Robotic Biomimicry | Ton Van Den Bogert | TEDxClevelandStateUniversity
Ron Corte, who is partially paralyzed from a 2005 spinal cord injury, argues that understanding natural mechanisms, particularly those of horses, is key to advancing robotics for mobility assistance. He demonstrates how biological systems achieve efficiency by using coupled joint motions, which informs the design of advanced, energy-regenerating prosthetic limbs. The presentation concludes by suggesting that by applying these deep biological principles, robotics can eventually surpass natural capabilities. ## Speakers & Context - **Speaker:** Unnamed speaker; currently a professor in mechanical engineering, but started scientific career in a veterinary school, studying anatomy and movement of horses. - **Colleagues:** Dan Simon and Hanz Richter. ## Theses & Positions - Both mobility challenges faced by soldiers in Afghanistan and individuals with disabilities can be addressed by robotics. - The design of optimal assistive technology should draw critical lessons from nature, particularly the highly efficient joint mechanics found in horses. - While current robots are very far behind animals, understanding natural principles allows for the development of superior, energy-efficient assistive devices that can even improve upon nature. - The ultimate goal of robotic design is to build a leg that performs every function of a human leg while using minimal energy, all controlled by software. ## Concepts & Definitions - **Coupled joint motions:** The principle where flexing one joint simultaneously causes flexing in other joints, as observed in horses. - **Mechanical coupling:** The physical connection between motors, illustrated by an electric cable connecting two motors, causing them to move identically. - **Electrical coupling:** Energy transfer through an electrical circuit, demonstrated by connecting two motors via a cable to make them move in sync. ## Mechanisms & Processes - **Problem identification (Soldiers/Disabled):** Difficulty moving people and equipment across challenging terrain (e.g., mountains, narrow trails) due to physical limitations or logistical constraints. - **Mechanical Model Creation:** Dissecting a horse leg and moving the joints to create a mechanical model illustrating coupled motion between the hip, knee, and ankle. - **Principle of Movement (Horses):** Long tendons cross multiple joints and are perfectly arranged to coordinate movements, meaning the hoof is always perfectly positioned upon ground contact. - **Energy Efficiency:** Most work in horse locomotion is done by tendons; the muscles do minimal work, leading to excellent fuel economy (100 miles per gallon equivalent). - **Design Innovation (Prosthetics):** Applying mechanical engineering to simulate biological attachment points by proposing external elastic cables attached to pulleys (conceptually allowing walking to become 50% easier). - **Energy Management in Prosthetics:** The ability to direct energy flow between two motors, disconnect motions, and store excess energy in batteries and capacitors. ## Timeline & Sequence - **2001:** Department of Defense began spending hundreds of millions of dollars on robotic technology for walking. - **Period:** Horse anatomy study conducted while the speaker was a graduate student; mechanical model was built. - **Last 10 years:** Speaker prepared a lecture on muscle mechanics, recalling horse leg design. - **Today:** Presentation of the current prototype prosthetic leg. ## Named Entities - **Cleveland** — location where Parker-Hannifin is situated. - **Afghanistan** — operational area where military movement difficulties were noted. ## Numbers & Data - Year of DoD investment start: **2001**. - Robot capacity: **150 pounds**. - Robot top speed: **four miles per hour**. - Robot fuel efficiency: **four miles out of one gallon of gasoline**. - Comparison (Humvee): **10 times faster** and **10 times more weight** capacity than the Big Dog. - Big Dog fuel requirement for 100-mile trip: **25 gallons of gasoline**. - Horse fuel economy (equivalent): **100 miles per gallon** or better. - Comparative speed: Horse can travel **six times faster** than the best robot. - Energy storage potential: Ability to store extra energy for later use in **batteries and capacitors**. ## Examples & Cases - **Ron Corte's injury:** Spinal cord injury in **2005**, resulting in partial paralysis in the left foot. - **Military Problem:** In **Afghanistan**, soldiers had to leave vehicles behind because mountain trails were too narrow and rocky; the Battle of Tora Bora was partly unsuccessful due to equipment limitations. - **Robotic Example 1 (Big Dog):** A robot capable of carrying **150 pounds** for soldiers. - **Robotic Example 2 (Exoskeleton):** The **Indego exoskeleton**, developed by **Parker-Hannifin** in Cleveland, for people with