A process trailer is a low-profile flatbed vehicle towed by another vehicle or driven independently on which actors, props, and camera equipment are mounted to simulate driving scenes. By placing the entire set piece on a moving platform, the camera operator can film actors appearing to drive or ride in a vehicle while maintaining full control of lighting, camera angles, and sound recording in conditions far more controlled than actual driving would allow.

The process trailer is a long-established practical production technique used in film and television to create convincing in-vehicle footage without the logistical and safety complications of filming inside a moving vehicle on a public road. The trailer typically carries the vehicle body, stripped of its mechanical drivetrain, along with camera rigs mounted at multiple positions around the shell. A camera car or tow vehicle pulls the trailer through a controlled environment while the camera operator films the actors from outside, through the windscreen, or from mounted positions inside the vehicle shell. Process trailers can also be driven on closed roads or lots at controlled speeds with a camera car running alongside. The technique allows for steady, well-lit, and cleanly recorded footage that is difficult or impossible to achieve with on-road documentary-style shooting. When combined with rear projection or digital compositing for the background, the process trailer creates seamless driving scenes entirely under production control.

AI video generation can simulate the visual result of process trailer footage by prompting for interior vehicle shots with dynamic backgrounds, controlled lighting on the subjects, and the characteristic framings of classic in-car cinematography. Describing "dashboard-level camera looking at driver," "interior car shot with passing scenery visible through windows," or similar framings communicates the aesthetic without requiring physical equipment.