Well, what do we actually have here?
- Unsupported hand grips
- Thumb-knobs that move:
- Dual sheathed cables
- Some kind of rotating accuators housed in a bolt-on housing.
At the head
of each handgrip is a thumb-knob with a lobe opposite the cables
. The grip is not twisted, but held in the hand: the knob at the head
of the grip is positioned with the thumb, which pushes/pulls the twin cables
and will affect a change in the accuator body: a rotation of some kind inside that housing.
The relatively low pressure a thumb would be able to exert suggests that the accuators simply position something without the need to overcome much resistance. The cables may be spring-loaded to return to a default position (like an outboard
throttle), or not, which suggests that whatever is to be adjusted with one's thumbs would be either left in the chosen position or constantly adjusted (which is suggested by the design: one has to hold the grips in one's hands, which indicates the operator is "hands-on" all the time, rather than occasionally twisting knobs on a console. When one is using this control, it demands your attention, like the operator of a radio-controlled toy airplane constantly adjusting elevator & aileron controls).
And there's one for each hand.
As to what it is actually designed to do is anyone's guess. The seller seems to think they have something to do with boats.
has a good hunch. I'm agreeing with him: though I don't actually see any splines, it's obvious that the end result is rotation in the center of those housings.
There is a "Ask the Seller a Question" link at the bottom of the page. Anyone brave enough?