A platform for your bicycle trainer. Enables some tilt and fore-aft movement to make indoor training a bit more comfortable. May also help reduce stress on your bike. I used a four point of contact system. One each for the weight bearing points under the trainer, and one for the front wheel. I use two tennis balls in each of the front and back tracks. This restricts fore-aft movement but also makes it more stiff front to back so it doesn't rock front to back. I'm mostly looking for lateral rocking.

Print 8 tracks.

Cut your top and bottom platforms to fit your trainer/bike. I used 1/2 inch plywood. Finish as desired.

Screw or bolt the tracks to the platforms.

Ride.

I enjoy Zwift for indoor training. You might also like TrainerRoad, or RoadGrandTours.

My blog if you are interested.