Cyclogyro , paddlewheel rotors .... various names ....
I built one of those in my basement in 1980. The rotors were 2 feet long , cord 4 inches , symetrical (they have to be) and the diameter of the rotor assembly was 4 feet.
I used a one horsepower electric gearhead motor on a rehostat , which means I could control the electric motor rpm from 0 to 1680 rpm. With additional reduction the actual rotor speed was very slow. This was the whole purpose. A slow rigid rotor with no dissemetry of lift and no retreating blade stall until over 200mph. (Without my notes I would guess the rotor speed at about 200 mph.) That is a slow rotor. Airfoil was chosen for high lift at lower speeds. The rotor was rigid mechanically. Centrifugal force or blade strength was not required for rotor to be rigid.
I had the assembly nicely mounted on a long set of arms to do the testing. I used a calibrated bathroom scale under the heavy end to measure the lift. By my rough calculations it would lift 10 pounds per horsepower. At the time I knew helicopters flew with these ratios of pounds per horsepower.
As my 4 foot diameter rotor system hovered just below the floor joists of my basement , I was most surprised at how smooth it flew. I had built my own cyclic and collective controls and pitch had to change from lift over the top 180*to push at the lower 180*.
The rotors were as rigid as possible , centrifugal force was not required in this system. Rotors turned at a low rpm.
See my drawings on a napkin. Not very good. Remember I was trying to build a very slow speed rotor with a high forward speed. At the time I knew nothing about aerodynamics or rotors except the local library. ... which had very little.
I went on to fly the Bell 47 helicopter and did not experiment with hobby cyclogyro's any more. With the internet I see many others had the same idea since the 1930's.
What I would really like is for someone like Dave Jackson and others to study this type of slow rigid rotor with an eye on forward speed around 150 mph. I would appreciate all the arguments why it would not work and I have a few more ideas to keep this idea active. Thanks.