Russell Cameron works for DAGU Electronics, a robotics company in China. He was asked to convert a traditional Chinese dancing lion costume into a robot for display at conventions and trade shows. You can see the lion’s debut performance in the video above.
Traditional Lion Costumes
Dancing lion costumes are typically worn by two men, so they are quite large. Cameron went to a factory that makes the costumes. The lightweight paper head is made on a frame of bamboo strips. Inside, a lever is used to make the eyelids and ears move while dancers control the motions of the head and body.
Instead of people, Cameron’s creation is supported by a custom aluminum frame and driven by large DC motors.
The lion is essentially a large animatronic puppet. Cameron said the biggest challenge was reducing the weight as much as possible while maintaining durability. Cameron cut holes in the 2mm thick 6061 aluminum frame to reduce weight. The entire frame is less than 10kg with the head mounted.
The frame was largely built with just a 4″ grinder and a power drill, and is held together with pop rivets and 6mm nuts and bolts.
The lion is fully articulated with eight Degrees of Freedom (DOF). All motors are mounted in the base with 1.5mm diameter steel bicycle brake cables linking the motors to the frame. Tension springs reduce the load on the cables and motors.
Each joint has four cables, left upper, left lower, right upper, right lower. The upper or lower cables are pulled in pairs to prevent the frame from twisting. Heavy duty metal geared servos in the head operate the mouth and eyes.
Assembled Robotic Lion
Dressed and fully extended, the dancing lion is approximately 2.5m tall. Cameron programmed different poses using an Arduino-based controller, which he stitched together to form a dance sequence.
Interestingly, the lion’s debut was almost cancelled because an official was upset that there was only one. Chinese guardian lions are traditionally displayed in pairs, and he felt that a single lion would be bad luck! Fortunately, saner heads prevailed and the dancing lion had its day.
Cameron hopes that his lion will inspire other robot Makers to try out large scale projects. You can see more details about Cameron’s robot at Let’s Make Robots.