Limb work and joint work minimization reveal an energetic benefit to the elbows-back, knees-forward limb design in parasagittal quadrupeds.
Limb work and joint work minimization reveal an energetic benefit to the elbows-back, knees-forward limb design in parasagittal quadrupeds.
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四肢工作和关节工作最小化揭示了一个充满活力的好处，肘后，膝盖向前四肢设计parasostralquadrupeds。
DOI：
10.1098/rspb.2020.1517
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发表时间：
2020-12-09
期刊：
影响因子：
--
通讯作者：
Granatosky MC
中科院分区：
文献类型：
--
作者：
Usherwood JR;Granatosky MC
四足动物运动消耗大量能量。我们探索两种形式的机械工作，可能与施加这些生理需求有关。肢体功，由于力和速度之间的立场脚和质心，理论上可以是零给定的垂直肢体力和水平质心路径。为了防止俯仰，需要倾斜的垂直力分布，在站立后期前肢力大，站立早期后肢力大。相比之下，关节功——肢体关节所做的积极的机械功——将被通过髋关节或肩部关节的力所减少。测量的四足动物动力学显示出与两种工作形式的折衷减少相一致的特征，表明在某种程度上，但不是完美的，关节间的能量传递。肘部向后，膝盖向前的设计减少了低肢体工作，倾斜，垂直力剖面的关节工作需求。这种几何形状允许在远节接近垂直时支撑高强度的力，施加肘部或膝盖的低力矩，而肩膀或髋关节避免高关节力，尽管高力矩，因为近节几乎没有旋转-在此期间的平移是由于远节的旋转。
Quadrupedal animal locomotion is energetically costly. We explore two forms of mechanical work that may be relevant in imposing these physiological demands. Limb work, due to the forces and velocities between the stance foot and the centre of mass, could theoretically be zero given vertical limb forces and horizontal centre of mass path. To prevent pitching, skewed vertical force profiles would then be required, with forelimb forces high in late stance and hindlimb forces high in early stance. By contrast, joint work—the positive mechanical work performed by the limb joints—would be reduced with forces directed through the hip or shoulder joints. Measured quadruped kinetics show features consistent with compromised reduction of both forms of work, suggesting some degree of, but not perfect, inter-joint energy transfer. The elbows-back, knees-forward design reduces the joint work demand of a low limb-work, skewed, vertical force profile. This geometry allows periods of high force to be supported when the distal segment is near vertical, imposing low moments about the elbow or knee, while the shoulder or hip avoids high joint power despite high moments because the proximal segment barely rotates—translation over this period is due to rotation of the distal segment.
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DOI：
10.1242/jeb.102640
发表时间：
2014-11-01
期刊：
The Journal of experimental biology
影响因子：
--
作者：
Birn-Jeffery AV;Hubicki CM;Blum Y;Renjewski D;Hurst JW;Daley MA
通讯作者：
Daley MA
影响因子：
2
作者：
ALEXANDER, RM;JAYES, AS
通讯作者：
JAYES, AS
影响因子：
2.8
作者：
Bobbert, Maarten F.;Gomez Alvarez, Constanza B.;Weishaupt, Michael A.
通讯作者：
Weishaupt, Michael A.
DOI：
10.1115/1.1427703
发表时间：
2002-02-01
影响因子：
1.7
作者：
Kuo, AD
通讯作者：
Kuo, AD
影响因子：
2.1
作者：
Lindenfors P;Revell LJ;Nunn CL
通讯作者：
Nunn CL