Planning multiple levels constant stress accelerated life tests

The authors propose a method for planning constant stress accelerated life tests (CSALT) in which the departure from the usual optimality criterion can be quantified. The scheme is illustrated using three stress levels CSALT. In particular, a contour plot is developed to provide the solution space for sample allocation at high stress and the two lower stress levels. Based on the output from the contour plot, three related approaches for planning CSALT are then presented. Finally, a numerical example is used to illustrate the procedures.