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Does anyone know why product picking carts like this, commonly found in warehouses and supermarkets, are mostly just 3 or 4 shelves high?
Is it because of ergonomic issues or mechanical ones? Couldn't these carts be twice as tall and have their capacity doubled?
One of the key factors would be the height of the blue baskets and the maximum weight such baskets can hold. If the baskets were shorter in height, more shelves could be accommodated by the carts.
The maximum weight that can be carried by the baskets, or trays, depending on what is being carried, is an important health and safety matter. It is bad design and poor practice to have equipment that can injure people. Injured people may require time off work, with its associated economic issues for the employer and employee and there are added costs to employers with higher costs for workers compensation schemes and potential law suits.
Bread carts have many more shelves because the loaves of bread are short in height and have relatively low weight.
If the cart was twice the height, apart from the doorway, the operator would needs steps or a ladder to get the top ones - safety considerations come to mind as well as time... would it be quicker with lower carts and no ladder.
It's a combination of structural and ergonomical.
Additionally, there is another one, which is present in the photo. Look at the door just behind the cart. If the cart was twice this height, it would not fit into the door.
It it were twice as wide, then it would be difficult to maneuver in tight spaces.
If you look at it, it takes about the same volume in space as an large adult person. The reasoning behind it, is that you want it fit more or less where the person fits. Additionally, if you make it too large, then you probably need to start thinking about motors to move it and steer it.
