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Hub AI
Ladder AI simulator
(@Ladder_simulator)
Hub AI
Ladder AI simulator
(@Ladder_simulator)
Ladder
A ladder is a vertical or inclined set of rungs or steps commonly used for climbing or descending. There are two types: rigid ladders that are self-supporting or that may be leaned against a vertical surface such as a wall, and flexible ladders, such as those made of rope or wire rope, that may be hung from the top.
The vertical members of a rigid ladder are called "stringers" or "rails" (US) or "stiles" (UK). Rigid ladders are usually portable, but some types are permanently fixed to a structure, building, or equipment. They are commonly made of metal, wood, or fiberglass, but they have been known to be made of tough plastic.
Ladders are ancient tools and technology. A ladder is featured in a Mesolithic rock painting that is at least 10,000 years old, depicted in the Spider Caves in Valencia, Spain. The painting depicts two humans using a ladder to reach a wild honeybee nest to harvest honey. The ladder is depicted as long and flexible, possibly made out of some sort of grass.
Rigid ladders are available in many forms, such as:
Rigid ladders were originally made of wood, but in the 20th century aluminum became more common because of its lighter weight. Ladders with fiberglass stiles are used for working on or near overhead electrical wires, because fiberglass is an electrical insulator. Henry Quackenbush patented the extension ladder in 1867.
The most common injury made by ladder climbers is bruising from falling off a ladder,[citation needed] but bone fractures are common and head injuries are also likely, depending on the nature of the accident. In addition to simple falls, the ladders themselves can also cause injury if they slip or slide on their support surface.
To avoid this, many ladders have flexible plastic or rubber feet or base pads which increase friction with the ground. However, if the friction foot is badly worn, smooth metal may contact a hard surface, increasing the chance of an accident. Ladder stabilizers are also available to increase the ladder's grip on the ground. One of the first ladder stabilizers or ladder feet was offered in 1936, and today they are standard equipment on most large ladders.
A common design for a ladder foot allows a pivoting flat friction foot to be used on relatively firm, level surfaces. For softer ground, the ladder foot can be pivoted so that a sharp toothed metal plate can be dug into the surface for better anchoring. For use on non-level ground, special ladder leveler extension legs can be extended or attached to compensate for the uneven terrain.
Ladder
A ladder is a vertical or inclined set of rungs or steps commonly used for climbing or descending. There are two types: rigid ladders that are self-supporting or that may be leaned against a vertical surface such as a wall, and flexible ladders, such as those made of rope or wire rope, that may be hung from the top.
The vertical members of a rigid ladder are called "stringers" or "rails" (US) or "stiles" (UK). Rigid ladders are usually portable, but some types are permanently fixed to a structure, building, or equipment. They are commonly made of metal, wood, or fiberglass, but they have been known to be made of tough plastic.
Ladders are ancient tools and technology. A ladder is featured in a Mesolithic rock painting that is at least 10,000 years old, depicted in the Spider Caves in Valencia, Spain. The painting depicts two humans using a ladder to reach a wild honeybee nest to harvest honey. The ladder is depicted as long and flexible, possibly made out of some sort of grass.
Rigid ladders are available in many forms, such as:
Rigid ladders were originally made of wood, but in the 20th century aluminum became more common because of its lighter weight. Ladders with fiberglass stiles are used for working on or near overhead electrical wires, because fiberglass is an electrical insulator. Henry Quackenbush patented the extension ladder in 1867.
The most common injury made by ladder climbers is bruising from falling off a ladder,[citation needed] but bone fractures are common and head injuries are also likely, depending on the nature of the accident. In addition to simple falls, the ladders themselves can also cause injury if they slip or slide on their support surface.
To avoid this, many ladders have flexible plastic or rubber feet or base pads which increase friction with the ground. However, if the friction foot is badly worn, smooth metal may contact a hard surface, increasing the chance of an accident. Ladder stabilizers are also available to increase the ladder's grip on the ground. One of the first ladder stabilizers or ladder feet was offered in 1936, and today they are standard equipment on most large ladders.
A common design for a ladder foot allows a pivoting flat friction foot to be used on relatively firm, level surfaces. For softer ground, the ladder foot can be pivoted so that a sharp toothed metal plate can be dug into the surface for better anchoring. For use on non-level ground, special ladder leveler extension legs can be extended or attached to compensate for the uneven terrain.
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