DISCLAIMER: I'm about to launch this as a free open-source project, built from available parts with only a drill press and one or two welds. Please contact me if you're interested to participate...
Hi,
I have been lurking around here for a long time, reading up on all the existing options for movement controllers and locomotion devices. Sitting down on a chair vs using an ODT seems to be a frustrating choice, full of compromises (immersion vs comfort vs price and space requirements...). Yesterday it occured to me that there might be an intuitive solution that is affordable for regular users...
I present you: the "LocoVR" (thanks for the name suggestion!)
It is basically a cross between a small bar stool and a kind of oversized joystick (small deflection [~10°], stiff and tilt resistant) with a swivelling top part (interchangeable for free 360° rotation or spring loaded incremental turning). The shaft is set to a length that allows your feet to barely touch the ground, supporting most of your weight in an upright position! You get on top of the seat with your hips behind the padded crossbar, turn around and lean slightly into the direction you want to move. The axial deflection itself is constrained to a relatively small and safe degree, while your upper body will tend to bend over naturally to gain additional inclination (stand up and take a moment to try and visualize this. Keep in mind that your weight will be supported!).
Advantages:
1) Shifting your balance will fool your vestibular system into thinking that you're actually moving . In this way (and by using the seat orientation as an input) it becomes possible to decouple looking and walking, just like with an omni-directional treadmill.
2) Since you're sitting erect, there is no disconnect between your avatar's view and your lowered position in a chair. I found this to be quite annoying and immersion-breaking, a major disadvantage of playing in a sitting position.
3) It's comfortable: I imagine that running around on a passive treadmill is great, but could actually discourage you from longer gaming sessions once the novelty wears off.
4) It's stowable: breaks down into 4 parts.
5) It's affordable: With good sourcing, it should cost around 100-150 Euro


The recessed end flange acts as a tilt resistant bearing (adjustable by the contact area) in order to support a stable neutral position under one's body weight.