This seat puts the quadriplegic sailor in front of the traveler, in seat that is fixed in the center of the boat, but can rotate around a cylinder in the base to keep the skipper upright when the boat heels. The seat is mounted on a large board that drops in on the cockpit floor, and is secured in the front using the lifting strap access hole, and in the rear by two posts secured to the traveler. The gimbal action is controlled manually using lines at the rear of the seat. The skipper is “trimmed” to the boat heel by the main trimmer from behind the traveler.
Because this seat is sitting on the cockpit floor, it provides more headroom for the skipper under the boom, when compared to the Sonar Mid-Boat Seat (which sits on the cockpit benches).
The photo below shows the back edge of the board that the seat is mounted on, cut away to fit on either side of the barney post. You can see the vertical aluminum posts on either side, which secure the board against the traveler. And the red lines that run to a cleat on either side control the angle of heel of the seat — uncleat one side and pull the other side to rotate the seat, approximately 45 degrees from lock to lock.
A brief video to demonstrate the seat motion: