PSItraffic Automating Six Bus Depots

Hamburger Hochbahn AG Introducing DMS

A city with over one million residents and millions of tourists needs public transport capable of meeting extraordinary requirements. It is unimaginable for an organization to be a leader in multiple technologies without outside IT support. And this must begin at the depots, for example with a modern Depot Management System (DMS). 

„Clean buses“ in Hamburg City

Since 1912, the Hamburger Hochbahn AG (HOCHBAHN) – founded the year before by Siemens & Halske and AEG – has operated the then recently constructed elevated rail. In 1965, HOCHBAHN was a founding member of the Hamburger Verkehrsverbund, the first transportation network in the world. Today, Hochbahn is wholly owned by the Free and Hanseatic City of Hamburg. It is the sole operator of the four subway lines and the majority of Hamburg's bus network. With over 4,500 employees, HOCHBAHN transports around 1.2 million passengers every day, making it the second-largest public transport company in Germany.

"The colleagues praise the system because it works so well and there are no vehicle shortages. Even at times with traffic congestion, the situation was significantly improved by the DMS. It is already evident that the decision for PSItraffic has paid off and that we are much closer to achieving our goals."

Dr. Heinrich Böse
Project Manager

XXL-Bus of the HOCHBAHN at the central bus station

The bus network has a length of over 920 kilometres, with 112 lines and over 1,300 stops. The approximately 800 vehicles include standard articulated, city and express buses, as well as the most modern diesel hybrid and fuel cell hybrid buses. These buses are at home in five depots, where they are refuelled, cleaned, maintained and prepared for their next deployment. This is the responsibility of the Hochbahn subsidiary FFG Fahrzeugwerkstätten Falkenried GmbH and the TEREG Gebäudedienste GmbH, of which Hochbahn is the majority shareholder.

Dr. Heinrich Böse, responsible for system planning and technology in the Bus Operations department of HOCHBAHN reports: „Until recently, dispatchers were required to create plans by hand for the smooth operation of the buses. That was not only time-consuming, but also error- prone.“ Routes and assigned vehicles were recorded by hand in schedule tables, including the scheduled departure of the bus and the driver, it's return time, and whether one driver will be relieved by another. To document this, all schedule tables had to be archived.

Tracking by hand and plug

Vehicle tracking in the depot was achieved using the Steca charging station system, which supplies compressed air and electricity, etc. Upon entering the depot, the bus driver would drive to the free parking position of his choice and attach the Steca system and an air hose to the bus.

At this time, the PC would register the bus. After a driver correctly connected his bus to a station, the dispatcher knew its exact location. „But that was also one of the problems with this system,“ acknowledges Böse. If a plug was not inserted correctly or did not work, the dispatcher received no information – which was also the case at the non-Steca-supplied parking positions. For this reason, employees performing nightly vehicle maintenance manually created a parking diagram recording where the vehicles were actually located.

Even though the resulting errors and greater effort were bearable, it was very difficult to implement other plans with these old methods. First and foremost, HOCHBAHN was seeking to improve economically and increase its competitiveness. „For example, a new refuelling strategy was required,“ explains Böse. Another primary strategic goal was becoming a leader in the development and testing of innovative drive technologies.

The new technologies were not to be used freely, but were instead restricted to specific routes. „But this is where the human factor reaches its limits. If I have nine or ten different vehicle types which need to be assigned to specific routes, I cannot come an hour earlier to figure out how to organize this,“ Böse points out.

Strategic goals for the future

Another major goal was process transparency and standardization. „Three partners are working together at the depots, including HOCHBAHN itself, FFG and TEREG. To ensure that all three are working from the same basis and know what is happening at the depot, we wanted to ensure transparency with a vehicle tracking system. We considered a depot management system as the ideal solution to implement our goals,“ says Böse of the decision. The company HanseCom, the responsible service provider for the entire DP operation, was commissioned as the general contractor to implement the system.

A tender for the system supplier was made based on the specifications created in 2009. In late 2010, the Berlin PSI Transcom GmbH received the order to supply, implement and commission their depot management system PSItraffic. „Money also certainly played a role in this decision. This offer was simply the most economical“, says Böse. However, he also stresses the flexibility of the Berlin company, who guaranteed a free choice of tracking system, for example.

