Hi there,
Producing Gcode for an epitrochoid is no problem at all. A simple Excel spreadsheet can be used along with the parametric equations for the shape.
The porting on these engines is certainly not the simplest thing to get your head around, especially when timing is quoted in degrees like a 'normal' reciprocating engine. The sealing is also a problem and that is one of the things that took Felix Wankel the longest to try and figure out. His original 'sealing grid' was far more complex than the seals that you now see on a Mazda (or modern) Wankel engine.
In my opinion, a DKM engine would not be too much more difficult to build than a KKM engine. The housing would be similar (although cooling would be difficult), the rotor would be a bit more complex (since induction is through the rotor and ignition plugs are also in the rotor), however a lot of the other parts are 'simpler' to build. There is no eccentric shaft to machine and no complex bearings within the rotor. One of the big attractions for me, is that there are no internal gears used. All phasing gears are spur gears that are essentially sitting outside of all the action. The housing would need to be balanced properly if high speeds are expected (which they should be).
Overall, the DKM is a different, more complex engine than a KKM and it isn't surprising that it was simplified for production. For specialised use though, it makes so much sense. The performance is excellent and in 'special' applications (like my model aeroplanes or workbench...
) disassembling the engine to change the plugs could be tolerated.
I definitely think that more of this little engines should be made and now with CNC machines available to model engineers, it is actually within reach. I need to hurry up and get that mill going now!!!
I wonder what ever happened to all those wankel engines that were produced in the 60s and 70s. I would love to get my hands on some of those...
Regards
Warren