Research On The Trajectory Controlling Method For The Variable Structure Motorcycle Helmet

This paper designs a new type of variable structure motorcycle helmet, whose chin-guard can be transformed between the full-helmet status and the half-helmet status as needed. The helmet creatively adopts the constraint mechanism of double movement nails combined double track grooves and can successfully guide the chin-guard movement and setting according to the predetermined trajectory, and thus smoothly accomplishing the chin-guard's lifting, climbing, passing zenith, falling and closing in the helmet shell. The paper discusses the chin-guard's trajectory planning principles and realizing methods, and then gives a design case for the constraint slot tracks in detail. The experiment shows that the new type helmet can reliably realize helmet structure conversion between full-helmet and half-helmet and fully meet the design requirements.