Automobiles are indispensable for our life. Recent key technologies are electric drive and autonomous driving. In addition, conventional technologies are also progressing. This special section provides articles that concern recent automobile technologies on control, autonomous driving, electric drive and the consideration of environment, driver assistance system, and crash simulators for the research and development of passive safety devices. At the beginning of this special section, kinds of automobiles and needs for automobiles are described, and some articles that concern simulation and optimization technologies for automobiles are introduced in this article.
Automotive control technology relates to everything that the ECU（Electronic Control Unit） controls, and the number of on-board ECUs reaches several tens. A hybrid car is a moving thermal power plant, a self-driving car is an autonomous robot, and a connected car is a moving personal IT space. Automobiles are composed of various control systems, and they are rapidly innovating. In this paper, by reviewing the transition of automobile control technology, the essence and future trend of them will be clarified.
In recent years, the word "Autonomous vehicle" has come to be heard in various scenes including television, newspaper and other media. Autonomous vehicles are thought to have various advantages such as improvement of safety of cars, improvement of comfort of passengers, elimination of shortage of public transportation system. In this paper, we describe the outline of the technology required for autonomous driving system. In addition, we will outline the public road experiment which the authors' university is carrying out as the first trial at domestic university.
Solar panels for vehicles can’t generate as much power for driving because of size limitation. Therefore, Toyota has developed a solar charging system for Prius PHV that can use solar energy for driving. This system can efficiently charge the traction battery with the low power generated by the solar panel. The power generated can charge the traction battery while the vehicle is parked.
SUBARU has developed EyeSight, which has Autonomous Emergency Braking (AEB), “Pre-Collision Braking System”. The concept is to minimize collision damage or if conditions allow, prevent the collision. Through a trial-and-error process, SUBARU has, and continues to enhance the performance of Pre-Collision Braking System. The latest Pre-Collision Braking System was refined to two points. The first is to hasten the reaction to crossing pedestrians coming out from behind obstacles to heighten the speed reduction effect. The other point is to improve the reaction to night-time pedestrians. The effectiveness has been raised by suppressing the drop in the recognition performance caused by peripheral darkness or the color of pedestrians' clothes. These improvements will offer a high level of safety. This report also describes details of traffic accident data, and comparing results of “with EyeSight” and “without EyeSight”.
A car crash simulator is a test device that can accurately reproduce the acceleration generated in a vehicle cabin at the time of a car crash. They are used in the research and development of passive safety devices such as seats and seatbelts, air bags and headrests, doors, car interiors, etc.
This article describes the achievements made so far and future efforts for the car crash simulator that Mitsubishi Heavy Industries Machinery Systems, Ltd. manufactures and sells.
Externally coupled transcutaneous energy transmission systems (ECTETS) can supply energy to implantable ventricular assist devices wirelessly. However, the magnetic field strength induced by this system at a frequency of 2 to 4 MHz exceeds the acceptable limit guideline provided by the International Special Committee on Radio Interference (CISPR 11). To reduce the emitted magnetic field strength, the leakage inductance of the secondary coil is cancelled by a resonance capacitor, which is inserted between a secondary coil and a rectifier circuit. An equivalent circuit of ECTETS is used to determine the capacitive value. DC-DC energy transmission efficiency and the emitted magnetic field strength of the prototype ECTETS were measured without and with resonance capacitance. The results indicated that the transmission efficiency could be increased from 79.3% to 84.0% and the emitted magnetic field strength could be reduced from 16 dBµA/m to 5.6 dBµA/m at 2.74 MHz by introducing a resonance capacitor.
Wireless power transfer that supply electric energy without wires is attracting the attention now. Many of the technologies use magnetic or electric field, but it have common problems that transmission efficiency depend on transmission distance. Therefore, we propose “sandwiched structure antenna” which having two pair of transmission antennas and reception antennas. Using the new structure, transmission efficiency can be made substantially constant inside a confined space.