Robotics Co-ordinate System

Co-ordinate System

A coordinate system defines a plane or space by axes from a fixed point called the origin. Robot targets and positions are located by measurements along the axes of coordinate systems. A robot uses several coordinate systems, each suitable for specific types of jogging or programming.

The Robots are mostly divided into four major configurations based on their appearances, sizes, etc. such as:

·Cylindrical Configuration,

·Polar Configuration,

·Jointed Arm Configuration, and

·Cartesian Co-ordinate Configuration.

Cylindrical Configuration:

This kind of robots incorporates a slide in the horizontal position and a column in the vertical position. It also includes a robot arm at the end of the slide. Here, the slide is capable of moving in up & down motion with the help of the column. In addition, it can reach the work space in a rotary movement as like a cylinder.

Example: GMF Model M1A Robot.

Advantages:

·      Increased rigidity, and

·      Capacity of carrying high payloads. Disadvantages:

·      Floor space required is more, and

·      Less work volume.

Polar Configuration:

The polar configuration robots will possess an arm, which can move up and down. It comprises of a rotational base along with a pivot. It has one linear & two rotary joints that allows the robot to operate in a spherical work volume. It is also stated as Spherical Coordinate Robots.

Example: Unimate 2000 Series Robot.

Advantages:Long reach capability in the horizontal position.

Disadvantages:

·Vertical reach is low.

Jointed Arm Configuration:

The arm in these configuration robots looks almost like a human arm. It gets three rotary joints and three wrist axes, which form into six degrees of freedoms. As a result, it has the capability to be controlled at any adjustments in the work space. These types of robots are used for performing several operations like spray painting, spot welding, arc welding, and more.

Example: Cincinnati Milacron T3 776 Robot

Advantages:

·      Increased flexibility,

·      Huge work volume, and

·      Quick operation. Disadvantages:

·      Very expensive,

·      Difficult operating procedures, and

·      Plenty of components.

Cartesian Co-ordinate configuration:

These robots are also called as XYZ robots, because it is equipped with three rotary joints for assembling XYZ axes. The robots will process in a rectangular work space by means of this three joints movement. It is capable of carrying high payloads with the help of its rigid structure. It is mainly integrated in some functions like pick and place, material handling, loading and unloading, and so on. Additionally, this configuration adds a name of Gantry Robot.

Example: IBM 7565 Robot.

Advantages:

·        Highly accurate & speed,

·        Fewer cost,

·        Simple operating procedures, and

·        High payloads.

Disadvantages:

·      Less work envelope, and

·      Reduced flexibility.

Work Envelop

It is the shape created when a  manipulator reaches forward, backward, up and down.

These distances are determined by the length of a  robot's arm and the design of its axes. Each axis contributes its own range of motion.

A robot can only perform within the confines of this  work envelope. Still, many of the  robots are designed with considerable flexibility. Some have the ability to reach behind themselves. Gantry robots defy traditional constraints of work envelopes. They move along track systems to create large work spaces.

Technical Features of an Industrial Robot

The technical features of an industrial robot determine its efficiency and effectiveness at performing a given task. The following are some of the most important among these technical features.