The great Russian mathematician, founder of the St. Petersburg mathematical school, academician of the St. Petersburg Academy of Sciences and 24 academies of the world, Pafnuty Chebyshev (1821-1894) approached the problem of converting rotational motion along a circle (for example, from a steam engine) into translational motion of a machine in an original way.
Chebyshev, being a professor at St. Petersburg University, spent most of his salary on the invention and manufacture of his mechanisms. In his scientific activity, he combined theory and practice, developed the theory of uniform approximations and was the founder of the mathematical theory of mechanism synthesis.
Chebyshev owns a lot of original ideas in the field of building mechanisms, which can be viewed on the website tcheb.ru in the form of animated 3D models. The upper point of the conditional “connecting rod”, if we give an analogy with a crank mechanism, describes a trajectory resembling a mushroom cap. In this case, the lower part of the trajectory is a straight line. By attaching a vertically standing “leg” with a foot to the upper end of this beam, we will get the basis for a walker.
In the mechanism assembled from lego, the vertical position of the legs is provided by a parallelogram – a second beam is needed, which will be parallel to the long side of the “lambda mechanism”.