Group 4 – Two Trax™

Typically, dynamic stress testing is conducted using a Split Hopkinson Pressure Bar (SHPB), where a stress wave is generated and measured by bars that strike each other. However, testing at intermediate to low strain rates with an SHPB requires impractically long bars, often hundreds of feet, creating challenges in terms of space, cost, and maintenance. To address these constraints, Two Trax™ presents the 'millipede bar' testing system—an innovative approach that uses bend junctions to allow the bars to fold within a compact space, maintaining the necessary length for intermediate and low-strain rate testing without the large footprint. This design allows for a more versatile, costeffective solution that can be implemented in environments with limited space. Our Hedgehog Concept focuses on maximizing testing efficiency while minimizing physical space requirements. The millipede bar system represents a breakthrough in engineering, utilizing a unique combination of bend junctions and compact architecture to transform the SHPB into a scalable, portable tool. Unlike traditional SHPB systems, our design significantly reduces both the cost of construction and maintenance, offering a streamlined, cost-effective solution without sacrificing testing capability. By integrating bend junctions into the bars, we eliminate the need for enormous physical setups, making the system both functional and resource efficient. This innovation opens the door for dynamic stress testing in a variety of settings, from smaller labs to remote field applications, making high-quality testing accessible to a broader range of industries.