Starting with 1000 pages

„We launched the project in the classical way,“ says Böse, „by creating a detailed specification with all of the steps we had defined.“ This specification grew to about 1000 pages. At the end of 2011, it was approved and the implementation phase began. To start, one depot (in Hummelsbüttel) and the control centre were equipped with the infrastructure for the new tracking system, computer hardware, and DMS software.

Buses had to be equipped with a roof antenna for the tracking system Symeo LPR (Local Positioning Radar), a radio frequency sensor for determining the distance and position of moving objects. Testing of the tracking system at the pilot project depot began in mid 2012. The step-bystep commissioning began in Hummelsbüttel in early 2013. At this point, they had also begun equipping the remaining depots with hardware, and all vehicles have now been equipped.

The DMS and several subsystems were integrated into the existing IT environment, for example, with the ITCS (Intermodal Transport Control System). All logins and logouts from routes are collected there, as are delays, position tracking en route, and disruptions and messages. These data are also transmitted to the DMS, along with re-registrations and mileage, together with the delay forecast when returning to the depot.

ITCS feeds the DMS

Before departure, the driver logs into the ETP (Electronic Ticket Printer). This system has an interface to the ITCS, which means that the login is sent from the on-board computer to the control computer and the control centre. While the driver travels his route, his position is tracked by the ITCS system.

Upon completion, he transmits his delay forecast to the DMS from his final stop. If the vehicle is reserved, this enables the garage to know, for example: he will arrive late, a different task can be done instead. Upon entering the depot, he receives a signal telling him where to park his vehicle.

At the beginning and the end of every trip, the DMS receives an update from the control computer, including the mileage, for example. If the driver notices a disturbance during his route, he sends a communication request to the control centre. There, he reports the type of disturbance.

In a separate system, the control centre then creates a fault report, which is sent directly to the ERP system in the garage, where it is also dealt with, thus circumventing the DMS. The control centre blocks the vehicle for further use with a fault report in the DMS. Thereafter, only the garage can release the vehicle in the DMS.

Targeted heating and refilling

Schedule and roster planning is done by the so-called performance planners. Using a separate IT system, they determine the vehicle routes and the driver duty schedule. The assignment of driver shifts is made using the personnel planning system, and vehicle dispositions are made via the so-called data market. The route data generated are stored in a central database.

All backend systems retrieve this data from here. The DMS queries schedule data once for the next seven days, and shift data every 15 minutes. In this way, the system can be updated daily, even in case of changes.

In the past, preheaters were required to manually preheat vehicles, or the Steca system activated the heaters on a strandby- strand basis. Today, the DMS automatically activates preheaters in the buses according to a predetermined algorithm based upon the outside temperature and the starting time of the route. This avoids unnecessary heating and pollution.

An additional goal was improving the cost-effectiveness through a new refuelling strategy. Here, a separate tank data system collects tank data from all vehicles, making them available to the DMS. Whereas previously vehicles were refuelled every day, regardless of their mileage, now an effort is made to only refuel buses when the fuel is not sufficient for the next disposition. „The DMS should plan so that we do not need to refuel during the day. Instead, it should decide in the evening which vehicle is refuelled and which is not,“ explains Böse.

Visible successes

The simultaneous introduction of a personnel disposition system and the DMB also lead to process changes. Vehicles are announced to the drivers on monitors 15 minutes before departure. This makes it possible to communicate changes on short notice. According to Böse, process transparency has already improved noticeably: „Everyone now has the same view of the depot. Everyone knows where the vehicles are parked and what condition they are in.“ This has drawn the three companies involved closer together. Böse adds: „The result so far is that we have not had any vehicle shortage in Hummelsbüttel.“

Time savings are also expected because the DMS automatically replaces many previously manual lists with automatic processes. After more depots have been added, a significant reduction in the vehicle reserve is planned through improved disposition. The faster disposition speaks for itself: attributes like requesting a disposition, requesting a parking position, driver and vehicle, as well as fuel and maintenance data are automatically accounted for by the DMS, which quickly handles the operations of an entire depot.


Dr. Thomas Langner
Head of Sales Public Transport