Embarrassment struck at a Moscow tech event when AIDOL, Russia’s first humanoid AI robot, lost its balance and fell face down during its debut walkout. Developers said the mishap was a “learning experience” as the robot attempted to wave to the crowd before toppling over.

At a technology event in Moscow on November 11, Russian robotics start-up AIDOL's humanoid robot, which is also named AIDOL, made a high-profile appearance that ended abruptly when it stumbled and fel...