Plotter
Plotter
A plotter is used for vector graphics output to draw graphs, maps, blueprints of ships, buildings, etc. Plotters use pens of different colors (cyan, magenta, yellow and black) for drawing. Plotters draw continuous and accurate lines, in contrast to printers where a line is drawn as closely spaced dots. Plotter is a slow output device and is expensive. Plotters are of two kinds—drum plotter and flatbed plotter. In a drum plotter, pens mounted on the carriage are stationary and move only horizontally; for vertical movement, the drum on which the paper is fixed moves clockwise and anti-clockwise. In a flatbed plotter, the paper is fixed on a flat bed. The paper is stationary and the pens mounted on the carriage move horizontally and vertically to draw lines. Plotters are mainly used for drawings in AUTOCAD (computer assisted drafting), Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) applications.
There are Two commonly types of plotters:
1. Drum plotter
2. Flatbed plotter
Drum Plotter
In a drum plotter, the paper on which the design is to be made is placed over a drum that can rotate in both clockwise and anti-clockwise directions to produce vertical motion. The mechanism also consists of one or more penholder mounted perpendicular to the drum‘s surface. The pen(s) clamped in the holder(s) can move left to or right to left to produce horizontal motion. A graph-plotting program controls the movements of the drum and pen (s) that is, under computer control, the drum and pen(s) move simultaneously to draw designs and graphs; sheet placed on the drum. The plotter can also annotate the designs and graphs so drawn by using the pen to draw characters of various sizes. Since each pen is program selectable, pens having ink of different colors can be mounted in different holders to produce multi-colored designs.
Drum Plotter
Flatbed Plotter
A flatbed plotter plots a design or graph on a sheet of paper spread and fixed over a rectangular flatbed table. In this type of plotter, normally the paper does not move and the pen holding mechanism provides all types of motions necessary to draw complex designs and graphs. That is under computer control, the pen(s) in the required manner to draw design and graphs on the sheet placed on the flatbed table. The plotter can also annotate the designs and graphs so drawn by using the pen to draw characters of various sizes. Provision is also there to mount more than one pen in the pen(s) holding mechanism.
Flatbed Plotter