Submitted by
ShashikantChoudhari

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Introduction:-
Currently, 50 percent of all robots in use today are used in automobile manufacture. As manufacturing becomes more automated, there will be less need for human workers in the auto industry. As robotics technology improves, it is conceivable that the auto industry will become fully automated. Almost all manufacturing robots are single arms with computer controls, and do not look like a typical science-fiction "robot." Robots in the automotive industry are largely used as assembly line workers. With precision programming and steel-renforced strength, robot arms could piece together major auto body parts in seconds.
Robots were initially retained to perform precise welding chores and other repetitive tasks that humans had long found boring, monotonous and injurious. By using robots to weld, handle dangerous objects and place items, auto manufacturers were able to ensure a consistent product with a minimum of worker injury.
WHAT IS ROBOT-
The term robot comes from the Czech word robota, generally translated as "forced labor." This describes the majority of robots fairly well. Most robots in the world are designed for heavy, repetitive manufacturing work. They handle tasks that are difficult, dangerous or boring to human beings.
Industry robots make cars and other consumer and business products. A Cartesian robot has parts oriented left and right, forward and backward, and up and down.
A cylindrical robot is a robot whose movement traces a cylinder outline. A polar robot's movement traces a sphere in the air. One type of robot operates remotely but is controlled from another location. The Mars rovers, armed drones and underwater explorer vehicles are examples.
Another type of robot goes into danger zones, such as a crater of an active volcano, or a cave used by hostile forces.
Laws of Robotics
1. A robot may not injure a human being, or, through inaction, allow a human being to come to harm
2. A robot must obey orders given it by human beings, except where such orders would conflict with the First Law.
3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law
WHAT IS ROBOTIC ARM:-
The most common manufacturing robot is the robotic arm. A typical robotic arm is made up of seven metal segments, joined by six joints. The computer controls the robot by rotating individual step motors connected to each joint (some larger arms use hydraulics or pneumatics). Unlike ordinary motors, step motors move in exact increments. This allows the computer to move the arm very precisely, repeating exactly the same movement over and over again. The robot uses motion sensors to make sure it moves just the right amount.
FEATURES OF ROBOTIC ARM:-
An industrial robot with six joints closely resembles a human arm - it has the equivalent of a shoulder, an elbow and a wrist. Typically, the shoulder is mounted to a stationary base structure rather than to a movable body. This type of robot has six degrees of freedom, meaning it can pivot in six different ways. A human arm, by comparison , has seven degrees of freedom.
Your arm's job is to move your hand from place to place. Similarly, the robotic arm's job is to move an end effector from place to place. You can outfit robotic arms with all sorts of end effectors, which are suited to a particular application. One common end effector is a simplified version of the hand, which can grasp and carry different objects . Robotic hands often have built-in pressure sensors that tell the computer how hard the robot is gripping a particular object. This keeps the robot from dropping or breaking whatever it's carrying . Other end effectors include blowtorches, drills and spray painters.
Industrial robots are designed to do exactly the same thing, in a controlled environment, over and over again. For example, a robot might twist the caps onto peanut butter jars coming down an assembly line. To teach a robot how to do its job, the programmer guides the arm through the motions using a handheld controller. The robot stores the exact sequence of movements in its memory, and does it again and again every time a new unit comes down the assembly line.
CONTROLLING
The most common manufacturing robot is the robotic arm. A typical robotic arm is made up of seven metal segments, joined by six joints. The computer controls the robot by rotating individual step motors connected to each joint (some larger arms use hydraulics or pneumatics). Unlike ordinary motors, step motors move in exact increments . This allows the computer to move the arm very precisely, repeating exactly the same movement over and over again. The robot uses motion sensors to make sure it moves just the right amount.
The robotic arm's job is to move an end effector from place to place. You can outfit robotic arms with all sorts of end effectors, which are suited to a particular application. One common end effector is a simplified version of the hand, which can grasp and carry different objects. Robotic hands often have built-in pressure sensors that tell the computer how hard the robot is gripping a particular object. This keeps the robot from dropping or breaking whatever it's carrying. Other end effectors include blowtorches, drills and spray painters.
Parameters
Arms are typically defined by fourteen different parameters.
Number of Axes – Two axes are needed to reach any point in a plane. Three are required to reach a point in space. Roll, pitch, and yaw control are required for full control of the end manipulator.
Degrees of Freedom– Number of points a robot can be directionally controlled around. A human arm has seven degrees; articulated arms typically have up to 6.
Working Envelope – Region of space a robot can encompass.
Working Space – The region in space a robot can fully interact with.
Kinematics – Arrangement and types of joints (Cartesian, Cylindrical, Spherical, SCARA, Articulated, Parallel)
Payload – Amount that can be lifted and carried
Speed – May be defined by individual or total angular or linear movement speed
Acceleration – Limits maximum speed over short distances. Acceleration is given in terms of each degree of freedom or by axis.
Accuracy – Given as a best case with modifiers based upon movement speed and position from optimal within the envelope.
Repeatability – More closely related to precision than accuracy. Robots with a low repeatability factor and high accuracy often need only to be recalibrated.
Motion Control – For certain applications, arms may only need to move to certain points in the working space.
Power Source – Electric motors or hydraulics are typically used, though new methods are emerging and being tested.
Drive – Motors may be hooked directly to segments for direct drive.
Compliance – Measure of the distance or angle a robot joint will move under a force.
TYPES:
Cartesian Coordinate Robot Arm:
Axes in the robot arm are perpendicular. One axe is part of a pole, while the other axe is a telescoping arm. One of the two parts of the arm is attached to a base, which the robot arm can rotate on. This part of the arm is long and thin. The other robot arm wraps around the long and thin robot arm and can rotate around it. The robot arm has the ability to telescope, allowing it to reach out and interact with other objects.
Cylindrical Coordinate Robot Arm:
This arm has a cylinder that is attached to a base. This cylinder revolves on the base, allowing the robot arm to interact with objects in all directions.. For the other long metal shaft, one end is attached to the previous metal shaft, while the other end is attached to a wrist that is capable of rotating. The rotating functions are controlled with a rack and pinion system. The rack and pinion is operated by a long, grooved strip and a grooved gear.
Spherical Robot Arm:
This robot arm has two pivotal joints, consisting of rings turning on pivots. There is one prismatic joint which consists of one rectangular object sliding within a larger rectangular object. All of this is encased in a sphere which the robot arm is attached to. The two rotary joints are perpendicular, allowing the robot arm to rotate to the left and right and also rotate up and down..
SCARA Robot Arm:
The joints on this arm have a Z-shape with axes on both ends. There is a pivotal joint on both ends of this Z-shaped arm and one pivotal joint in the middle. The bottom part of the SCARA arm is attached to a pedestal, which attaches to the rest of the robot.