double vOptimal = 0;// optimal velocity
final double s0 = getMinimumGap();
OptimalVelocityFunctionEnum variant = param.getOptimalSpeedFunction();
if (variant == OptimalVelocityFunctionEnum.BANDO) {
// standard OVM function (Bando model)
// scale OVM/VDIFF so that v0 represents actual desired speed
final double v0Prev = v0Local / (1.0 + Math.tanh(betaLoc));