This paper proposes a method for a snake robot to fit ordered points and thus generate body shape. A non-smooth backbone curve consisting of straight line segments is constructed by sequentially connecting the ordered points, and then the bending and twist angles at the singularities are obtained iteratively to obtain the joint angles of the snake robot. Fitting the shape of a snake robot using this method does not depend on obtaining a backbone curve with known curvature and torsion, greatly expanding the applicability of the fitting method. In this paper, the validity of the fitting method is verified by simulation, which generates a shape that resembled a biological snake coiled on the ground.

This paper presents a gait design method for a snake robots fit non-smooth backbone curves. Introducing bending angles at the points where the directions of tangent vectors of the backbone curve changes discontinuously breaks the restriction that the left and right limits of tangent vectors at each point on the backbone curve fitting the target shape of the snake robot must be the same, which makes the design of the target trunk curve simpler and more convenient. The method was utilized to design gaits for spanning motions between parallel and intersecting bars. The gaits in both scenarios are demonstrated in simulation to validate the effectiveness of the fitting method and the gaits.