Cook Andrés, Pandhigunta Kaanthi, Acevedo Mason A, Walker Adam, Didcock Rosalie L, Castro Jackson T, O'Neill Declan, Acharya Raghav, Bhamla M Saad, Anderson Philip S L, Ilton Mark
Department of Physics, Harvey Mudd College, Claremont, CA 91711.
School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30318.
Integr Org Biol. 2022 Jul 30;4(1):obac032. doi: 10.1093/iob/obac032. eCollection 2022.
We develop a model of latch-mediated spring actuated (LaMSA) systems relevant to comparative biomechanics and bioinspired design. The model contains five components: two motors (muscles), a spring, a latch, and a load mass. One motor loads the spring to store elastic energy and the second motor subsequently removes the latch, which releases the spring and causes movement of the load mass. We develop freely available software to accompany the model, which provides an extensible framework for simulating LaMSA systems. Output from the simulation includes information from the loading and release phases of motion, which can be used to calculate kinematic performance metrics that are important for biomechanical function. In parallel, we simulate a comparable, directly actuated system that uses the same motor and mass combinations as the LaMSA simulations. By rapidly iterating through biologically relevant input parameters to the model, simulated kinematic performance differences between LaMSA and directly actuated systems can be used to explore the evolutionary dynamics of biological LaMSA systems and uncover design principles for bioinspired LaMSA systems. As proof of principle of this concept, we compare a LaMSA simulation to a directly actuated simulation that includes either a Hill-type force-velocity trade-off or muscle activation dynamics, or both. For the biologically-relevant range of parameters explored, we find that the muscle force-velocity trade-off and muscle activation have similar effects on directly actuated performance. Including both of these dynamic muscle properties increases the accelerated mass range where a LaMSA system outperforms a directly actuated one.
我们开发了一种与比较生物力学和生物启发设计相关的闩锁介导弹簧驱动（LaMSA）系统模型。该模型包含五个组件：两个电机（肌肉）、一个弹簧、一个闩锁和一个负载质量。一个电机对弹簧加载以存储弹性能量，随后第二个电机移除闩锁，这会释放弹簧并导致负载质量移动。我们开发了与该模型配套的免费软件，它为模拟LaMSA系统提供了一个可扩展的框架。模拟输出包括运动加载和释放阶段的信息，可用于计算对生物力学功能很重要的运动学性能指标。同时，我们模拟了一个可比的直接驱动系统，该系统使用与LaMSA模拟相同的电机和质量组合。通过快速迭代模型中与生物学相关的输入参数，LaMSA系统和直接驱动系统之间模拟的运动学性能差异可用于探索生物LaMSA系统的进化动力学，并揭示生物启发LaMSA系统的设计原则。作为这一概念的原理证明，我们将LaMSA模拟与一个直接驱动模拟进行比较，后者包括希尔型力 - 速度权衡或肌肉激活动力学，或两者都包括。对于所探索的与生物学相关的参数范围，我们发现肌肉力 - 速度权衡和肌肉激活对直接驱动性能有相似的影响。同时包含这两种动态肌肉特性会增加LaMSA系统优于直接驱动系统的加速质量范围。
