October 2020

30 n MACHINE BUILDING October 2020 www.drivesncontrols.com Automated lab upgrade delivers 800% productivity boost W ell plates are a key component in clinical laboratories where bioassays are used for high- throughput screening, and in vitro diagnostics (IVD). Reproducibility, precision and accuracy are vital to creating stable, reliable systems that allow clinicians to interpret the results correctly. To deliver high volumes of accurately filled assay containers, well plate kit manufacturers need dependable technologies. When one of the major players in the market for disease and allergy diagnostic assay kits began having problems with an ageing machine, it decided to upgrade its multichannel well- plate-filling system using the latest automation technologies. The existingmachine had been in service for 15 years and had started to experience issues that were affecting its productivity and efficiency. The machine was prone to overfilling the wells, causing spillages and, at one point, the manufacturer could only fill half of the 96 wells in a plate at a time. As a result, the process was being slowed down substantially and could deliver only 600 plates per day. The technology behind the machine was also obsolete and some replacement parts were no longer available, leaving the company exposed if the equipment failed. In addition, the system could no longer offer the level of flexibility that the plate-based assay provider needed to support its customers. For example, it did not offer automated plate-stacking, which had to be done by hand. Within each plate, all 96 wells had to be filled with the same liquid, making it impossible to dispense different substances accurately onto the same plate. To develop a new machine, the company approached Horizon Instruments, based in Heathfield, West Sussex, which has an expertise in designing and manufacturing instrumentation and automation equipment for the medical diagnostics, pharmaceutical and biotechnology sectors. The new design that Horizon came up with uses four servomotors to load empty well plates from a stack (input station) onto a walking beam transfer system, which moves towards the filling station. There, the plate is aligned with a movable nozzle head that connects each of the 96 wells with a filling nozzle and dispenses the required volume of liquid from a specific input bottle. Once the liquid dispensing is complete, the plates are transported to an output station and stacked on top of each other. Loading the well plates is achieved using four Mitsubishi Electric Melservo-JE servomotors and their associated amplifiers, which are linked via a high-speed, noise- immune SSCNET III/H fibre-based network. Speed and positioning are controlled by a Melsec-L PLC with a built-in motion control module. The system communicates with a GOT 2000 touchscreen HMI, via which operators can choose recipes and the liquid volumes – up to 250 microlitres – that need to be dispensed into the wells, as well as monitoring the process in real-time. If the system stops, the HMI provides information to help resolve the issue and restart the machine as quickly as possible. The newmachine has helped the IVD kit manufacturer to eliminate problems associated with overfilling, such as equipment downtime needed to clean the machine and its surroundings, at the same time as improving product quality. The company expects to reduce the waste it generates by at least 50%. The new machine can process 4,000 to 5,000 plates per day – up to eight times more than the previous system when it was working at full capacity. The new set-up is flexible enough to scale up and support future implementations. For example, it will be possible to install robot arms to load and unload stacks of well plates, or to collect samples for quality control purposes. n By upgrading to an automated well-plate filling machine, a supplier of immunoassay and diagnostic services, has boosted its production by up to 800%, and expects to halve its waste. It is achieving fast filling speeds, high accuracies and repeatability using a combination of servodrive, PLC and HMI technologies, linked by a high-speed fibre network. The automated well-plate-filling machine has boosted production yields by 700-800% and is expected to halve waste. Operators can select the recipes and monitor the process in real-time via a touchscreen HMI