“The engineering challenges that designers of these systems face start with the size restrictions and compact size of the devices,” says Lostetter. “Power usage is also important as more devices are moving to batteries, or batteries in part-time usage, and there is a requirement for systems that are efficient from an electrical usage standpoint. The size of the battery itself also becomes an important consideration and needs to be specified within the symmetry of the final device design and usage of the device.”
Accuracy and performance within a small package is a major challenge and design goal. Operation has to be highly accurate and precise, especially in dosing applications where there is a concern for patient safety and the potential for overdoses. Systems used in surgical applications often reflect the need for highly accurate motion performance, excellent feedback, and optimized speed and position.
The overall product strategy and concept for development is to work within the existing suite of technology solutions to design customized solutions for specific devices. As much as possible, existing products that offer high performance, small footprints, and energy efficiency are used to keep costs down. The subassembly itself may be highly specialized, but the heart of the product components used in the design is already a fit for these types of applications. Ongoing development on the motion building blocks themselves is part of the process of creating more potent solutions.
One trend is the use of micro motion solutions in dosing applications, such as push pumps and dosing pumps, with the push to smaller designs that deliver more precise movements and provide better energy management. It is also important to provide feedback on where they have moved and how far they have moved. We are seeing more lead screw and linear applications.
Lostetter says there has been high interest and questions about piezo technology. Compared to other motor technology solutions, piezo technology offers the potential for small, powerful systems, which provide high performance in a very small package. Movements are highly accurate, and the technology has improved its ability to provide energy-efficient operation.
“For medical device manufacturers, the ability to develop four to five different subassemblies from trusted technology suppliers enables them to use contract manufacturing that often specialize in biomedical products to do the final assembly and packaging,” says Lostetter. “It provides a complete design strategy where they have found that working with suppliers on subassemblies makes it possible to simplify the final assembly.”