A Novel Force Transducer and Load Cell Design Using 'Leaky' Electromagnetic Waves

摘要

A new technology lets you create high-performance load cells from virtually any material. Force transducers, which include load cells, accelerometers, and pressure sensors, have been designed, manufactured, and commercialized using tried-and-true methods for more than 50 years. Even with the advent of newer materials, electronics, miniaturization, and better design analysis, transducers are still designed and created in much the same way as they were many years ago. The design methodology, focusing on tradeoffs among cost, manufacturing, reliability, and performance, has prevented these sensors from expanding beyond the most obvious markets. Because of the relatively large engineering effort required, manufacturers are reluctant to spend money to develop novel transducers for new applications. However, reconsidering the design methodology and using new technologies opens up many new application opportunities, both within the traditional force transducer markets and in new, (so far) unconsidered ones. This article develops new load cell designs based on electromagnetic "leaky" waves. This technology lets us create high-performance load cells out of virtually any material, for a fraction of the cost of current designs. These can be mass produced without requiring tweaking, and can be fabricated, assembled, and tested without the need for manual labor. We start by explaining sensor operation and construction, along with manufacturing flow and system benefits, and we end by showing data for load cells constructed out of either aluminum or plastic (Delrin) and indicating the current state of commercial development.