Complex sentence: A crash test dummy embedded with a suite of sensors was placed inside the test vehicle to record acceleration loads and forces at the crew seat, while the remaining six seats were loaded with weights to simulate full-passenger-load weight.
Split into simpler sentences: A crash test dummy was placed inside the test vehicle to record acceleration loads and forces at the crew seat. One of the seven seats on-board was loaded with an anthropomorphic test device embedded with a suite of sensors, while the remaining six seats were loaded with weights to simulate full-passenger-load weight.