What is Yoshinkan Aikido?

I belong to a Yoshinkan Dojo so I will be more than happy to answer your question. Yoshinkan Aikido was founded by Gozo Shioda in 1955. Shioda was a student under the founder of the Art, Morihei Ueshiba. Shioda took Aikido and shortened the techniques to make them more practicle for police, law enforcment, and military in which Shioda taught all of who I just mentioned. Yoshinkan is big on movements and usually use "smaller circles" rather than Aikikai's "Big circles".

Yoshinkan Aikido is still taught to the Tokyo Riot Police today and other security agencies. In Japan, the women officers are required to have a black belt in Aikido, and the men have the option between Judo and Aikido. So it is very well still in use today.