Cargoo: Interaction design for a double-decker car-carrier wagon

Peter walks to the first wagon of the train, which is almost 650m long. He lifts the lid of the operator’s panel and pushes the button that opens the wagon roof. He now has to keep the button pressed for two minutes until the roof opens fully. But because Peter and his fellow-workers are being paid piecework, he does not want to waste valuable time waiting. He locks the button in place by pushing a toothpick into the narrow gap between the button and the panel, and then walks to the next wagon. He does the same at every wagon.

The procedure would certainly not meet with the approval of the safety officer, and is one of the many things that this interaction design project is designed to improve.

Our client was developing the next version of their closed double-decker car-carrier wagon and also wanted to enhance the operation of the wagon.

We started with user research – visited a loading bay, interviewed the jockeys (the people who drive the cars onto the wagon) and their managers, observed a loading session and figured out how the jockeys got the job done. We were surprised to discover that the design of the control panels actually made the jockeys’ job of loading all of these high-value cars onto the car wagons more difficult. For example, the jockeys received no feedback as to the position of the platform and the gauges they relied on were all positioned at different heights and used different scales.

The goal of the project was to improve the process to load the train as quickly and as safely as possible. To determine the ideal loading procedure, we therefore simulated a number of different loading scenarios. Based on the findings and the user research we built first low fidelity prototypes (e.g. with pens and washers) of the control panel. Later on we developed a full-scale prototype to test the positioning of the control panels and gauges. The details, such as positioning of the control panel, or positioning of the buttons in the control panels were refined over many iterations and in close collaboration with the railway specialists who designed and built the wagon itself. Not unexpectedly, we had to make some changes to the interaction design for technical reasons, but we worked closely with the engineers to maximise the effectiveness of the design.

Applying interaction design to a product outside of the “usual digital context” was a great experience: From user research in an environment new to us, over designing the many details, to finding a common language and understanding among the different disciplines involved.

More details and pictures of this case study can be found at:

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