Fantastic idea! Requesting Dorfing, whether as Clinician or Patient is debatable.
GChris the dwarf has long been obsessed with the workings of minecarts, carrying things in minecarts, riding in minecarts, and hitting things with very fast minecarts, which may also throw things out of the carts. He claims to be a discoverer of a radical new "Projectile Therapy" by which a dwarf can undergo a transformative experience when riding a quickly-moving minecart that suddenly comes to a halt.
He claims that a dwarf who achieves flight experiences an entirely different type of life as a "parabolic projectile entity" (words he almost certainly made up) and only transforms back into a creature on landing or making impact into a solid object. He points to
an ancient example where dwarves were thrown through fortifications using minecarts.
He proposes the following Sanitary Ballistic Treatment Room design: ("It's Sanitary because it involves water!")
(side view)
░ ╬C ////C☺↓
░~~~~~~~~~▲░░_______↑
░ = solid rock, ~ = 5/7 water, ▲ = ramp with 5/7 water, ╬ = fortification, C = minecart on a track, / = impulse ramp, ☺ = patient, _ = floor, ↑↓ = stairs
The treatment room works as follows:
1. The right cart marker is the location of a route stop, with the cart assigned to Ride Left Always.
2. A dwarf will place the cart there, and ride it left immediately.
3. The cart will rapidly be accelerated by the four impulse ramps. (I think four is enough.)
4. The cart goes airborne over the empty space.
5. The cart strikes the stationary cart, ejecting its rider, who temporarily transforms into a projectile.
6. The projectile/dwarf flies left and down into the 5/7 water, hopefully not dying on the first try.
7. Free swimming training! As the dwarf swims back to the ramp to climb out of the water.
8. The dwarf picks the cart back up and repeats the process.
The left cart will never move, it just serves to stop the moving cart. The room can be built in-plane, except for an exit next to the ramp , so a dwarf can climb out and walk around the fortification to retrieve the cart.
The reason a stationary cart is used to stop the moving one is so that the contents aren't teleported upwards. This idea would work with just a wall as the impact target, making sure there's open space overhead, and moving the landing area up one z-level.