HomeE-mailрусская версия

February 24, 2003
Why two 8-kilo suitcases are easier to carry than one 10-kilo suitcase?

It is much easier to carry two 8-kilo suitcases then one 10-kilo suitcase.
Is it an obvious paradox? No, it is not, because when two hands are loaded, the muscles experience a uniform load. If the load is concentrated on one side of the body, the load on the muscles is much greater. Part of the muscles holds the load, and the rest of them must ensure equilibrium while walking.

Image: Mary Soroka
In general, it would be better to carry a heavy load in a kind of a post-bag hanging on a shoulder, or in a backpack. A backpack is an excellent and ergonomic alternative for a shoulder bag, which only provides load on one shoulder. Whereas a backpack distributes load symmetrically between both shoulders and, in addition, partially distributes pressure over the back.
However, a backpack is not ideal either. A heavy backpack weights down shoulders, changes the normal center of gravity of a body, spoils posture and makes one stoop.
The inventor Shimanov found a simple way out. He additionally divided a backpack into two parts (patent application 9127671, Russia). One part is fixed on the back as an ordinary backpack, while the other one is fixed on the breast. The load is distributed so that it allows an upright posture to be preserved.
Trully, full-breasted women will hardly like this invention.  


The source of information: “Technics for young people”. 

The second TRIZ formula / Seminar of TRIZ practitioners (TRIZ Colloquium #2) / Seminar of TRIZ practitioners (TRIZ Colloquium #1) / Evolution of Soil Cultivation Methods / Nari, nari, genari... / TRIZ in a Bi-system with Lean Sigma / Using “Value-Engineering Analysis + TRIZ” method for improoving the stripping grain-harvesting machine / Disaster in the Gulf of Mexico (Continuation) / Disaster in the Gulf of Mexico / TRIZ in the World of Science Where Does It Fit? / Аlgorithm of work on production inventive projects / History of Gallic Reaper / Emotional Toyota / Stretch jogging shoes / Transfer to the microlevel as one of the main display evolution trends  / Transformation of structurally similar elements of technical system / “Bronze Horseman” / TRIZ-Principles for Art-Composition / Man and Technical System (part II) / Motor boat-fisher
Evolution / Ideas / Old and new tales / Solved problems / Tools and methods
Algorithm of problem solving / Altshuller's principles / Contradiction / Evolution tree / Ideal final result / Physical effects / Resources / ...
Automobile / Display / Medicine / Pleasant trifles / Safety / Special property materials / Usability / ...
TRIZ survey seminar / Forecasting as a business management method / Patent circumventing technology

Copyright © 2002-2024 «Generator»
Authors: Nikolay Shpakovsky, Elena Novitskaya