def gen_ss(seed, goal, buff=[ss_start]*4):
    """
    Returns a sample space given a seed state, goal state, and buffer.

    """
    return [(min([seed[0], goal[0]]) - buff[0], max([seed[0], goal[0]]) + buff[1]),
            (min([seed[1], goal[1]]) - buff[2], max([seed[1], goal[1]]) + buff[3]),
            (-np.pi, np.pi),
            (0.9*velmax_pos[0], velmax_pos[0]),
            (-abs(velmax_neg[1]), velmax_pos[1]),
            (-abs(velmax_neg[2]), velmax_pos[2])]