Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
Science. 2018 Apr 27;360(6387). doi: 10.1126/science.aao1082.
Mechanical power limitations emerge from the physical trade-off between force and velocity. Many biological systems incorporate power-enhancing mechanisms enabling extraordinary accelerations at small sizes. We establish how power enhancement emerges through the dynamic coupling of motors, springs, and latches and reveal how each displays its own force-velocity behavior. We mathematically demonstrate a tunable performance space for spring-actuated movement that is applicable to biological and synthetic systems. Incorporating nonideal spring behavior and parameterizing latch dynamics allows the identification of critical transitions in mass and trade-offs in spring scaling, both of which offer explanations for long-observed scaling patterns in biological systems. This analysis defines the cascading challenges of power enhancement, explores their emergent effects in biological and engineered systems, and charts a pathway for higher-level analysis and synthesis of power-amplified systems.
机械功率的限制源于力和速度之间的物理权衡。许多生物系统都包含增强功率的机制，使它们能够在小尺寸下实现非凡的加速度。我们通过马达、弹簧和闩锁的动态耦合来确定功率增强是如何出现的，并揭示了每个组件如何表现出自己的力-速度特性。我们从数学上证明了一种适用于生物和合成系统的弹簧驱动运动的可调性能空间。考虑到非理想的弹簧行为和参数化闩锁动力学，可以识别质量的关键转变和弹簧缩放的权衡，这两者都为生物系统中观察到的长期缩放模式提供了解释。这种分析定义了功率增强的级联挑战，探索了它们在生物和工程系统中的涌现效应，并为更高层次的功率放大系统的分析和综合开辟了道路。
