Automatic driving vehicle and collision accident detection method and system thereof

The invention provides an automatic driving vehicle and a collision accident detection method and system thereof, and belongs to the technical field of automatic driving. The collision accident detection method comprises the steps that the current running state of a vehicle is determined according to the vehicle speed, the accelerator opening degree and the braking deceleration at the current moment, and the running state of the vehicle comprises at least one of the acceleration state, the deceleration state and the emergency brake stopping state; a pre-established vehicle body longitudinal acceleration calculation model corresponding to the current vehicle running state and data required by the model are utilized to calculate an expected value of the vehicle body longitudinal acceleration at the current moment; and comparing the expected value of the vehicle body longitudinal acceleration at the current moment with the actual value of the vehicle body longitudinal acceleration at the current moment, and judg