in front thereof.

In order to meet increased demands in passenger conveying capacity and high travelling speeds, in relation to modern track-tied public transport systems, (e.g. in so-called "cabin taxi systems") it is necessary to increase the occupancy density of the individual route sections. As a consequence the safetyspacing of the individual vehicles becomes correspondingly more important.

For this purpose, there has been increasing development of so-called linear influencing systems which, in addition to contributing to safety by continuous speed monitoring, perform automatic braking and travelling control of the individual vehicles. Signals determining the magnitude of the permissible maximum speed are transmitted as travelling commands between the track section and the vehicle, and the corresponding speed for the section lying ahead is also indicated. The appropriate mechanisms for providing the travelling commands are disposed so as to be centralised at points at which information is available for a relatively large overall region.If, however, the permissible distances between the individual vehicles are to be shortened, each vehicle must, substantially independently of specific reference points of the section, itself regulate its speed and its distance relative to a vehicle which is up ahead. For this purpose, United States Patent No. 27 02 342 proposes an arrangement for the safe spacing of trains in which, in the following train a speed-dependent voltage is compared with a signal which determines the distance from the train up ahead. This signal is sent out by the following train, is reflected by the train in front and eventually received once again by the following train (reflection method). In this way a sigral change which is dependent upon the distance between the two trains is obtained.

In this known arrangement, furthermore, in the following train a warning signal is generated and possibly braking is initiated whenever the distance necessary for braking of the following train, according to the speed at which it is travelling, is not present between it and the train in front.

Furthermore, known from German Auslegeschrift No. 21 14 621 is a method of and an arrangement for automatic safe-distance braking and travelling control, in which respect the object (vehicle) ahead sends out a signal the message content of which changes with the speed of this emitting object (vehicle), and the following vehicle receives this signal as a function of a suitable speed. At standstill, the intensity of the signal of the emitting object (vehicle) reaches a maximum; at maximum speed the signal intensity is a minimum. In this method, therefore, it is necessary for the sensitivity of the receiving devices in the vehicles to be at a maximum when travelling at the highest speed.

In the case of automatic track-guided passenger traffic having a very close train spacing and operating at high speed, to avoid accidents it is absolutely necessary to be able to recognise defective vehicles on the roadway promptly in order to achieve rapid braking and thereby avoid a collision. All of the previously-known methods and arrangements for effecting automatic safe-distance braking and travelling control are, because of their high susceptibilities to breakdown, not suitable for the rapid and intrinsically safe recognition of defective vehicles.Methods in which a signal which changes with the speed of a vehicle and the message content of which is evaluated (possibly only after multiple reflection between two consecutive vehicles) by the subsequent vehicle are susceptible to trouble and therefore cannot prevent collisions where short vehicle spacings and high operating speeds sufficiently reliably and safely.

The problem underlying the invention is to develop a method of and an appropriate arrangement for controlling and/or braking the movement of objects, such as vehicles, along a common path or track in such a way that, in the case of track-tied vehicles having a very close spacing and operating at high speed, a vehicle which is in the path is recognised in a simple manner promptly with high reliability and safety, and effective rapid braking is initiated.

In accordance with the invention, this problem is solved, in relation to the method, in that there are transmitted, in a transmission medium which extends linearly along the path or track, contrary to the direction of movement of the vehicles, signals which are received by each object (vehicle), which are passively suppressed and which, actively regenerated, are passed on to the following object (vehicle), and in that at the same time the speed of the following object (vehicle) is controlled by the actively-regenerated signal of the object (vehicle) which is disposed directly in front thereof.

Advantageous developments of the method of the invention are defined in claims 2, 3 and 4 appended hereto.

Thus, in the method of the invention, in the absence of a signal, irrespective of the speed and the spacing of the vehicles, rapid braking of all of the subsequent vehicles is brought about. A further safety feature arises additionally in that also in the event of failure of the signal transmitter in a vehicle at once rapid braking of all the following vehicles is effected. Additionally, locality information can be transmitted which information, in conjunction with the respective locality information of the following vehicle, serves to determine spacing measurement and to control the speed of the latter.

In accordance with the invention, the described problem is solved, insofar as the arrangement or apparatus is concerned, in that each object (vehicle) has, at its end pointing in the direction of movement, a receiver which is coupled to the transmission medium, in that furthermore each object (vehicle) carries, at it other side, a transmitter which is coupled up to the transmission medium, and in that, arranged between the two coupling points, is a passive signal flow suppressor which can be coupled into the transmission medium and which is connected securely to the object (vehicle).

