A drop weight impact tester was used to determine the impact strength and stiffness of foams used in the Mercado®. Sheets of foams were placed under falling weights from various heights to determine the energy absorption ability under impact and resulting damage to foam.
Secondly, ultrasonic imaging equipment was used for detecting impact damage that can be invisible in foams. Foams were scanned after impact test to reveal any accumulated damage and the extent of the spread of damage.
Lastly, a specialized split-Hopkinson pressure bar was used for high speed compression testing of foams. Polymer foams show different strength and energy absorption capability at different rates of impact or compression. This equipment provides properties at high loading rates.