BDM 227 research

I'd like to make an animation which has 3D background and 2D character.
examples like:

https://vimeo.com/85933213

Some advise from CG Talk as Convert your 2D character into a rendered image sequence. Create a plane that is the same size as the rendered image. Apply a material to the plane. Then apply a texture to the material. Change the texture type to image sequence and browse to your rendered 2D output. Now you have a "card" that you can place anywhere in the 3D scene. You may want to add a constraint to the card called "TrackTo". This is how you make the card always face the camera.

At this point you could place the card inside a vehicle and parent the card to the vehicle. Then when you move/animate the vehicle the driver will remain with it.