Concrete & helicopter thingy

[Mutiara]

Has anyone had concrete laid recently? My french neighbour had a concrete floor laid recently and although I didn't see it being done, I think they used one of those "helicopter" thingys to get a lovely smooth surface. Does anyone know how to use one of these or how best to get a smooth finish without any ripples? Hubby wants to lay a small area in our barn and wants it to look like Arnaud, our neighbours new floor. (personally I think he just wants a new toy to play with! ).

M.