An engineering brief
The train never has to stop for a station to work.
Passengers board and alight through a small, self-powered exchange carriage. It starts from rest on the platform, matches the train's speed from behind, and couples automatically at the rear — while the main train keeps running at constant speed, on schedule, the entire time.
Exchange carriage
Waiting at platform- speed
- 0 u/s
- gap to train rear
- 0 u
- cruise target
- 96 u/s (train: 70 u/s)
Main train
Never stops- speed
- 70 u/s (constant, never stops)
Why it holds up under scrutiny
Straight-line coupling
Coupling happens purely from behind, in 1D longitudinal alignment, using standard automatic couplers — no side-docking, roof-docking, or high-speed mechanical arms.
Wide timing margin
The catching carriage gets a long acceleration distance, so there is no split-second launch window — synchronization is gradual and forgiving.
Fail-safe abort
If synchronization fails, the carriage simply aborts, brakes on its own track, and tries again later. The main train is never endangered.
Independent emergency braking
If the main train performs an emergency stop, the carriage receives the signal and brakes independently on its own track.
Energy savings
Only the small exchange carriage's mass is fully stopped and re-accelerated at each station — the heavy main train keeps its kinetic energy, sharply cutting braking and re-acceleration losses.
Station-assisted launch
Linear motor sections in the station track can help accelerate the boarding carriage, reducing the propulsion required onboard.