During the early days of the steam engine and combine harvester, sophisticated mechanical mechanisms were invented out of necessity. Largely a lost art, advanced mechanisms of this sort are still being developed in a few fields, such as advanced windshield-wiper designs that cover a high percentage of large windshields, and automatic and continuously-variable transmissions in automobiles.
With the development of sophisticated robotic vehicles like iHop, we are witnessing a resurgence in the creative design of multifunctional mechanisms built to fit a variety of complex needs. Note in particular the dual four-bar mechanism used to coordinate the leg motion of iHop v.2, and the interconnected six-bar mecahnisms used to coordinate the leg motion of iHop v.3, as indicated above. Both of these designs are capable of locking the leg during upright roving, and easily releasing this lock to initiate hopping. In addition, both designs provide a continuously-variable transmission of torque during the hopping motion of the vehicle, supplying high torque when it is needed (at low speeds), and high speed when it is needed (at low torques). These features are essential to the proper functioning of the iHop design.
Copyleft 2011 by Thomas Bewley. Some rights reserved.