In accordance with a further advantageous development, the transmission medium is designed as a slotted wave guide, the coupling up of the transmitter and the receiver being effected by coupling probes which project into the slotted wave guide. The signal flow suppressor which is arranged between the two coupling points conveniently comprises a plate which plunges into the slotted wave guide and which is preferably constructed from materials which have a high damping in the operating frequency region of the slotted wave guide.

The design of the transmission medium as a slotted wave guide ensures reliable disturbance-free transmission simultaneous with good transmission quality of the signals.

Moreover, only negligibly small radiation penetrates outwardly.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic side view illustrating three vehicles arranged one behind the other on a common path or track and forming part of an arrangement according to the invention; Figure 2 is a schematic cross-section through one of the vehicles of Fig. 1 and through a slotted wave guide arranged therebelow; Figure -3 is a schematic longitudinal section (taken in the direction of travel) through one of the vehicles and the wave guide arranged therebelow.

The arrangement illustrated comprises vehicles 1, 2, 3 constituting individual passenger conveyances (e.g. so-called cabin-taxis) of a short-haul traffic system, in which each vehi cle is intended to ply predominantly without stopping automatically between a departure point and a destination. If these vehicles 1, 2, 3 as well as further ones (not shown) ply over the same path in each case with precisely the same speed, collision would be impossible.

The spacing between the individual vehicles could then be selected to be very small; for example smaller than the absolute braking distance. As a rule, however, the equal speeds cannot be maintained with all of the vehicles, and of course a vehicle which has broken down can block the path. Therefore, each of the vehicles 1, 2, 3... must have available a rapidly-effective, automatic braking and travel ling control.

As is evident from Fig. 1, each of the vehicles 1, 2, 3... has, at its end pointing in the direction of movement 5, a respective receiver 6 which is coupled up at a coupling point 8 by way of a coupling probe 11 to transmission medium 4 which extends along the path of movement of the vehicles. Simi larly by way of a coupling probe 12, at the coupling point 9 at the opposite end of the vehicle, a transmitter 7 is coupled up to the transmission medium 4. Disposed between the two coupling points 8, 9 is a passive signal flow suppressor 10 which can be cou pled into the transmission medium 4 and which is connected securely to the respective vehicle 1, 2 or 3.

What has proved to be an advantageous design for the transmission medium 4 is a slotted wave guide as is shown in Fig. 2 in a cross-section taken perpendicularly to the di rection of movement of the vehicles. Prefera bly a slotted wave guide having a rectangular or trapezoidal cross-section is used.

However, as an alternative, a slotted wave guide, having an elliptical or circular cross section, can be used. In the exemplified em bodiment, the coupling probes 11 and 1 2 which are connected to the receiver 6 or the transmitter 7 plunge, from above, into this slotted wave guide 4. Lateral projection or projection from below, for protection of the slotted wave guide 4 against entry of rain water and dirt, would also be possible. The signal flow suppressor, which can plunge into the slotted wave guide consists, in the exem plified embodiment, of a plate which is prefer ably constructed from materials which have a high damping capacity in the operating fre quency range of the slotted wave guide.

Fig. 3 shows, in schematic representation, a longitudinal section (in the direction of travel) through one of the vehicles 1, 2 or 3. It can be seen from this section that the two cou pling probes 11, 1 2 are designed as loop antennae and are coupled into the electromag netic field of the slotted wave guide 4. Extending therebetween is the signal flow sup pressor 10, in the shape of a rectangular plate the length of which is approximately equal to twice to three times the length of the operating wavelength of the slotted wave guide 4.

The arrangement, in accordance with the invention, for the automatic safe-distance braking and travelling control functions as follows: In the undisturbed operating state, in the transmission medium 4 which extends linearly along the path, signals are transmitted contrary to the direction of motion, which signals are suppressed by each vehicle 1, 2, 3 and so forth, by way of their coupling probes 11 and receivers 6 passively with the aid of the signal flow suppressor 10 and are passed on, actively regenerated, by way of the transmitters 7 and coupling probes 1 2 to the following vehicle, for example vehicle 2. In this respect, the speed of the following vehicle is controlled by the actively-regenerated signal of the vehicle which is disposed directly in front thereof.

