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Linking CNC Machine Tools to the Internet

The current state of technology for linking CNC machine tools to the Internet is not very state-of-the-art. Look at desktop PC or laptop and one will find that all kinds of gadgets are available to make it faster, simpler to use or more powerful. Operating systems that come out of Microsoft on a semi-regular basis are constantly adding more power to the laptop or desktop PC. Contrast this situation with that of CNC machine tools. Experts have been predicting that the Internet will be the next technological innovation to dramatically affect the machine tool industry.

Experts have been predicting that the Internet will be the next technological innovation to dramatically affect the machine tool industry. Products now being introduced into the market are giving glimpses of how this becomes reality.
Because the network was restricted mainly to the office area, CNC machine tools were stand-alone islands of productivity removed from other manufacturing information systems and processes. Networks that did make it to the shop floor were invariably terminated at PCs, which acted as crude file servers connected to the target CNC with an RS-232 link. According to its developers, the new network connection eliminates the need to drip feed large data files from a PC to the memory of a CNC and will bridge islands of productivity to networked manufacturing information systems and processes.
This network communications package, designed and developed using standard elements (Ethernet, TCP/IP and FTP), is flexible because it can be hooked up to different operating systems. This means it works in diverse network environments where UNIX workstations and PCs with DOS and Windows coexist. It increases productivity and efficiency by incorporating both an FTP server and FTP client.
The FTP server allows CAD/CAM engineers and operators to transmit files directly to the Ultimax CNC's hard disk drives while the machines are cutting. Jobs can be queued on the hard drives without the downtime associated with setting up serial ports for DNC. Ultimax machines equipped with UltiNet also can share files. Machinists can easily move files from one machine tool to another.
So the expensive, cutting-edge CNC machine tool comes with a paper tape reader, a 20 milli-amp Current Loop adapter and an RS-232 port all at no extra charge, but no one expects to buy a new PC or laptop with those capabilities. The PC or laptop will come with USB and Ethernet connectivity built in, yet the machine tool will not.
True, the newer CNC units are now offering an optional Ethernet port, but the majority of these controls are not set up to use even the basic potential of Ethernet connectivity. The current Windows 2000/XP/ME operating systems and all the older Windows NT/98/95 operating systems are designed for networking and connecting to the Internet right out of the box. For whatever reason, the control builders mostly offer products that seem to stop at their connection to the outside world. An optional Ethernet port that only allows to pulls a file from the network to store on a hard drive inside the machine is barely tapping the full capabilities of the Internet or of the company’s internal network.
With this network connection, files can be transferred between the Ultimax CNC and other networked equipment at Ethernet speeds. For example, ten megabyte files can be transferred in less than 40 seconds. (In comparison, transferring a file this large on a network communicating at only 9600 baud would take almost three hours.)
So now that the door to the Ethernet is open, what's next? The Internet. Web servers are the model for how the industry will view machines in the future and CNC performance, activity and health. Data that is public in the CNC's data dictionary will be transmitted across the Internet to clients who will format the information in a manner that is useful to the viewer. Spreadsheets and quality control software that use up-to-the-minute data can then provide relevant production statistics in near-real-time. UltiNet uses the same IP-addressing that is familiar to those on the Internet. With some minor rearrangement of equipment and software. What if the target machine reports that it's not available due to a failure? The manager will ask the machine what kind of failure. The machine will answer with an alarm message that indicates, for example, that the drawbar mechanism is not working correctly and that tool changes are impaired as a result. The shop manager will then send an e-mail message to the service company in the target machine's area and inform them that the machine's drawbar mechanism needs repair.
The service group will need more information so they will ask the machine to identify the problem. Is the air pressure okay? The machine will report that it has been consistently at 70 psi—well below the published specification. The service engineers will then call the site supervisor at the target machine's location to report that the air pressure to the machine appears to be below specifications. The supervisor will find that there's been a leak in the air line causing a drop in pressure to the machine. The shop is saved an expensive, unnecessary service call and the problem is resolved proactively.
While gathering information, the service engineers discover that the machine is a revision behind in executive software. The site supervisor is notified during the courtesy call on the air pressure. The machine is under warranty so the service engineer offers to send the new revision to the machine. The site supervisor has fixed the air pressure problem and now has the machine running an overnight, 10-hour job. The revised software is loading in the background so the next morning the site supervisor can reset the machine and the new revision will be in effect. Most of what is needed for this type of transaction is already in place.

Information Sharing On The Web
The Internet is available just about everywhere. At home, on the golf course and even on the beaches of Hawaii, you can log on and get information that is available on the Web. With a good Web-based system, you could view data with a standard Web browser from anywhere that one has access to the Internet. NC part programs that are developed in one facility can be downloaded directly to the CNC (or to its Web server), even if that CNC is halfway around the world. This is a nice feature for big manufacturers who concentrate their CAD/CAM work in one location and their manufacturing in another.
Other tempting possibilities with CNCs connected to the Internet have their allure. Internet connections will provide engineering with current tooling or material information, notify maintenance when alarms occur or machines go down, inform management of part-counts, send e-mails or pages to notify appropriate personnel as needed, and allow operators to inform engineering of the current status of the machine.

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