They are not copies at all. ALL wheelchair manufacturers other than in some specialised cases, do not make controllers or much else.
They all use a common pool of suppliers for motors, controllers, bolts, shafts, tyres, rims, cushions, bearings, loom parts, etc etc. SOME make SOME of theit own seating parts, some are from a common bunch of suppliers, non make the tech bits like actuators etc those also come from a common pool of suppliers.
Curtis instuments is a common part supplier to anyone who wishes to buy their stuff. Like pride. They rebrand the curtis stuff and PG stuff as their own...
https://www.curtisinstruments.com/indus ... -mobility/This is no different. Most chair manufacturers make basically a frame, a few plastic parts and the rest is ordered in. Then they "build" it from all these parts. So can the chinese. They may copy each other roughly, but I dont see any particular resemblense to any other chair.
They have started making crap copies of that crap frying pan chair thought!