Connecting radios all over the world

MVP - Background

Challenge

After nearly 20 years of service it was time to change out the Motorola SmartZone system in the Stockholm Metro trains for a new Tetra system.

Since the buses in Stockholm already used a Tetra system it was decided that the two systems should be made into one. In this way good coverage and good redundancy would be possible.

The trains used a tailor made panel with thumbwheel switches to set line, destination etc. This panel also set the talk group on the SmartZone radio depending on the line information.

New operator panel

The trains needed a new panel with the same functionality towards the train, plus communication with the new Tetra radio.

The size of the panel and many of the connections were therefore given before hand.

Since the weakest part of the old panel had been the thumbwheels, we did not want to build it like that again. But at the same time build something that was intuitive for the driver to learn. It should look and feel like the old panel.

Engineered in 1992…

…reengineered in 2012

Learning curve

With the new panel that uses a touch screen to build virtual thumbwheels, the learning curve for the drivers was minimal. They could all handle the new radio system after a few minutes.

Functions

The driver still sets the line and destination on the panel and the panel then sets the talk group on the Tetra radio and the signs on the train, just like before.

Apart from that, there are new functions like text messaging and passenger PA announcements from the dispatcher.

There are also help texts on the display that makes it much easier for new drivers to set line etc in the right way.

Modern train in the Stockholm Metro

Old train in the Stockholm Metro

Back to Top