Bombardier Unveils First Contactless Tram

In a bid to improve energy use and create a more aesthetically pleasing railway, Bombardier has introduced its first completely contactless and catenary-free operating tram. The new train, which uses a contactless power supply and no overhead power lines, incorporates Bombardier's PRIMOVE inductive power transfer technology as well as the integrated MITRAC Energy Saver, which provides cost reductions by recharging energy. Director of advanced technology development at Bombardier, Dr Carsten Struve, said that unique technology used in the tram would provide energy savings and eradicate ugly overhead power lines. "The catenary-free operation offers an entirely new prospect, particularly for trams operating in historic city centres where impressive cityscapes can now exist unencumbered by visual pollution from overhead lines," Struve said. "Combined with the new Bombardier MITRAC Energy Saver technology, the PRIMOVE system can also save additional energy." The PRIMOVE technology system uses principles found in transformer technology with electric power components hidden under the vehicle and beneath the tracks to produce energy for the tram's operation. This makes the system easier to install, eliminates the effect of weather conditions, reduces wear on component parts, and allows the tram to operate with lower noise levels and fewer emissions. The vehicle is equipped with pick-up coils underneath the vehicle, which are connected to the tram's traction system through a cable. The vehicle is only energised when the connected ground segments are fully covered by the vehicle, ensuring safe operation in areas such as pedestrian zones.  The MITRAC energy saver uses a pair of innovative capacitors, which store the energy released each time the vehicle brakes and reuse it during acceleration or operation. The system, which attaches to the tram's roof, been proven to save up to 30% of energy, reducing emissions as well as costs. The PRIMOVE technology system is part of the BOMBARDIER ECO4 portfolio of technologies launched by the company last year.

Challenges in using Wireless Sensor Networks in Railway Signalling

The use of Wireless Sensor Networks in a safety critical Domain like Railways signalling poses challenges in implementation and Operation. Some of the issues and challenges are discussed in this chapter.

 

1. Sensor network communications must prevent disclosure and undetected modification of exchanged messages. Due to the fact that individual sensor nodes are anonymous and that communication among sensors is via wireless links, sensor networks are highly vulnerable to security attacks.

 

2. The gateway nodes are prone to failures just like any sensor node, and they consume significantly more energy since they transmit over longer distances compared with sensor-to-sensor links. Failure of a Gateway node results to catastrophic results because, there not information regarding the yard status to the base station

 

3. Sensor nodes have limited computing power and memory sizes. This restricts the amount of intermediate result a node can hold, also the type of data processing algorithm on a Sensor node.

 

4. Signals detected at physical sensors might have errors. Malfunction sensors might repeatedly generate false signals, also there could be bias caused by the placement of the sensor.

 

5. Sensor Nodes, Driver Node and Gate Way node have to work in High EMI Environment. Since sensor networks can be deployed in different situations, wireless medium can be greatly affected by noisy environments, and thus the signal attenuates in regard to the noise. Note that an adversary can intentionally interfere and cause enough noise to affect the communication. It is vital to ensure that communication is on time to respond to emergencies.

 

6. Wireless sensor networks at times may add delay in sending data to the base station due to the routing algorithms, etc, but Railway Signalling is very time critical job, any delay in receiving the data leads to Catastrophic results.

 

7. If a sensor node fails due to a technical problem or consumption of its battery, the rest of the network must continue its operation without a problem. Researchers must design adaptable protocols so that new links are established in case of node failure or link congestion. Furthermore, appropriate mechanisms should be designed to update topology information immediately after the environment changes so as to minimize unnecessary power consumption. 

 

8. The network should be scalable and flexible to the enlargement of the network's size. The communication protocols must be designed in such a way that deploying more nodes in the network does not affect routing and clustering. Rather, the protocols must be adapted to the new topology and behave as expected. In other words, the network must preserve its stability. Furthermore, introducing more nodes into the network means that additional communication messages will be exchanged, so that these nodes are integrated into the existing network. This must be done in a way that a minimum number of messages need to be exchanged among the sensor nodes, and thus battery is not wasted unreasonably.

 

9. As in Wireless Sensor Networks Both Ground based signalling (Way Side Signalling) and On-Board Signalling (Cab Signalling) get merged, so there is the complexity of linking the ground based control laws to the inputs received from the On-Board Sensors in the train

 

10. Design and development of failsafe, fault tolerant and energy saving  network routing algorithms is a complex design

 

State Machine Basics