Wireless technology, having enjoyed tremendous growth via cellular phones and pagers, now reaches virtually any location. As might be expected, it has entered the realm of industrial computing as well. This means factory networks can escape the physical bounds of hard-wired infrastructures. Employees are free to roam unrestricted throughout the shop, and they are able to access the company network from any point.
Why wireless? Wireless technology can eliminate one more inefficiency in the data collection process. Many existing applications require the worker to leave the work area to provide timely input using a networked computer. This additional overhead expense and loss of productivity can be avoided using wireless devices, which allow workers to stay focused on their work.
Access To The Network
Wired networks are widely used in plants and are especially important for gathering and synchronizing data and statistics into shop management systems. Today, the integration of wireless nodes into existing wired networks or Internet infrastructures adds collection and monitoring capabilities without adding more computers or extending wiring systems. Figure 1 shows how wireless technology fits into a networked communications environment. Although wireless technology has been available for several years, it is not yet widely deployed in job shops.
For many shop owners, any technology that brings plant information into the office—on a timelier basis—can’t come soon enough. Local area networks brought shop data collection to the masses during the ’90s, and untethered devices and intranets have expanded those capabilities. Now, wireless technology is poised to advance shop management’s ability to control and monitor shop events as they occur. Wireless technology (or simply “wireless”) is a flexible technology that empowers various handheld and portable devices by the easy addition of wireless nodes to a network. Wireless is another tool in your technological tool kit. It’s fast, immediate and presents a real-time picture of shop events.
For most applications, wireless can add a significant degree of independence in a shop’s operation. Workers will access part and process specifications from locations where wired networks are impractical. Wireless connections can connect maintenance people with problematic equipment immediately. Wireless scanners connected to the main inventory database will quickly inventory and verify warehoused stocks.
Goals And Issues
When considering the use of wireless technology, the three major areas of benefit are no different from other business investments:
- If you can streamline communications between the plant floor and your plant management system, you can reduce costs. Eliminating manual data entry is a good example.
- Wireless technology can increase employee productivity. Does your current setup require a shop supervisor or maintenance person to go to the nearest networked computer to enter data or query the shop management system? If so, a wireless capability will increase employee productivity.
- Most shop improvements are undertaken to improve business efficiency. Wireless can expand upon the efficiencies already accruing from a plant network as employees become more productive.
The ability of wireless technology to improve operator/machine interaction addresses all three of these issues. Shops get closer to these goals whenever they connect the business systems and the people that can benefit from immediate feedback with machines on the shop floor.
Data Collection On The Move
Notebook computers, handheld PDAs (Personal Data Assistants) and tablet computers bring freedom of movement into the shop environment. They are untethered from the shop management system, operating as either untethered batch or untethered wireless devices. Both approaches are effective and have their place.
The mobility of portable products brought convenience to data capture anywhere in the shop, which could be batch-uploaded to the computer. Non-wireless handhelds empowered people on the plant floor for activities other than note taking and inventory. Wireless technology presents an option for bypassing the need for batch processing.
Vendor support for handheld devices in the plant grew, for they were more convenient than tethered network computers. Today shops have the ability to leverage existing software for the plant, using untethered devices.
Two years ago, some Henning Software customers began using an inexpensive, untethered, Palm-operating-system-based and Pocket PC PDA devices in conjunction with a barcode scanner and wireless card from Symbol Technologies Inc. The integrated PDA with barcode gun reads barcodes and accepts data input. It interfaces with a variety of shop applications from physical inventory, quality control, shipping, incident reporting, customer relations management (CRM) systems and other data collection activities. The bar code not only picks up product identification information and quantities, but it also supports recording textual data. Appropriate comments need not be scribbled on a note pad. Users can upload the batch information at any plant floor or office computer.
This capability also gave anyone using a portable or handheld device the ability to identify all the materials that were used or issued to a job. They then had the choice of uploading it later, or to quickly and synchronously make it available on any desktop screen in the inventory system.
Initially an untethered process, it is now also an untethered wireless feature in this system. Customers choose which is appropriate for their operation.
Tethered access: The essential issue for most shops is efficiency. The traditional approach throughout the 1990s was to bring computer access to shop workers, by placing hard-wired devices at important locations on the shop floor. Efficiency increases were due to increased timeliness and more convenience. Tethered access still inconvenienced supervisors, setup and repair staffs, or QA personnel moving around the plant.
Untethered access: As noted earlier, handheld devices, notebook or tablet computers, and barcode readers satisfy this need. The untethered device is not limited to the factory. It can be used outside the shipping dock or in the yard, where access to decision-aiding data can be valuable. Tether-free access to a plant’s data relies on a batch interface. The user is free to roam the plant gathering data and reading barcodes, uploading the data later, where it is synchronized with the existing databases.
