The device for impact tests serves to perform measurements of the acceleration of the test object in the event of a collision. The goal of the task is to design the construction of such a device and to verify its suitability from a dynamic point of view. The device operates according to the principle of free fall, where the tester is mounted on the carriage, which is then left to the free fall and impact between carriage and the pads, which turn the impact pulse signal into a half-sine signal. The resulting impact acceleration is measured by accelerometers, which are attached to the carriage. The device consists of a steel base, which serves as a inertial load, and a metal shaft attached to the base as a guiding tool for the controlled free fall of the carriage, all together holding the frame made of aluminium profiles. In the work, two iterations of structural improvement were carried out using the results of the modal analysis.