ABSTRACT This paper describes a driving control algorithm based on a skid steering for a Robotic Vehicle with Articulated Suspension (RVAS). The RVAS is a kind of unmanned ground vehicle based on a skid steering using independent in- wheel drive at each wheel. The driving control algorithm consists of four parts: a speed controller for following a desired speed, a lateral motion controller that computes a yaw moment input to track a desired yaw rate or a desired trajectory according to the control mode, a longitudinal tire force distribution algorithm that determines an optimal desired longitudinal tire force and a wheel torque controller that determines a wheel torque command at each wheel in order to keep the slip ratio at each wheel below a limit value as well as to track the desired tire force. The longitudinal and vertical tire force estimators are required for the optimal tire force distribution and wheel slip control. A dynamic model of the RVAS is developed for simulation study and validated using the vehicle test data. Simulation and vehicle tests are conducted in order to evaluate the proposed driving controller. It is found from simulation and vehicle test results that the proposed driving controller provides satisfactory motion control performance according to the control mode. INTRODUCTION Recently, diverse unmanned ground vehicles are developed in order to conduct multi-tasks such as logistics supports, surveillance and light combat operation. In this paper, as a part of autonomous vehicle control for military or roboticvehicle, skid steering based autonomous driving control algorithm is investigated. Robotic Vehicle with Articulated Suspension (RVAS), as shown in Figure.1, is a kind of unmanned ground vehicle based on a skid steering using independent in-wheel drive at each wheel. The RVAS, unlike the conventional wheeled vehicles, is not equipped with steering linkages. Instead, it is steered through differential traction force which is occurred from in-wheel motor at each wheel. Steering in this fashion requires much more power consumption than in kinematic steering using Ackerman's linkages [ 1, 2]. However, this offers simple structure and more room in the vehicle for mission equipment installment. In the aspect of mobility, the RVAS benefits from its in- wheel drives and articulated suspensions, which provide an independent wheel traction control capability and a great improvement of obstacle negotiation ability, respectively. This paper focuses on the control strategy based on skid steering of the RVAS in order to track a desired yaw rate or a desired trajectory according to the control mode. A dynamic model for the RVAS is developed and validated using test data. Simulation studies and vehicle tests are conducted in order to evaluate the proposed driving controller. It is found from the simulation and test results that the proposed driving controller based on a skid steering provides good maneuverability. Skid Steering based Driving Control of a Robotic Vehicle with Six In-Wheel Drives2010-01-0087 Published 04/12/2010 Juyong Kang and Wongun Kim Seoul National Univ. Kyongsu Yi Seoul National Univ Soungyong Jung and Jongseok Lee Samsung Techwin Copyright © 2010 SAE International SAE Int. J. Passeng. Cars - Mech. Syst. | Volume 3 | Issue 1 131Downloaded from SAE International by American Univ of Beirut, Monday, July 30, 2018Figure.1. Robotic Vehicle with Articulated Suspension (RVAS) 2. DYNAMIC MODEL OF A VEHICLE WITH INDEPENDENT IN-WHEEL DRIVE 2.1. DEVELOPMENT OF VEHICLE DYNAMIC MODEL A full dynamic model of the RVAS is developed to conduct numerical simulation studies. The full dynamic model of the RVAS is designed as three parts; driving system, arm dynamic model and vehicle body dynamic model as shown in Figure.2. The driving system contains an in-wheel motor model, a wheel dynamic model and a tire model. The arm dynamic model determines the dynamic behaviors of i-th arm rod. The vehicl