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Learning methods to adapt the planned path to individual drivers have been proposed to improve the comfort and trust provided by automated driving systems (ADSs). However, existing methods apply offline learning, even if they can accept the request to learn while driving (on-demand learning). Although several online learning methods are available, their learning results have not been applied in real-time for vehicle maneuvering. Focusing on obstacle avoidance, we propose on-demand online learning of preferred paths for individual drivers and investigate whether the proposed method improves the comfort and trust after learning. Unlike the existing methods, the proposed ADS can smoothly and arbitrarily transition between automated and manual driving, thereby learning preferred maneuvers whose results can be applied in real-time to obstacle avoidance. Accordingly, the proposed ADS includes mutual transfer of steering authority between the ADS and driver and curve modification according to the error between the planned path and actual vehicle trajectory. Experimental results show that the proposed ADS method improves the comfort and trust of drivers. In addition, the proposed ADS method learns the paths preferred by individual drivers during avoidance maneuvers to some extent and gradually adjusts the path according to the drivers preference through repeated learning.

While automated driving systems (ADSs), which correspond to level-two automated driving of Society of Automotive Engineers (SAE), are being developed actively, the ADS that learns the preference of drivers at an opportune time is required. In addition, there is a lack of assessments on ADS comfort. In this study, we focused on collision avoidance and developed an ADS that learns driver preference by driver intervention. By applying the gain-tuning and learning methods for gradual learning, the ADS can stably modify its behavior at an opportune time. The results of a driving simulator experiment indicated that driver comfort improved by using the proposed ADS. In addition, we confirmed that the ADS can guarantee usability during authority transfer in the learning process.

This paper describes the equivalence between Nyquist and Routh-Hurwitz stability criteria for analysis and design of the operational amplifier stability under some conditions. In the theoretical part, respective mathematical foundations of Nyquist and Routh-Hurwitz stability criteria have been deduced, and the equivalency of their mathematical foundations is shown. In the verification part, our statement is confirmed with LTspice simulations at transistor level circuits.

This paper proposes to use Routh-Hurwitz stability criterion for analysis and design of the opamp stability, when its small equivalent circuit is derived; this can lead to explicit stability condition derivation for opamp circuit parameters, and this is very effective especially for multi-stage opamps. The proposed method has been verified by two two-pole amplifiers with theoretical analysis and SPICE simulations, as examples.

The objective of the present study is to develop a microwave power transmitting system for a Mars observation airplane. A wide-ranging continual Mars observation is becoming important for understanding physical properties of Mars. We suggested a transmitting system with a magnetron-based phased array. In this paper, we conducted auto tracking experiments and confirmed position detection error of the auto tracking system caused declines of received power. We also demonstrated transmitting power control and confirmed that the power control provided approximately uniform DC voltage for a ground experiment airplane.

The objective of the present study is to develop a microwave power transmitting system for a Mars observation airplane. We suggest a phased array antenna composed of "power-variable phase-controlled magnetrons (PVPCM)" for the transmitting system. We confirmed the PVPCM had proper response speed to chase the airplane. We constructed PVPCMs for a phased array antenna through designing an integrator for a phase locked loop in the PVPCM, and we realized a stable power variation of the PVPCM. We confirmed realization of a phased array antenna with PVPCMs and transmitting power control.