disabilities. - **Robotic Example 3 (Sarcos):** An exoskeleton powered by a **giant hydraulic pump** requiring a long hose, unsuitable for mountains. - **Biological Example (Horses):** The efficiency of the horse leg, which utilizes tendons to achieve superior speed, load capacity, and fuel economy using only plant matter. - **System Concept:** A prototype prosthetic leg featuring two motors (knee and ankle) controlled by switches and software, designed for above-knee amputees. ## Tools, Tech & Products - **"Big Dog" robot:** A robotic device for soldier assistance. - **Robotic exoskeletons:** General category of strength/endurance aids. - **Indego exoskeleton:** Specific exoskeleton developed by **Parker-Hannifin**. - **Sarcos exoskeleton:** A hydraulic exoskeleton requiring hoses. - **Elastic cable:** Used conceptually to improve walking assist by running from the waist to the heel. - **Lego motors:** Used in a simple demonstration of electrical coupling. - **Prototype prosthetic leg:** System featuring two motors (knee and ankle) for above-knee amputees, controlled by computer switches. - **Computer model/Simulation:** Used by the speaker to test attachment points for external tendons. ## References Cited - None explicitly cited, though the speaker's background in veterinary anatomy is used as a foundational source of knowledge. ## Trade-offs & Alternatives - **Electric Motors vs. Hydraulics:** Electric motors offer a pathway to more advanced, controllable, and potentially regenerative systems compared to the high-dependency/logistical complexity of hydraulic pumps. - **Robotics vs. Horses (Practical):** Horses are superior in maneuverability and energy source (foraging) over current robotic models for rugged terrain. - **Current Robotics vs. Future Robotics:** Current robots are energy-intensive and physically limited (e.g., gas requirements); future designs aim for near-biological energy efficiency. ## Counterarguments & Caveats - Current robotic designs, like the "Big Dog," are highly impractical for long-distance, off-grid deployment due to gas constraints (e.g., a 100-mile trip requiring 25 gallons). - Robots, even advanced ones, still lack the innate ability of animals to self-regulate and optimize movement efficiency. ## Methodology - **Comparative Analysis:** Comparing operational limitations of current military/civilian robots (Big Dog, Sarcos) against the performance metrics of horses. - **Anatomical Study:** Dissecting and modeling the joints of a horse leg to isolate the biomechanical advantages of its tendon structure. - **Engineering Simulation:** Utilizing computer models to simulate attaching external tendons at various points on a human leg to calculate potential mechanical assistance for walking. - **Electrical Demonstration:** Showing electrical coupling between motors to model the concept of coordinated movement without direct mechanical linkage. ## Conclusions & Recommendations - The immediate suggestion is to adopt principles derived from horses' biomechanics to guide robotic design. - Future robotics must achieve energy regeneration and precise, adaptable motor control via software. - The goal is to build a machine that emulates—and surpasses—the efficiency of biological movement. ## Implications & Consequences - If the principles learned from horses are applied, future prosthetics could achieve near-natural movement efficiency while offering software-controlled adaptability that animals cannot match. - The research pushes the boundaries from mere *replacement* technology (a motor substitute) to *enhancement* technology (surpassing nature's design). ## Verbatim Moments - *"Both of these problems can be solved by robotics."* - *"The Battle of Tora Bora was unsuccessful partly because we couldn't move enough people and equipment into those mountains."* - *"If this 'Big Dog' robot has to go on a 100-mile trip, it has to carry 25 gallons of gasoline. That's just about all it can carry, so that's obviously not very practical yet."* - *"And it turns out their fuel economy is about 100 miles per gallon or even better."* - *"And that's really the secret why horses get 100 miles per gallon and why they never stumble, even when they're tired."* - *"If I flex this knee joint, all the other joints are flexing at the same time."* - *"This is a beautiful mechanism that horses have developed over millions of years."* - *"And I asked the question to myself: what if you could attach tendons anywhere you wanted on a human leg, could you make walking easier?"* - *"This could do about half of the work that's required for walking."* - *"There's only an electrical coupling. This is precisely what happened in the leg of the horse when I moved the knee and the other joints started moving."* - *"The possibilities are really only limited by our imagination, and it can all be controlled by software."*