Design of sliding mode observer for the estimation of train car positions and in-train forces

For the control design of freight trains, estimation in-train forces is crucial to avoid safety issues caused by possible failure car couplers under excessive stress. However, and relative positions adjacent train cars are not directly measurable. To address this issue, paper designs estimators using only locomotive-based measurements. Using multi-point model, a cascade structure robust sliding mode differentiators developed. It provides finite-time forces. Simulation results illustrate feasibility proposed approach.