A World Without Wires?
The future is now for process monitoring via wireless instrumentation, while wireless process control looms.
Paul Thomas, Managing Editor
The general public has grown accustomed to wireless technology through the use of cell phones, wireless PDAs and WiFi-enabled computers. Meanwhile, pharmaceutical manufacturers are just beginning to dip their toes in the wireless waters. Only now are wireless technologies becoming practical and robust enough for adoption on shop floors and in warehouses.
But there is little consistency of equipment offerings. “Most vendors are utilizing a scattershot approach to target any and all industries showing interest in wireless,” says Jake Millette, an analyst with Venture Development Corp. (Natick, Mass.). “Pharma-specific trends or vendors concentrating only on this market have just not materialized yet.”
From the manufacturer’s perspective, validation and collecting and integrating wireless data with current IT systems are real concerns. Regulatory prodding and high-profile applications have ushered in the era of Radio frequency identification (RFID), a wireless application for product track and trace purposes. But for ambient monitoring or process monitoring in the plant, the wireless explosion has yet to materialize. For process control, adoption is much further off.
In 2004, the pharmaceutical industry made up just 4.3% of total purchases in the as-of-yet small — $154.1 million — market for wireless monitoring and control products in discrete and process manufacturing, according to Venture Development. However, that figure is expected to increase to 5.1% of a total $419.3 million market in 2007, and rise measurably thereafter.
“We’ll see an accelerated acceptance of wireless in the pharmaceutical industry,” says Frank Williams, VP of Elpro Technologies (Brisbane, Australia), a provider of wireless modems, I/Os and other devices. Elpro specializes in monitoring valves, remote temperatures and tank levels, and has done applications with Merck, Pfizer, Pharmacia and Roche, Williams says. “There’s always a gestation period that must occur with new technology,” he adds, but more aggressive manufacturers are truncating the typical two- or three-year implementation cycle to 18 months.
“We’re not really doing anything with wireless right now,” says one pharmaceutical process control specialist. “But I see us making the leap to wireless fairly soon, probably for monitoring remote areas for materials storage.”A hodge-podge of pharma applications
Indeed, for remote storage areas and large warehouses where wiring is difficult and “line of sight” is easy, wireless makes sense, especially for ambient temperature and humidity monitoring.
But wireless sensors can also keep close tabs on pharmaceutical processes, particularly those that involve rotating or mobile equipment. And as the industry moves toward modular construction and nimble manufacturing practices, ready-to-move wireless equipment will gain more appeal. Wireless technology will enable many process analytical technologies, and dovetail nicely with FDA’s PAT initiative.
Manufacturers are experimenting with unique in-process uses, and vendors are diversifying their products:
The need for networks
- Abbott Laboratories suspected that an accumulation table on one of its packaging lines was causing slight damage to bottles and vials. Abbott sent samples of the containers to Sensor Wireless, Inc. (Charlottetown, P.E., Canada), which made an acrylic replica embedded with tiny accelerometers on a circuitboard. Abbott ran the replica through its bottling line, and took readings using handheld devices to measure the impact of bottles jostling against one another. Abbott used the data to adjust its line speed and correct the problem, says Tammy Wall, Sensor Wireless’s VP of operations.
- Mathis Instruments (Fredericton, N.B., Canada) recently unveiled a wireless version of its thermal effusivity sensor for monitoring powder blend uniformity. AstraZeneca studies showed that the sensor could operate reliably transmitting up to 50 feet and through three different walls, says company president Nancy Mathis. Mathis envisions that companies will use the device for process control as well as monitoring — stopping a blend when the end point has been determined, for instance. “The control stuff is there in terms of our capabilities,” she says. “But it’s not quite there for users’ readiness.” Companies need time to come to trust wireless sensors and measure them against other control devices, she says.
- Accutech (Hudson, Mass.) markets a wireless ultrasonic sensor for clean-in-place monitoring. The sensor resides on the outside wall of a vessel, and creates an “ultrasonic signature pattern” of the interior that indicates whether cleaning has been done properly. The company also makes a self-contained temperature probe that is mounted on rotating dryers for measuring batch temperatures, which can then be correlated to the dryness of the cake inside. It also has a line of wireless sensors to monitor safety showers and eye-wash stations.
- Honeywell offers a light-induced fluorescence sensor that mounts on rotating blenders, and has installed 17 units at various drug facilities, says Ted Dimm, Honeywell business director. The sensor measures the degree of fluorescent light emanating from a blend to determine when mixing is complete.
Sensors are typically deployed as individual nodes that transmit point-to-point with radio receivers, often linked to company PCs or PLCs. Many sensors are battery-powered and self-transmitting, though the most cost-effective means for wireless transmission is through wireless I/O devices and modems rather than through all-in-one devices.
Entire networks of similar or dissimilar devices all transmitting to one or a few antennae are the holy grail. This would allow not only for the easy collection of data and more centralized process monitoring, but also for additional sensors and applications to be installed on an as-needed basis.