Between two founders
Shōdōkan Aikidō is the competitive stream of aikidō created by Tomiki Kenji (富木謙治, 1900–1979), born in Kakunodate in Akita prefecture, and shaped by an education under the two most consequential budō figures of modern Japan: he was a high-graded jūdōka under Kanō Jigorō and one of the earliest senior students of aikidō's founder Ueshiba Morihei. Tomiki became a professor at Waseda University, and it was as an educator that he asked the question that defines his school: if aikidō's principles are real, they should be testable against a resisting opponent, as Kanō had made jūdō testable.
Randori and the knife
From the 1950s Tomiki developed a randori system at Waseda in which aikidō techniques are trained competitively, its signature format matching an unarmed player against one holding a training replica of a tantō, with points scored for valid strikes and for successful takings of the knife. Tomiki himself preferred names like "new aikidō" and "aikidō competition"; the label Tomiki Aikidō was applied by others to mark the school off from the non-competitive mainstream, which regarded scored contest as contrary to the founder's intent. The disagreement was real and remains the school's defining controversy.
Kanō's question asked of Ueshiba's art: if a principle is real, it must survive an opponent who resists.
The Shōdōkan and the school today
The name Shōdōkan comes from the headquarters dōjō established in Ōsaka in 1976, in the last years of Tomiki's life. Organisationally the school is carried by the Japan Aikido Association, which Tomiki founded, alongside international federations that hold regular championships. Within the wider aikidō world it remains the empirical wing: the one school whose answer to the question "does it work?" is to hold the match and find out.