Jeff Hempel Sensei Jeff Hempel Sensei is the Director of the Traditional Japanese Swords Arts Dojo. He has studied martial arts since 1982. He has attained the rank of 5th Dan in Aikido and 4th Dan in Karate. He is the director of the youth Aikido program at Aikido of Madison and is a co-owner of East Madison Martial Arts, LLC. In addition to those ranks, Jeff Sensei also holds rank in Iai-Do and studied Jeet Kune Do (JKD) for eight years. In 2008, Sugawara Sensei named him as an official Katori Shinto-ryu teacher and granted him a Kyoshi (teacher's) License. Jeff Hempel Sensei is married and has three children and seven grandchildren.