Abstract

23:T500,Abstract

The bumpy-ridge structure applied in the field of heavy equipment is analysed based on fracture mechanics and contact theory. At the same time, the elastic—plastic contact of the ridges is simulated using the finite element method. Having been researched, the separated bumpy-ridge structure can be seen as a special integral structure that has a through crack. It was also found that, as long as there are adequate normal forces and treated contact surfaces, this kind of separated structure has the ability to resist detachment and parallel slide. The height of the notch and radius of the contact zone are the foremost indexes affecting the application of the bumpy-ridge technique, and these parameters are influenced by several factors, such as the shape of the ridges, the curvature of the contact point, the distance between neighbouring ridges, etc. The elastic contact of the ridge can be solved completely by the use of theoretical calculation and graphical method. Through comparison with the elastic contact, some principles of the elastic—plastic contact can be obtained with a finite element analysis method. A bumpy-ridge structure has been successfully applied to a 350 MN die forging press and a 360 MN extrusion press in China.

24:T41d,

In nature, sensory and physical characteristics of the environment tend to match; for example, a surface that looks bumpy is bumpy. In human-built environments, they often don’t. Here, we report observations from people exploring if mismatch between visual and physical characteristics affected their perceived walking experience. Participants walked across four flat floors, each comprising of a visual illusion: two patterns perceived as alternating 3D “furrows and ridges,” the Primrose Field illusion, and a variant of the Cafe Wall illusion as a control pattern without perceived 3D effects. Participants found all patterns intriguing to look at; some describing them as “playful” or “gentle.” More than half found some of the patterns uncomfortable to walk on, aversive, affecting walking stability, and occasionally even evoking fear of falling. These experiences raise crucial research questions for the vision sciences into the impact of architectural design on well-being and walkability.

Search results

Analysis and simulation on the bumpy-ridge structure of heavy equipment

Walking on Visual Illusions