MEET COSMO:
With 28 moving joints (20 QDD actuators + 8 servo motors), Cosmo can walk with its two feet with a speed of up to 1 m/s (0.5 m/s nominal) and balance itself even when pushed. Coordinated with the motion of its head, fingers, arms and legs, Cosmo has a loud and expressive voice for effective interaction with humans. Cosmo speaks in canned phrases from the 90’s cartoon he originates from and his speech can be fully localized in any language.
Additional Facts:
• Cosmo has a total of 28 degrees of freedom; 5 per leg, 4 per arm, 4 per hand and 2 for its neck.
• Cosmo uses a custom developed QDD actuators for its joints which can control not only the position but also the force and springiness of its joints.
• Besides sensors to measure position and torque at 20 of its joints, Cosmo uses an IMU (Inertial Measurement Unit) in its torso and custom developed linear encoder-based contact sensors in its feet to balance and walk.
• Cosmo’s main controller (brain) software is approximately 100,000 lines of C++ code.
• Cosmo can walk with two feet up to a speed of 1 meter per second (3.3 feet per second) and also change directions while walking.
• Cosmo can move its upper body (head, arms, and hands) while walking and can balance itself even when pushed.
• Cosmo’s hand has 4 individually moving fingers but can still grasp objects such as teddy bears.
• Cosmo has a loud and expressive voice coordinated with its motion for natural interactions with humans.• Cosmo is currently being upgraded with a new state of the art AI learning based walking controller.
• Using its custom developed wireless controller which uses sub-GHz frequencies, Cosmo can be controlled from a distance of 1 km (0.6 miles) away as it is resilient to interferences and obstructions.
Other interesting facts/stories:
a. Being Functional vs. Being Expressive:
COSMO’s function is to be expressive and covey emotions of the character via motion. This is very different from the other robots RoMeLa has developed where their motion needs to be efficient, exact and functional to perform a real task. Conveying emotion of a character is very challenging for robotics as we cannot quantify the look and feel of a character’s motion. Typical robots need to be “functional” but COSMO needed to be “expressive.”
b. Motion capture does not play back well on a robot:
One way to convey the emotion of a character is by using motion capture of a human actor and using that motion to play back on a robot. This technique is often used for computer games or CGI for films, however this approach does not work for physical robots. This is because the physics (physical properties such as height, weight, dimensions, etc.) is different between the human actor and the actual robot. If the motion from motion capture data of a human actor is played back on a robot, the robot becomes unstable and will fall down. Techniques to enable this has been developed at RoMeLa and new approaches are being continued to be develop.
c. Form follows function for real robots. But function follows form for COSMO:
When a real robot is designed, the mass properties and dimensions are carefully decided to obey the rules of real-world physics for it to move and function. This is especially true for robots that need to talk with two legs stably. However, for the case of COSMO, the design of the fictional robot was given which is not necessarily optimized to follow real-world physics. For example. COSMO’s head is so huge that when it walks and the head moves, it becomes unstable and can fall down. The boots of COSMO is out of proportion which makes it difficult to move its legs without colliding with its other boot. It was also a huge challenge to package all the necessary robotics components (computer, battery, sensors, actuators, etc.) into its tiny body. Designing a functional robot based on a fictional design was a monumental challenge for the team.
d. COSMO has the DNA of a soccer champion:
One of RoMeLa’s crown jewel is the humanoid robot ARTEMIS. ARTEMIS is a fully autonomous bipedal humanoid robot which is one of the most advanced in the world for its speed (fastest walking humanoid in the world when introduced) and its robustness. ARTEMIS is also a world champion soccer player. ARTEMIS became the World Champions in RoboCup 2024. RoboCup is an international autonomous robot soccer competition. RoboCup’s official goal is by the year 2050, have a team of humanoid robots play soccer against the human WorldCup champions and win. COSMO shares the technology developed for ARTEMIS – its actuator technology and its walking controller. Thus COSMO has the DNA of a soccer champion. BTW, officially, ARTEMIS stands for “Advanced Robotic Technology for Enhanced Mobility and Improved Stability.” Internally, ARTEMIS stands for “A Robot That Exceeds Messi In Soccer.” Maybe COSMO will become the new soccer champions one day.
