It could be as simple as a car with an infinite amount of track friction and a equation that detaches it from the tracks if too much force hits it. https://nolancompany.com/wp-content/uploads/CS-50-car-stops.jpg
https://nolancompany.com/car-stops/
#A deployable car stop to stop cuts of cars without needing to run to them.
blissful lake
A deployable car stop to stop cuts of cars without needing to run to them.
bitter wave
That would be pretty easy to make.
Just a custom car
That basically has the weight of the sun
And that’s the mesh
blazing vigil
Or just a vehicle with really good brakes