•A lab test method to evaluate dynamic performances of track inspection wagons (TIWs) is proposed.•Dynamic performances of a new TIW are revealed through extensive measurements.•Safety of the new TIW under different rail misalignments and defects is validated.•The new TIW can withstand a certain degree of impacts due to track irregularities. A new type of track inspection wagons (TIWs) for damage detection in urban rail transit systems is proposed to overcome the problems existing in traditional track inspection and ensure efficient and safe detection. Research on the dynamic testing and evaluation of TIWs is inadequate, which is not conducive to the design and improvement of similar products. Considering this, extensive dynamic performance tests and safety assessments under different running speeds were carried out on a new intelligent TIW. In this study, the rail misalignment and harmonic defects were designed to simulate the local irregularities in actual track lines. The accelerations of the axle-box, frames, vision modules, and wheel–rail forces were measured and analysed. Since the vision modules are the most critical components in the inspection system, the experiments focused on the evaluation of the safety of the visual module subjected to various track impacts. The experimental results indicate that the new intelligent TIW shows outstanding dynamic performance in the lab tests. Within the normal working range of the vision module, the vision modules of the wagon can withstand certain impacts from local rail local irregularities owing to its suspension design. Rail harmonic irregularity has a higher impact on wagon vibration than rail misalignment irregularity.