Sunday, January 27, 2019

Introduction to robotics



What is a robot?

A robot is a machine which senses the environment and makes decisions according to the perceived data and takes an action based upon the perceived data.

The Essential elements of robotics: Sense, Think, Act.

Technically these essential elements are known as
  1. Perception
  2. Decision making
  3. Actuation
Lets briefly study about these topics



Perception : 

Robot perceives the world around them through the use of sensors. Robot sensors are analogous to our human senses like sight, hearing, and touch
There are many different kinds of sensors used in robotics, few are listed below
  • A robot eyes might be cameras, LiDAR or radar units or even ultrasound.
  • A microphone could be a robot's ears.
  • Senses of touch might be achieved through the use of temperature and pressure sensors.
  • Senses like taste and smell can be achieved using chemical analyzers.
Robots can also be equipped with sensors that have no human analogy like GPS( Global Positioning System), to specify exact location on the earth. A Barometer to detect altitude or even a magnetic field sensor to detect the heading direction (Basically a compass).


Decision making :

Based on data from various sensors and its own internal state, a robot needs to take decisions in order to accomplish any given task. These decisions can be as simple as yes or no question, like "Is the target object present on the table ?" or they can be externally complex like navigation an unknown environment. In practice, however, the decision making process robotics is complex and require answering many questions to find a path through a complex tree of possibilities.


A robot needs to use a motion blending algorithm to decide how to get from one place to another place and then use a control algorithm to stay on track

Actuation:

Actuation devices are the components of the robot that make it move
Best known actuators are electric motors, servos and stepper motors and also pneumatic or hydraulic cylinders. Today there are new alternatives, some which wouldn't be out of place in a good SF-movie. One of the new types of actuators are Shape Memory Alloys (SMA). These are metal alloys that shrink or enlarge depending on how warm they are. Another new technique is the use of air-muscles.
  1. Motors
  2. Shape Memory Alloys
  3. Air muscle
  4. Linear Electromagnetic
  5. Piezoelectric Actuators
  6. Pneumatics/Hydraulics
  7. Miniature internal combustion engines




Introduction to robotics

What is a robot? A robot is a machine which senses the environment and makes decisions according to the perceived data and takes an...