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Recently, customers' demands for future mobility have increased, such as movement in narrow spaces, increased driving freedom, and ease of parking. The key technology to meet these demands is the four-wheel independent steering system. In this study, we introduce the concept design process for a four-corner steering module and how to prove the design. In addition, we introduce a control method for basic driving modes, such as short U-turn, diagonal driving, crab driving, and zero radius turning. Finally, we propose a special driving mode using the instantaneous rotation center of the 4WS system.

This paper describes a failsafe system of automated driving vehicles. The failsafe system consists of the following two parts: sliding mode observer-based environment sensor, chassis sensor fault detection, and emergency deceleration control. Two sliding mode observers are designed to reconstruct the fault of acceleration and environment sensor(Lidar) in a longitudinal direction. In the environment sensor's fault detection part, the longitudinal vehicle model receives clearance and relative velocity values. Therefore, failure diagnosis is possible regardless of environmental sensors, such as radar, lidar, and camera. This paper's sensor data is the failure of Delphi's Electronically Scanning Radar (ESR) and Ibeo's LUX Lidar installed in an autonomous vehicle. The emergency deceleration control algorithm employs the sliding mode control with adaptive convergence time. In the event of a failure, it is significant to control the vehicle within a short period safely.

This paper presents a 3D dynamic simulation model of a wheel loader. The objective of development of the wheel loader dynamic simulation model is to investigate power flow under both working and driving conditions. The wheel loader dynamic simulation model consists of 3 parts: Vehicle mechanical powertrain module, Hydraulic modules for working and steering, and Vehicle dynamic module. Vehicle powertrain module consists of engine, torque converter and transmission. Hydraulic modules consist of pump, valve, cylinder and attachments. In this paper, hydraulic powertrain is managed only for steering system because this paper has been focused on dynamic analysis of mechanical powertrain and vehicle. Front and rear bodies are connected by pin in the center of steering system. Action/reaction forces and moments applied to the pin are calculated by solving front/rear dynamic simultaneous equations.