Advance Modeling of a Skid-Steering Mobile Robot for Remote ...

Introduction 5interaction at the kinematic level. A wheel/ground friction model, based on the wheel longitudinalslip, is incorporated into the robot dynamic model for both the longitudinal andlateral friction forces [10], [4], [5], [11], [12]. After presenting the kinematic and dynamicmodel proposed in literature until nowadays, a novel three-dimensional generalized dynamicmodel for SSMRs is provided by including a three-dimensional non-holonomic constraintand by considering the tire reaction forces as unknown functions.In Chapter 3, some experimental data acquired from three 1-axis accelerometers and a forcesensor are presented and analyzed to characterize the nature of the robot vibrations and thetire reaction forces. Consequently, a spring-mass-damper model separately for tire lateral,longitudinal and vertical reaction force is further discussed in Chapter 4. A dynamic frictionmodel, based on the work proposed in [4], [5], is also provided in this chapter to include thecontribution of the wheel longitudinal slip into the reaction force model.A complete identification of the robot geometric and dynamic parameters is provided in providedin Chapter 5, including the identification of the Roll, Pitch and Yaw dynamics. Finally,the Simulink model of the three-dimensional skid-steering motion reproducing the real systembehavior is presented in Chapter 6. In this chapter, also the results of the simulation arepresented and compared to the data acquired from the accelerometers and the force sensor,in order to validate the proposed model.