From about 245 to 66 million years ago, dinosaurs roamed the Earth. Although well-preserved skeletons give us a good idea of what they looked like, the way their limbs worked remains a bigger mystery. But computer simulations may soon provide a realistic glimpse into how some species moved and inform work in fields such as robotics, prosthetics and architecture.
约翰·哈钦森（John Hutchinson）是英国赫特福德郡皇家兽医学院进化生物力学教授，他的同事正在调查最早的小型恐龙的运动，这是2016年开始的长达五年Dawndinos项目的一部分。
“These dinosaurs have been hugely neglected,” Prof. Hutchinson said. “People – including me – have mostly been studying the celebrity dinosaurs likeT. rex。”
大约2.25亿年前，在三叠纪晚期，这些小的恐龙属于少数族裔，而与之同在的较大的类似鳄鱼的动物越来越多。恐龙以某种方式蓬勃发展，而那个时期的大多数其他动物都灭绝了。
Compared to their quadrupedal, heavy-built contemporaries, what stands out about these early dinosaurs is that they had an erect posture and could, at least intermittently, walk on two limbs. One theory is that their style of locomotion gave them a survival edge.
“The idea of this project is to test that idea,” Prof. Hutchinson said.
这team has started to develop computer simulations to estimate how 11 different species of extinct archosaurs – the group of animals that includes crocodiles, birds, their relatives and dinosaurs – might have moved. They will focus on five different types of motion: walking, running, turning, jumping and standing.
Simulations
To test whether their simulations are accurate, the researchers plan to give the same treatment to their living relatives – crocodiles and birds – as well. They will then compare the results to actual measurements of motion to determine how good their computer models of extinct animals are.
“It will be the first time we ground-truth (test with empirical evidence) these methods very rigorously with the best possible data we can get,” Prof. Hutchinson said.
So far, they’vemodelled the movement of aMussaurus– an early cousin of giant plant-eating sauropod dinosaurs such asBrontosaurus。这Mussauruswas much smaller and researchers wanted to see whether it moved on four legs like its larger relatives. The first reconstructions of the animal had it on four legs because it had quite big arms, said Prof. Hutchinson.
使用阿根廷保存完好的化石扫描，他们能够生成其运动的新模型。Hutchinson教授和他的团队发现实际上是Bipedal。由于其前肢的棕榈向内朝内，并且前臂接头无法向下旋转，因此它不可能在四腿上行走。因此，它无法将其前腿种在地面上。
“It wasn’t until we put the bones together in a 3-D environment and tried playing with their movements that it became clear to us that this wasn’t an animal with very mobile arms and hands,” Prof. Hutchinson said.
Robotics
项目期间产生的仿真可能对动物学家有用。但是，根据Hutchinson教授的说法，例如，它们的应用程序也可能不太明显，可以帮助改善机器人的移动方式。
Accurate models are needed to replicate the motion of animals, which robotics researchers often take inspiration from. Mimicking a crocodile, for example, could be of interest to create a robot that can both swim and walk on land.
Prof. Hutchinson also regularly gets contacted by film and documentary makers who are interested in using his simulations to create realistic animations. “It’s hard to make bigger, or unusual, animals move correctly if the physics isn’t right,” Prof. Hutchinson said.
Understanding the locomotion of the very largest dinosaurs is the aim of a project being undertaken by paleobiology researcher Alexandra Houssaye and her colleagues from France’s National Centre for Scientific Research and the National Museum of Natural History in Paris. Through theirGravibone project,which began last year, they want to pin down the limb bone adaptations that allow large animals to carry a heavy skeleton.
Houssaye博士说：“我们真的想了解什么（骨骼特征）与大规模有关。”
Massive
到目前为止，研究表明，较大动物的四肢长骨比较小动物的骨头更健壮。但是，这种普遍趋势仅在表面上观察到。外部和内部骨结构随着时间的流逝而进行了调整，以帮助支持动物的体重。例如，尽管较小的陆地动物具有空心的肢体骨头，但大象，犀牛和河马等大型动物的中间有结缔组织。
Among the largest animals and their ancestors there are also other differences. The limb bones of modern rhinos, for example, are short and heavy. But their prehistoric relatives calledIndricotherium, the largest land mammal that ever lived, had a less stocky skeleton. “It’s interesting to see that the biggest didn’t have the most massive (frame),” Dr. Houssaye said.
这team is studying both living and extinct animals, focussing on elephants, rhinos, hippos, prehistoric mammals and dinosaurs such as sauropods – a group that includes the biggest terrestrial animals of all time.
到目前为止，他们已经比较了犀牛祖先的马，tap，犀牛和化石的脚踝骨骼。他们发现，对于相同质量的动物，有差异取决于它们是短而粗壮还是四肢较长。在较少的牲畜动物中，两个脚踝骨骼往往更加截然不同，而它们在大规模建造的动物中更加紧密，可能是为了加强发音。
“It’s not only the mass (of the animal) but how the mass is distributed on the body,” said Dr. Houssaye. “For us that was interesting.”
3D modelling
这ir next step will be to scan different limb bones and analyse their inner structure. They will also use 3D modelling to figure out how much weight different parts of the bones can handle in different spots, for example.
这results from the project could help make more efficient prosthetics for people and animals, Dr. Houssaye said. Designers will be able to better understand how different features of limb bones, such as thickness and orientation, relate to their strength, enabling them to create materials that are lighter but more resistant.
Similarly, Dr. Houssaye has also had interest from the construction industry which is looking for new types of materials and more effective building techniques. Pillars supporting heavy buildings, for example, could be made using less material by improving their inner structure instead.
Houssaye博士说：“骨骼如何适应（重量）对建筑有影响。”‘（建筑师）试图创建能够支持重量重量的结构。”
Filed Under:Rapid prototyping,Robotics • robotic grippers • end effectors
