[zalo]

Since the train only shakes side to side (and not up-down or forwards-backwards), you only really need spring dampening along one axis.

While you could set up a linear rail with some pretensioned bungie cables (similar to how the Hover Glide backpacks work), I’d recommend using parallel leaf springs as they’re lightweight, low-form factor, mechanically simple, and low stiffness.

Here are some links to 3D printed inspiration: https://www.thingiverse.com/thing:2574629 https://www.thingiverse.com/thing:4738960 https://www.thingiverse.com/thing:4411343

The key to supporting human weight is to replace the thin plastic leaf springs with sheet metal. You can also add more springs in parallel (increasing the weight it can support, but reducing the travel).

And some of my gifs of them in motion: https://imgur.com/a/YH4HQpo