A system comprises a computer having a processor and a memory, the memory storing instructions executable by the processor to access sensor data of a sensor of a vehicle while an adaptive cruise control feature of the vehicle is active, detect, based on the sensor data, an object located along a path of travel of the vehicle, determine that the object is a moveable object based on a radar return of a radar reflector of the object, and responsive to the determination that the object is the moveable object, adjust, by the adaptive cruise control feature, the speed of the vehicle.