So that the signal transmission to the following vehicle is effected only by way of transmitter 7 and the coupling probe 12, and not also directly through the transmission medium 4, a signal flow suppressor 10 plunges into the transmission medium 4 between the two coupling points 8, 9. In the illustrated exemplified embodiment, a rectangular plate plunges, at the location of the maximum electrical field strength, into a slotted hollow conductor. If it is a question of a plate made from conductive material, it brings about a shortcircuit; if an absorbing material is used, absorption of the electrical field lines is effected.

If a vehicle, for example vehicle 1, comes to a stop as a result of a technical defect or is stopped for some other reason it no longer sends out a respective actively-regenerated signal to the following vehicle, for example vehicle 2. As a result this following vehicle is automatically stopped by rapid braking. The rapidly-braked vehicle similarly no longer sends out an actively-regenerated signal, so that a kind of chain reaction is triggered off.

All of the vehicles 2, 3 and so forth which are following the defective vehicle, for example the vehicle 1, are successively rapidly braked.

When the trouble has been obviated and the vehicle which came to a halt has again got moying, it sends an actively-regenerated signal to the following vehicle, whereby, in the manner of a chain reaction, all of the following vehicles start up once more. If the actively-regenerated signal is, in each case, additior ally provided with locality information about the emitting vehicle, then, in conjunction with the respective locality information of the following vehicles, spacing (or distance) measurements can be undertaken, which can be utilised to control the speeds of the individual vehicles. In the case of this design, the positive high-speed braking can remain restricted to the vehicle following the defective vehicle, since the remaining following vehicles can be halted over normal distances.

The method in accordance with the invention, and the practical arrangement, for the automatic safe-distance braking and travelling control of objects which are on the same path or track is suitable not only particularly well for automatic crack-guided passenger traffic, but can also advantageously be used in the case of machine tools, conveying plants and so forth.

Claims (8)

1. A method of automatically controlling and/or braking the movement of objects, such as vehicles, along a common path or track so as to ensure safe spacing of the objects (vehicles) using signals which are sent and received by the objects, in which the speed of each following object is controlled by the respective object which is present directly in front thereof, characterised in that there are transmitted, in a transmission medium which extends linearly long the path or track, contrary to the direction of motion of the vehicles, signals which are received by each object (vehicle), which are passively suppressed and which, actively regenerated, are passed on to the following object (vehicle) and in that at the same time the speed of the following object (vehicle) is controlled by the activelyregenerated signal of the object (vehicle) which is disposed directly in front thereof.

2. A method as claimed in claim 1, in which an object (vehicle) which has come to a halt, e.g. as a result of a technical defect or for other reason, does not pass on an activelyregenerated signal to the following object (vehicle).

3. A method as claimed in claim 2, in which, in the absence of an actively-regenerated signal, the following object (vehicle) is brought to a halt by rapid braking and, upon reinstatement of the same, continues its movement.

4. A method as claimed in claim 1, 2 or 3, characterised in that the actively-regenerated signal is provided with information concerning the location of the emitting object (vehicle) which, together with the locality information of the following object (vehicle), serves for measuring the distance (or spacing) and for controlling the speed of the latter.

5. A method of automatically controlling and/or braking the movement of objects, such as vehicles, along a common path or track substantially as hereinbefore described with reference to the accompanying drawings.

6. An arrangement for carrying out the method of any of claims 1 to 5, characterised in that each object (vehicle) has, at its end pointing in the direction of motion a receiver which is coupled to the transmission medium, in that furthermore each object (vehicle) carries, at its other end, a transmitter which is coupled to the transmission medium, and in that, arranged between the two coupling points, is a passive signal flow suppressor which can be coupled into the transmission medium, and which is connected securely to the object (vehicle).

7. An arrangement as claimed in claim 6, characterised in that the transmission medium is a slotted wave guide, in that coupling of the transmitter and the receiver is effected by coupling probes which project into the slotted wave guide, and in that the signal flow suppressor which is arranged between the two coupling points comprises a plate which plunges into the slotted wave guide and which is preferably constructed from materials which have a high damping in the operating frequency range of the- slotted wave guide.

8. An arrangement for carrying out the method of any of claims 1 to 5 and substantially as hereinbefore described with reference to the accompanying drawing.