The bookscanners we found commercially or as DIY projects used a number of different methods to turn the pages.
One had a so called bionic finger to turn the page as one would do it with a wet finger. Another machine lowers a glas prism into the open book and sucks the ajectand pages to the prism while it is pulled up and fotos are made. One lifted the page with vacuum and slided a stick under the lifted page to turn it. Danys linearbookscanner uses vacuum to suck one page onto a curved slotted surface to guide this page under an edge while the book is moving forward.
All these concepts are interesting and work within their boundaries. But some of them cannot be build easy or cheap enough.
Our page turning concept is based on the COANDA EFFECT. Air is blown tangential over a curved surface. The stream of air will follow the curvature. A page which is moved over this area is also following the deflected stream of air.
The big advantage is that pressured air is easy to generate und other than vacuum no pages can be damaged because they are hold to the vacuum slots to strong while the rest of the book is still moving.
Next we designed the frame from aluminium profiles which can be assembled easily. Also improvements can be done without scraping to much parts.