The Mannfit system is a new approach to physical fitness based on integral kinematics.
A simple implementation consists of a destabilization bar together with an Android or IOS app (or Meta Spaceglass app), which can be taken to market or distributed freely.
The fitness bar has a mounting bracket to which the user affixes a smartphone running the Mannfit app.
The Mannfit system concerns itself with not just differential kinematics (distance, speed, acceleration, etc.) but also with integral kinematics, e.g. absement, absity, abseleration, etc., and also absangle (integration of angle).
See for example: http://wearcam.org/mannfit/IEEE_GEM2014_MannEtal_pages270-272.pdf
A ball valve is a valve that controls the flow of water using a ball that
has a hole drilled through the ball. When the ball is turned so the hole is
at a right angle (90 degrees) from the flow pipe,
the water is shut off, as shown leftmost below:
When the ball is turned so the hole runs along the pipe, the valve is turned on, as shown rightmost above.
Here is a typical ball valve, shown in the closed position leftmost,
and in a partially open position center and rightmost:
I attached a long metal bar to the ball valve, together with a flow sensor
or virtual flow sensor (e.g. tilt sensor), as shown below:
Doing exercises like pullups, dips, leg raises, etc., from the bar
creates an absemental fluid flow metaphor:
Metaphor: bucket that fills when you tilt away from straight. Stop filling (a real or virtual bucket) by stoping the tipping.
Easy metaphor to understand.
Reality: water (or green slime) that drips on your head if you don't stay straight (closed).
Ball valve metaphor and reality: straight across = closed; tip = open some.
Angle straight across = 0.
Tipping angle, distance angle (absolute angle), and its integral ("anglement") is thus the amount of water in the bucket (virtual) or amount of green slime on your head (real).
A camera phone uses computer vision to measure or sense each repetition of a periodic exercise, and "clears" the virtual bucket after each repetition. The user attempts to stabilize the bar, thus "spilling" the least water.
Alternatively the metaphor (or reality) is that of air flow into an inflatible toy. Tilting the bar inflates the toy's belly, giving the toy a fat belly. The goal is to keep the toy slender (not fat) by holding the bar straight (level) while performing the exercises (pullups, dips, leg-raises, etc.).
Meta Spaceglass provides also an alternative embodiment of the product.