Reuleaux was the appointed chairman of the German panel of judges for the Sixth World Industrial Fair opened in Philadelphia on 10 May 1876.

He admitted that German-made goods were far inferior to those of other countries and that German industry's guiding principle was “billig und schlecht” (English: cheap and shoddy).

Reuleaux was a consultant to the development of the Otto-Langen internal combustion engine, winner of the 1867 World's Fair in Paris, France, based on efficiency.

[2] Reuleaux served on several international juries and commissions and considerably involved in formation of a patent system, as he was active in German politics.

At the expense of the German government, he directed the design and manufacture of over 300 beautiful models of simple mechanisms, such as the four-bar linkage and the crank.