In this paper, a new class of polynomial functions equipped with a parameter is used, which is applied to approximate the gBBMB. In this method, the first, time discretization of the gBBMB equations is made by using finite difference approaches. Then, at any spatial point, a nonlinear equations system is generated. Using the collocation points and solving a nonlinear system in the least squares method, the coefficients of functions are obtained. In some examples, a linearization is performed first, and then the collocation method is applied. (C) 2019 Elsevier Inc. All rights reserved.