The optimized musculoskeletal assembled structure of ostrich hind limb plays an important role in the efficient locomotion of ostrich. Taking the hind limb of ostrich as the biological model, via the engineering bionic technology, the biped mobile robot, the moving parts and the wearable sports equipment with superior locomotion performances can be developed.
Ostrich (Struthio camelus) is a kind of ratite, which has the flat sternum, the degenerated clavicle and without keel protrusion. The forelimbs evolved into wings, and the wings were degraded and unable to fly. However, the hind limbs (legs and feet) are thick and strong, and the continuous running speed is about 50-60 km/h, and can be maintained for about 30 minutes without feeling tired, and the sprint speed exceeds 70 km/h. The adult ostrich is 183-300 cm long, 175-275 cm tall, and weighs 60-160 kg. Therefore, the ostrich is recognized as the largest, heaviest and fastest two-legged animal on land.
The main leg muscles of ostrich are concentrated in the higher position of the hip bone near the trunk and around the thigh bone to provide powerful power. The lower parts of the leg are long and light and are only pulled by the tendon to increase the stride length and swing frequency. The intertarsal joint can also achieve passive energy-saving rebound by means of ligament pulling. Meanwhile, the permanently elevated metatarsophalangeal joint of ostrich foot can pull the tendon to store energy and rebound. The material/structural coupling assembly of the foot pad enables buffer and damp vibration. Ostrich plantar surface has a multi-curved surface and covered with the papillary group, which enhances the adhesion on ground. The toenail with an inverted triangle shape on the foot end can improve the traction property. In summary, ostrich hindlimb has the extremely optimized musculoskeletal assembled structure, which contributes significantly to the efficient locomotion of ostrich.
Bionic mobile robot, bionic walking wheel on sand, bionic boot, bionic sprinting spikes, etc.
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John. R. Hutchinson
Nina. U. Schaller