This paper describes a linear acceleration sled device developed to study child responses to panic braking environments. A sled with a vehicle seat and soft simulated dash is accelerated by a drop weight in a similar fashion to actual vehicle decelerations when panic braking.A simple, two degree of freedom analytical model of the experimental device was developed to predict the dynamic performance of the sled and examine the sensitivity of various parameters in producing acceleration time histories of actual braking vehicles. This includes the study of drop weight size, drop weight distance, cable size, initial cable pretensioning and sled braking levels. A simple, two degree of freedom analytical model was also examined to simulate a child dummy sitting on the sled seat and verified by using actual sled acceleration-time pulses. The model was based on previously conducted vehicle braking tests with dummies and child dummy tests conducted on the linear acceleration sled device. Some of the parameters examined for dummy motion sensitivity were sled acceleration levels, sled acceleration duration, initial child position, seat surface friction, seat angle and child model joint stiffness.