Nissan Plant Tows the Line Autonomously

Nissan Motor Co.’s assembly plant in Oppama, Japan, is using modified Leaf electric cars to autonomously tow other vehicles from the end of the production line to shipping docks.

The carmaker, which has been testing the system for about a year, says it has completed more than 1,600 trial runs at Oppama. Other Nissan facilities in Japan and elsewhere are evaluating the system too.

Unlike automatic-guided vehicles for transporting parts, the self-driving Leaf doesn’t require rails, magnetic tape or other special infrastructure to operate, Nissan notes. Towed vehicles ride on a train of trollies behind the driverless lead vehicle.

The towing car is equipped with an array of cameras and lasers that detect lane markings, curbs and potential obstacles. The information is combined with digital maps to determine a vehicle’s location and surroundings.

All of the plant’s driverless Leafs are connected to a central traffic control system, which monitors their location, driving speed, remaining battery capacity and operational status. If two of the automated towing cars meet at an intersection, the control system’s algorithm determines which one has the right-of-way.

Nissan says fail-safe systems are used to counter potential risks and unexpected conditions the cars may face during autonomous driving, including adverse weather and low-light conditions. Towing routes also can be altered to accommodate changes in production processes.

The automated Leafs are guided by an expanded version of the ProPilot system Nissan launched earlier this year on the Serena minivan in Japan. ProPilot enables the van to drive automatically within its own lane at speeds as great as 62 mph.