2021 年 57 巻 6 号 p. 293-303
On-/off-drive-type tracked vehicles are machines used for agricultural and snow vehicles. The kinematics model of this vehicle is a nonlinear system (called a driftless system), for that reason which general linear control theory cannot be used. One method to solve this problem is to use conversion to a time-state control form, which considers one of the state variables as a time axis. This conversion allows us to make the model a linear system. In addition, a converting input law in which the continuous-valued inputs obtained by state feedback are converted into discrete-valued inputs, is used for discrete-valued input systems control. However, when the above-mentioned conversion input law is applied to a system with a time-state control form, the theoretical conditions cannot be satisfied and errors may occur. This problem not only leads to theoretical discrepancies but also causes large response degradation due to excessive storage of errors in a servo system that includes an integrator. Therefore, in this study, we propose a method to reduce the theoretical discrepancies and prevent response degradation by adjusting the input time for on-/off-drive-type tracked vehicle control, using a time-state control form. We applied the proposed method to a linear tracking control using a servo system and confirmed its effectiveness through numerical simulations and experiments.