As vehicles become more sophisticated so necessarily do the technologies that are used in testing them. Testing company Element Warren in Detroit US, for instance, is investing $5m in what it claims is a “unique electromagnetic sled”, as part of a strategy to become a world-class centre of excellence for seat structure and seat materials validation. According to William Mangum, business development associate at the company, the installation is an enhanced version of one that was previously built for a European OEM. “We are introducing a new multi-part carriage system into our design, which will allow us to match the carriage size to the part size and therefore achieve larger (higher G) pulses for smaller components,” he explains. 

Two key performance parameters for the installation are pulse matching and accuracy. The first of those refers to how closely the sled is able to recreate the acceleration and velocity output from a real-life crash event, which is termed the pulse, and the second to the ability of the sled to match the client’s target pulse in relation to acceleration and velocity. “The purpose of the sled is to recreate this pulse on test samples without crashing an actual vehicle,” states Mangum. “The higher the level of accuracy the better the test data, so for regulatory pulses such as Euro NCAP we are expecting the sled to be accurate to within +/- 0.1G.”

In use the sled is supported by physical guides and propelled by 18 electromagnets that allow for precise increases and decreases in input energy as the carriage moves down the track. A 6MW generator delivers the energy to the sled as needed. 

Smart systems for the dummy

Another feature of note is the dummy positioning system, an integral imaging measurement system that allows the measuring and recording of various locations of interest in vehicle coordinates or other parameters…