Synchronization involves integrating the collected data into the existing computer system, something the software vendor would typically undertake to maintain the integrity of the database.
Wireless, untethered access: As each new technology emerges, shops frequently identify unsatisfied needs. And thus, tether-free, wireless devices are an alternative that is quite supportive of an efficient, uninterrupted workflow. Collected data can be synchronized in real-time with the computer applications, resulting in efficiencies from timeliness and convenience.
Today, shops and vendors that have taken the first step toward untethered data collection are well positioned to jump to the untethered wireless arena by simply adding wireless access points
It is important that the wireless interface be one that people will use. It would be especially useful if it were the same interface or a subset of the interfaces with which they are already familiar, such as the same screens for desktop software.
Wireless notebook computers and tablet PCs immediately can be used with any application, for they can present the same desktop screen images. To use handheld devices and their smaller screens, the application vendor will have to support the reduced screen size. It is not practical to use existing applications designed for a typical PC screen on the miniature screen of a handheld device, which has half the number of imaging elements for creating text and images. Many software vendors have already modified their applications to accommodate both large and small screen formats.
The Wireless Shop
Imagine this picture of your wireless shop: In the morning, using your shop management software’s scheduling module, your scheduler opens, assigns or reassigns operators and equipment according to the priorities and material availability. Wireless doesn’t change that basic process. Completion of the schedule, however, effects the creation of a new database for access by wireless devices. This database contains everything that can be seen or manipulated from a traditional desktop computer—but employees do it from their current location, without having to locate a networked computer.
Later, on the plant floor, the shop supervisor can use a handheld, wireless device to scan bar codes on a finished part at a machine, key in the number of completed parts, and simultaneously check the scheduling database to determine if the job is running smoothly. Was the job scheduled for noon completion? Does the number of completed parts suggest that the operator is way ahead of schedule—or behind schedule? Supervisors can immediately adjust the schedule, able to ascertain on a handheld the priorities of other in-process work, as well as those jobs ready to begin.
When production quantities and efficiencies are only understood at the end of a shift, the opportunity for real-time changes necessary to improve efficiencies is lost.
Adding Wireless Capabilities
Considering wireless technology for the sake of adding new technology won’t necessarily add business value. If your computer system has an efficient network with wired-in workstations in the shop, you may decide to leave it alone. If you need additional capabilities, it is simple and inexpensive to add a wireless node to the network or plant Intranet. The ideal combination of tethered and untethered data collection is a hybrid situation: Use the wire where wire exists and makes sense, and use wireless where it adds value.
When you can identify a situation where adding wireless capability offers access to up-to-the-minute information workers need, while retaining their flexibility to move around the shop floor, then it is easy to justify wireless applications in terms of increasing shop efficiency and employee productivity.
Wireless access points typically can be added to existing networks as simply as adding another node. In reality, job shops need neither to redefine their entire communications network, nor to buy all new equipment. Shops that have installed a backbone network during the last 5 to 10 years will find that network more than adequate to support subsequent hardware upgrades and still have bandwidth to spare.
Depending on the shop layout and network architecture, adding wireless can be as simple as tapping in a couple of access points at strategically chosen locations in existing lines without any changes to the remaining network.
Be aware that wireless operations can increase your security exposure. Use the encryption capabilities built into the wireless devices. If you don’t use these available features, your wireless communications could be intercepted.
A Virtual Private Network (VPN) is one method used to enable the secure transfer of data from a remote client to a private enterprise server. A VPN can be defined as an on-demand connection between two computers in different locations, plus a route, or tunnel, over a public or private network. It is TCP/IP-based and is used to provide secure, on-demand communications by using dial-up lines, local area networks, wide area networks or the Internet. To ensure privacy and secure communication, data transmitted between the two computers is encrypted by the Point-to-Point Protocol (PPP).
Improving Shop Efficiency
One direct impact from adding wireless capabilities to your shop network is the immediacy of data availability. You will no longer have to wait until the end of a shift to review shop efficiency or check job progress against the schedule.
The second direct impact of those wireless capabilities is realized by people on the shop floor. A wireless capability untethers people and gives them the opportunity to be more efficient in the performance of their duties.
From a business perspective, efficiency and productivity are important. For employees, convenience and an improved ability to accomplish a job with fewer interruptions are benefits. Implemented properly, wireless operations can improve employee job satisfaction.
Use wireless to increase the interaction between people and machines, so both can work more efficiently. Increased business efficiency will follow naturally.
About the author: Rich Henning is president of Henning Industrial Software, Inc., in Hudson, Ohio. He can be reached by e-mail at firstname.lastname@example.org.