The demonstration took place Feb 25, 2013, at the North Site of AIST (Japan's National Institute of Advanced Industrial Science and Technology) Tsukuba Center in Tsukuba City, Ibaraki Prefecture. The latest development is a result of NEDO's five-year project, "Development of Energy-saving ITS Technologies," that started in fiscal 2008 with a budget of about ¥4.4 billion (approx US$47.7 million).
In September 2010, NEDO showed three large trucks running in formation at a speed of 80km/h with an inter-vehicle distance of 15m. This time, four trucks ran in formation at a speed of 80km/h with an inter-vehicle distance of 4m. With the shorter inter-vehicle distance, which contributes to reducing air resistance, it became possible to improve the fuel efficiency of each of the four trucks running in formation by 15% or more on average, NEDO said.
To drive the trucks in formation, NEDO equipped them with (1) a function to detect obstacles in front of them, (2) a function to recognize white lines, (3) an inter-vehicle communication function and (4) a unit to control trucks running in formation. All of those functions were realized by using duplexed systems, NEDO said.
Specifically, NEDO added (1) a milliwave radar and infrared laser radars for the obstacle detection function, (2) cameras and infrared laser radars for the white line recognition function and (3) a 5.8GHz wireless communication module and infrared communication module for the inter-vehicle communication function. For the control unit, two printed circuit boards (PCBs) were used, and a fail-safe function was added to monitor the calculation results of the two PCBs.
All of the four trucks had data on the oval course where they were tested. And the leading truck autonomously ran by using the obstacle detection function and the white line recognition function.
Each of the three trucks following the leading truck recognized a truck running in front of it with sensors. And they exchanged information such as the speed of the leading truck with the inter-vehicle communication function every 20ms.
To improve the accuracy of the white line recognition function, cameras and infrared laser radars were attached to the sides of the truck.