Simultaneous mass and time-varying grade estimation for heavy-duty vehicles

In this paper, two different approaches are proposed for simultaneous mass and grade estimation for heavy-duty vehicles. In the first method, an observer is used which can estimate mass and time-varying grade given their feasible range. The second approach is a recursive time-varying least square method with forgetting. Inclusion of multiple forgetting factors makes the algorithm suitable for simultaneous estimation of a constant and a fast time-varying parameter. Accurate mass estimation and good tracking of time-varying grade is demonstrated in simulations.