Just what the doctor ordered

Automation is rapidly making its way into every industry and the medical sector is no different. With an aging population, heavily reliant on the medical sector and the thousands of medications prescribed annually, it is no wonder the industry is looking for better ways to organize and dispense pharmaceuticals. According the Kaiser Family Foundation, the number of retail prescription drugs filled at pharmacies last year totalled more than 4 billion in the U.S. alone.

The Rowa Vmax system automates pharmacy storage, sorting and dispensing of medication packages to pharmacists.

With space at a premium, especially in smaller, local pharmacies, only the most popular and necessary medications are kept on hand. Not having the correct prescription in stock can lead to health concerns for patients as well and economic challenges when customers decide to go elsewhere. Providing customers with the incorrect prescription, dose or an expired item can have fatal consequences.

To address these challenges, Rowa Technologies, a German-based division of medtech firm BD, has designed a range of pharmacy-oriented systems to automated drug delivery.

“We’ve been in the midst of the digital future for some time now,” explains Dirk Bockelmann, head of international sales at BD Rowa. “And from our perspective, it offers enormous potential for the pharmacy market.”

Often ordering in bulk, a pharmacist is required to manually sort, catalogue and shelve hundreds of bottles and boxes that arrive on a daily basis. With behind-the-counter shelving space at a premium, these boxes and bottles need to be arranged to maximize space and organized enough that a pharmacist can easily find it and dispense it to customers.

In larger chain pharmacies, pharmacists have quotas to dispense medication in a limited time to maximize customer retention. This added pressure could lead to mix ups and mistakes that can have dire consequences.

Recognizing these challenges, Rowa Engineers saw this as an opportunity to develop the Vmax pharmacy robot, designed to sort and store prescription medicines, as well as overstock, OTC medications, plastic-wrapped packages and refrigerated items. The OEM’s four different systems (Vmax 130, Vmax 160, Vmax 210 and Vmax 320) offer a number of different configurations and features to meet the needs of any pharmacy, no matter the size.

Rowa boasts the Vmax offers the optimal use of space, with up to 4,000 packages per running meter. Depending on the configuration, the system has the capability to store up to 56,000 packages in a compact footprint (the smallest Vmax measures 3.16m x 1.33m x 2.1m), but can be tailored to fit any back-end of a store. Inside the enclosure, the boxes/bottles are stored to maximize space and new packages can be added without having to reorganize existing stock. The system is able to recall the position of any item based on batch number and expiry date, optimizing the workflow.

When a shipment comes in, the pharmacist can place packages in the input station. For a fully automatic input, the system includes the ProLog/iProLog feature, which enables the user to dump a large number of packages into a bin with a conveyor that moves the packages to the unit’s robotic arm with gripper, where the package is measured, scanned – both barcode and expiry date – and input into the Vmax. This feature allows for lights-out operations of stock inventory, sorting approximately 120 packages per hour.

The Vmax comes with HD-Multi Picking head technology to ensure smooth and accurate transfer of up to six square, round and wrapped packages from the input stage to proper storage section. Upon request, the picking head can return a package to the output station in eight to 12 seconds. With a capacity of up to 56,000 packages, the picking head has its work cut out for it.

When designing this essential workhorse, Rowa engineers grappled with many considerations. The picking head, first and foremost, needed to be fast. The goal of the system is to speed up operations for optimized efficiency. The picking head needed to work faster than a human counterpart.

Another challenge for the team was designing the robotic arm so that it could move vertically, horizontally and toggle between two opposite shelves without dropping packages or bumping into the shelved packages.

The Rowa team was also concerned with ensuring cleanliness within the enclosure. Dealing with the medical industry, these highly sensitive products could not be introduced to contaminants. When it comes to designing medical systems, noise considerations are always taken into account, especially if this system located near customers, the system should not be loud or bulky.

To solve these challenges, the Rowa engineers looked to igus, a German-based company that provides complex technical polymer components.

“I got in contact with the chief engineer [at Rowa] and tried to convince him [to use] a new dryspin lead screw geometry,” explains Stefan Niermann, head of business unit – drylin linear & drive technology at igus. “We were able to promise him a better product than the current solution for even less money.”

The drylin high helix thread offers a ratio of diameter (14mm) to inclination (25mm) that ensures precise linear movement onto shelves. The Rowa engineers incorporated this custom igus product into the picking head to give it smooth horizontal movement, placing boxes and bottles onto the shelf, with speed and agility.

According to Niermann, the engineers were previously using a 12mm diameter lead screw but the new 14mm diameter provided longer lifetime and higher precision at a lower cost. And as the relationship progressed, igus demonstrated that the picking head could include an even longer lead screw due to this bigger diameter, making the system more configurable and allowing for more packages to be collected.

Another benefit of this product is the plastic nut. Rowa engineers opted for this igus product because it enables the system to operate with less than half the friction of competing parts with no lubrication needed, making it contaminant free and requiring little maintenance.

“When you compare ball screws with lead screws, lead screws are much cheaper and also make less noise,” Niermann adds. “They also need no lubrication if they are done from igus plastics. And any kind of noise is [problematic] in medical environments.” Rowa engineers boast that the picking head is extremely quiet with an average sound pressure level of Lp(m) 48.3 db (A).

The Vmax HD-Multi Picking head technology ensures smooth transfer of packages thanks to igus’ drylin high helix thread and plastic nut.

Beyond the drylin high helix thread and plastic nut system for the horizontal movement, igus also provided the drive components to meet these demands. Custom-made linear guides as well as energy chains to supply power were incorporated into these automatic machines.

Rowa required short working cycles and very tight bend radii on both side and order to achieve this, the company opted for pre-harnessed, ready-to-install “readychains” systems with chainflex cables. This provides the robotic arm with power to the motor that drives the lead screw allowing it to move gracefully throughout the enclosure.

Providing innovative solutions has enabled igus to expand their relationship with Rowa, providing additional products such as igus’ oil-free drylin W and drylin T linear guide systems for the Vmax attached features.

With all of these engineering considerations, Rowa was able to design a system tailored for small to large-sized pharmacies with necessary add-on features to make it easier for pharmacists and customers to get the care and medications they need.

“Service offerings make pharmacies more competitive nowadays,” explains Björn Schleheuser, Head of Sales for Central Europe at BD Rowa. “The focus should always be on offering the pharmacy customers the optimal solutions for their requirements.”

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www.igus.com