One of the earliest full-fledged flexible manufacturing systems was developed by the Sunstrand Corporation in 1965. It involved eight NC machine tools with a computer automated roller conveyor.
US-3596673-A - Automatic Transfer Apparatus - Grant Date: 1971-08-02
Automatic device for delivering a calibrated quantity of a liquid from a first receptacle into a second receptacle by positioning a duct into the liquid to be delivered, aspirating the liquid into the duct for delivery into the second receptacle including control means cooperating with detectors of the position of the duct in the liquid and the aspirating duct.
Parent Company: F Hoffmann La Roche AG
Original Assignee: Hoffmann-la Roche Inc
Current Assignee: F Hoffmann La Roche AG
https://portal.unifiedpatents.com/patents/patent/US-3596673-A
U.S. Pat. No. 5,216,613
This invention relates to automated assembly lines and, in particular, to computer controlled and operated automated assembly lines. More particularly, the invention relates to methods for the real time asynchronous operation of a computer controlled and operated automated assembly line.
The invention is widely useful for the computer control and operation of automated assembly lines. One such assembly line in which the present invention has been successfully utilized is described in copending patent application Ser. No. 845,733, filed Jul. 29, 1969 now U.S. Pat. No. 3,765,763 by James L. Nygaard for AUTOMATIC SLICE PROCESSING. This particular assembly line is for the manufacturing of semiconductor circuits and devices. Application Ser. No. 845,733 is hereby incorporated by reference. Other lines in which the present invention is useful include automobile manufacturing assembly lines, engine manufacturing assembly lines, tire manufacturing assembly lines, railroad operation and control, etc..
https://patents.justia.com/patent/6467605
Advances in Hardware and Software mean Today's Flexible Automation Systems Can Handle a Wide Array of Manufacturing Tasks with Few Configuration Changes and Little Downtime.
Mechanical Engineering. Apr 1998, 120(04): 70-72
https://doi.org/10.1115/1.1998-APR-5
https://asmedigitalcollection.asme.org/memagazineselect/article/120/04/70/367688/Flexible-Automation-on-the-LineAdvances-in
For years now, industry has successfully implemented computer-driven, flexibly automated manufacturing systems. These systems are small in both size (the number of devices under computer coordination) and scope. They are typically confined to a single part family or a few similar ones, so there is a restricted part flow within the system.
Hardware Expands Options
Several advances in hardware have helped make flexible automation systems feasible and affordable. The most significant advance is the fast, inexpensive microprocessor. Just five years ago, a system with a 20-megahertz processor and 100 megabytes of storage was considered powerful; but now even the lowest-cost personal computer offers much more. The items costing $ 5 ,000 today were costing $100,000 10 years ago.
Another boon to flexible automation has been the advent of more-sophisticated robot arms and manipulators. Early robot arms had almost no adaptability, and they were very ' difficult to maintain. Furthermore, programming was comparatively primitive, requiring an interface through a means like punch cards. By contrast, today's robot arms are much more dependable because they are driven by more-reliable electric servo drives. Encoders keep track of positioning, enabling the end effector to be positioned precisely and consistently. Users can interface directly with the robot through a control pad or computer terminal.
Flexible automation also has been aided by the advances in mechanical devices. Years ago, most automation solutions required a custom-built machine with parts and attachments that had to be custom- machined by the manufacturer or the user; as a result, the design and construction of an appropriate device was relatively expensive. Today, many vendors sell equipment such as linear actuators, ball-screw drives, and belt drives, so a staff with technical training can put together a basic automation solution fairly easily. Even the most complex machines and configurations are far less expensive than they were just a few years ago.
Several software advances also have made reprogramming much simpler and quicker. Traditional programming has been done at a motion level-a device like a robot would have its task specified by a series of motions. Device programming is now migrating to a task level. For example, instead of a programmer telling a robot to move from point A to point B to point C, an operator would just give one command telling it to move along the length of the piece. Contained within the software is the built-in intelligence to interpret this move command correctly.
There is more of emulation versus simulation. Rather than having to write code, users now have the ability to characterize the behavior of the process through a series of pull-down menus. GM Nameplate Inc. in San Jose, Calif., uses robots to spray-paint parts for a uniform coating of specified thickness. To do the task, a large number of variables must be taken into account. In the past, the programmer would have to specify air-line pressure, atomizer pressure, paint-flow rate, and nozzle speed and direction.
By contrast, control software today is evolving into a form of expert system. Based on empirical data, GM Nameplate's system learns how paint quality responds to particular variables. Eventually, enough data are in the central data bank for the software to perform actual behavioral analysis. Once this knowledge base has been built, all the programmer needs to do is specify paint thickness, which is what the company is concerned about in the first place. The software will then use its built-in knowledge base to write the appropriate control algorithm. An algorithm for each new part or thickness can be developed within minutes. GM Nameplate uses five-axis machines that typically paint 20 different parts. In a new model year, the company would have needed to write 20 new programs; now it just plugs in 20 new shapes and coating thicknesses.
The interaction between automation systems and computer- aided design systems is also increasing. Given a set of instructions in the traditional way, a computer has no real knowledge of the size or shape of the part it is working on; it just knows that it needs to move the tool along a prescribed path. Interfacing with a CAD system is another shortcut that spares programmers from having to write code. By importing the object geometry from a CAD system, software can automatically write positioning code and process code to achieve the result specified. Systems can handle either two- or three-dimensional drawings. Some companies are evaluating the possibility of simplifying the process even further by configuring software to work with an image from a digital camera instead of a CAD package.
Whereas traditional automation systems handled one part at a time, new technology has made it feasible to handle batches of the same part. There are systems under development to identify and work on effectively even if every part is different. Genesis Systems Inc. in Davenport, Iowa, is developing a system that identifies parts in real time using a bar code or magnetic tag. As a part moves down the line, vision devices automatically identify the tag. Contained in the system is a database that specifies the proper control program for a part with that tag. By the time the part makes it to the tool, that tool is ready to perform the appropriate operations on it.
A part cannot be positioned exactly the same way every time. Hence, the vision system may not always be able to identify it. Such part-identification systems have improved enormously in recent years, and many can handle position deviations. Furthermore, the software can be configured to adjust the program slightly to account for minor deviations in position.
Eventually, operator intervention will not be needed in the reprogramming process. Information about a particular part won't even need to be stored in the database, because all the information about a particular part will be taken solely from the vision system. The system will look at the part and write the control program on the spot. Theoretically, the system can then work on any part, as long as the part's dimensions are within the range that the hardware can handle.
2000 Article
Flexible Automation
2017
https://www.assemblymag.com/articles/93979-fixed-vs-flexible-automation-systems
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