Manual Assembly uses relatively simple tools and generally is economical for small lots.Because of the dexterity of the human hand and fingers and their capability for feedback through various senses, workers can manually assemble even complex parts without much difficulty.In spite of the use of sophisticated mechanism,robots and computer controls,the aligning and placing of a simple square peg into a square hole involving small clearances can be difficult in automated assembly--yet the human hand is capable of doing this simple operation with relative ease.
(Kalpakjian S.,Schimid S.R.,Manufacturing Engineering and Technology 5th edition,p. 1180)
Derivative System for CAPP Systems
It also called the variant system.These computer files contain a standart process plan for the part to be manufactured.A search for a standard process plan for rhe part to be manufactured.A research for a standard plan is made in the database by a code number for the part.The plan is retrieved,displayed for review and printed as a routing sheet.
The variant-process plan includes information such as the types of tools and machines to be used the squence of manufacturing operations to be performed,the speeds,the feeds and the time required for each sequence.Minor modification of an existing process plan also can be made.In the variant system,if the standard plan for a particular part is not be computer files,a plan that is close to it is retrieved.If a routing sheet does not exist,one is made for new part and stored in computer memory.
(Kalpakjian S.,Schmid S.R.,Manufacturing Engineering and Technology 5th edition,p. 1205)
Numerically Controlled Robot
The numerically controlled robot is programmed and operated much like a numerically controlled machine.The robot is servocontrolled by digital data and its suquence of movements can be changed with relative ease.As in NC machines, ther are two basic types of controls:point-to-point and continuous-path.
Point-to-point robots are easy to program and have a higher load-carrying capacity and larger work envelope,which is the maximum extent or reach of the robot hand or working tool in all directions.
Continuos-path robots hace greater accuracy than point-to-point robots,but they have lower load-carrying capacity.Advanced robots have a complex system of path control,enabling high-speed movements with great accuracy.
(Kalpakjian S.,Schmid S.R.,Manufacturing Engineering and Technology 5th edition,p. 1169)
Circular İnterpolation
The inputs required for the path are the coordinates of the end points, the coordinates of the center of the circle and its radius and the direction of the tool along the arc.
(Kalpakjian S.,Schmid S.R.,Manufacturing Engineering and Technology 5th edition,p. 1158)
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