Bode Digital Railways – The Boarding Management Unit

In order to face the challenges of the increasing speed of technological developments in the 21st century, Schaltbau Bode has introduced an innovative digital strategy to improve both safety and passenger comfort with their own Boarding Management Unit.

A Bode entrance system will no longer rely on the classic order-action principles only, but rather monitoring the whole entrance area and e.g. replacing the pushbutton logic with an innovative gesture controlled interface. Complex sensor systems already successfully established and well accepted in the automotive and industrial sector will now be an integral part of a door system allowing operation by virtual interfaces and offering even more safety and comfort. Even passenger counting and ticketing are side features especially interesting for any public transport operators.


The implemented sensor arrangement of the entrance system relies on highly sophisticated linear laser scanning devices. The laser distance sensor, currently one of the most powerful measurement tools on the market, is used in a variety of industrial applications such as driving assistance systems, medicine technology, robotics etc. Due to its reliable characteristics, e.g. accuracy, definiteness, interference immunity, and target independence it is more than state of the art technology used within the heart of the BMU.

The grouping of numerous laser beams into one central sensor unit allows comprehensive monitoring with a great many functional features. Moreover, this kind of sensor is not subject to any data protection limitations, which is a clear advantage in comparison with CCTV (closed-circuit television) based systems. Thus, the Bode BMU is solely based on sensors using the laser technology.

The BMU arrangement usually is built around two laser sensors, i.e. an internal sensor and an external sensor. Each sensor is installed in such a position, that the sensitive areas for interaction with the Bode entrance system can be monitored. The external sensor is located outside, preferably above the door. The monitored area is visualized as the top perspective view over the scenery as illustrated in Fig.1. The internal sensor is located either on the top right or left side of the entrance in order to cause no interference with the mechanics of the door but still maintain a comprehensive overview of the vestibule entrance area. The covered areas of both sensors are called the internal active area and the external active area. The information of both active areas can be directly provided by the laser sensors and evaluated by the door control unit, respectively.


FIGURE 1: Sensor positions and Bode Boarding Management Unit

Replacing and enhancing existing functionalities

A large variety of different sensor types is currently used in entrance systems. The most popular and widely known sensors and switches are

  • Push buttons
  • Light curtains and light barriers to monitor the passenger flow
  • Switches and sensitive pressure mats integrated in step systems to prevent any step movement while people are boarding
  • Sensitive edges to detect obstacles and prevent passengers from being trapped in closing doors
  • Ultrasonic sensors to measure the extension distance of steps to the platform

In order to connect these various sensors to the door control system, it is necessary to implement an elaborate system of electrical interfaces. This does not only require significant engineering effort and thus cost, it does also have a considerable impact on reliability and durability due to the number of different electrical interfaces.

The new Bode BMU sensor system based on laser range measuring technology is able to replace all of above mentioned switches and sensors and thus to reduce the number of components. The overall reliability of the system is increased while lifecycle cost (e.g. planning, maintenance, etc.) are minimized. Even though the overall sensor system is simplified, an enhanced perception of the entrance’s environment is achieved. This originates from the higher information flow and output of the newly employed technology. The capabilities to react to its different surrounding conditions are augmented.

The door system will now be able to detect and react to obstacles without any contact, reducing or even avoiding possible incidents that may result from the door’s kinetic energy while opening and closing. The new capability to accept e.g. door open commands also increases passengers’ convenience. The ‘touchless’ user interface can be enhanced to a gesture controlled interface enabling the passenger to request special functions provided by the door or the vehicle such as control a built in infotainment system.

Further, the new Bode sensors are capable to identify potential sources of hazard and thus trigger a warning to passengers even before an actual danger occurs. This functionality may decrease the operating cost for operators as the passengers can be directly guided to leave for example danger zones or to leave highly frequented areas and hence increase the efficiency and comfort of the over-all service.

Just recently, the close-to-production prototypes are going through an extensive validation with the support and cooperation of two well-known urban transport operators located in Kassel and Berlin, Germany.

With this approach of prototype validation in an operating environment, it is expected to gain further experience regarding the functional stability and algorithmic setup of the sensor system. Further these installations are being used to investigate the general acceptance of passengers of the new interface and finally explore the multitude of further potential applications in the future.


FIGURE 2: Object and Person recognition using the Bode sensor framework

Going beyond

The introduction of the Bode Boarding Management Unit does not only reduce the number of electrical interfaces within a door system by replacing the classic actuators such as pushbuttons, sensitive edges or infrared sensors but opens the door to a whole variety of new functionalities. These functionalities are apt to improve the traveling experience of passengers as well as to provide a supplier of transportation more detailed information about their services and increasing efficiency and convenience.

The two sensors that are mounted as part of the door system itself are able to monitor events that are occurring in the vicinity of the inside and outside entrance area capturing movements and passenger flow. The basis for all such considerations is a suitable object recognition that assigns categories to the patterns that appear at a time in the laser scanner. Aforesaid categories are humans, objects, humans with objects, etc. The sensor system also retains the timings of the events that are detected in the course of an episode.

These data and the two perspectives (see Fig. 2), that are delivered with the system, allow to establish a number of assumptions about the events that are occurring around a BODE door. By matching patterns of persons in the internal and the external sensors and taking into account the respective timings, it can be deducted whether a person is entering or exiting the vehicle through the BODE door. Thus, a passenger counting system can be deployed with minimized costs, simply by using the technical features of the BMU. Furthermore, it is possible to detect passengers with reduced mobility (PRM) (e.g. wheelchair users) and appropriate measures can be executed accordingly (for example an extended wheelchair ramp).

These are only a few examples of the technical abilities such a Boarding Management Unit may bring into the Passenger Transport.