Before revision:  With BRICKxAR, real LEGO brick construction is guided by virtual bricks in the right place at the right time, step by step. Virtual and real object occlusions are implemented to enable a natural appearance of virtual bricksinside real bricks . LEGO players' hand detection and occlusion are realized to allow a realistic immersive AR experience, in which virtual bricks can be "grasped" by the real hand, facilitating hand-eye coordination in AR.
After revision:  With BRICKxAR, real LEGO brick construction is guided by virtual bricks . Compared with the state-of-the-art, accuracy of the virtual - physical model alignment is significantly improved through a new design of marker-based registration, which can achieve an average error less than 1mm throughout the model. Realistic object occlusion is accomplished to reveal the true spatial relationship between physical and virtual bricks . LEGO players' hand detection and occlusion are realized to allow a realistic immersive AR experience, in which virtual bricks can be "grasped" by the real hand, facilitating hand-eye coordination in AR.