Humanoid Robot

humanoid robot is a robot with its overall appearance based on that of the human body, allowing interaction with made-for-human tools or environments. In general humanoid robots have a torso with a head, two arms and two legs, although some forms of humanoid robots may model only part of the body, for example, from the waist up. Some humanoid robots may also have a 'face', with 'eyes' and 'mouth'. Androids are humanoid robots built to aesthetically resemble a human.
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A humanoid robot is an autonomous robot because it can adapt to changes in its environment or itself and continue to reach its goal. This is the main difference between humanoid and other kinds of robots. In this context, some of the capacities of a humanoid robot may include, among others:

• self maintenance (recharge itself)
• autonomous learning (learn or gain new capabilities without outside assistance, adjust strategies based on the surroundings and adapt to new situations)
• avoiding harmful situations to people, property, and itself
• safe interacting with human beings and the environment

Like other mechanical robots, humanoid refer to the following basic components too: Sensing, Actuating and Planning and Control. Since they try to simulate the human structure and behaviour and they are autonomous systems, most of the times humanoid robots are more complex than other kinds of robots.

This complexity affects all robotic scales (mechanical, spatial, time, power density, system and computational complexity), but it is more noticeable on power density and system complexity scales. In the first place, most current humanoids aren’t strong enough even to jump and this happens because the power/weight ratio is not as good as in the human body. The dynamically balancing Anybots Dexter can jump, but poorly so far. On the other hand, there are very good algorithms for the several areas of humanoid construction, but it's very difficult to merge all of them into one efficient system (the system complexity is very high). Nowadays, these are the main difficulties that humanoid robots development has to deal with.

Their creators' goal for the robot is that one day it will be able to both understand human intelligence, reason and act like humans. If humanoids are able to do so, they could eventually work alongside humans. Another important benefit of developing androids is to understand the human body's biological and mental processes, from the seemingly simple act of walking to the concepts of consciousness and spirituality. Right now they are used for welding. In the future they can greatly assist humans by welding and mining for coal.