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Synopsis 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.
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Solution-driven bioinspired design: Themes of latch-mediated spring-actuated systems
Our ability to measure and image biology at small scales has been transformative for developing a new generation of insect-scale robots. Because of their presence in almost all environments known to humans, insects have inspired many small-scale flying, swimming, crawling, and jumping robots. This inspiration has affected all aspects of the robots’ design, ranging from gait specification, materials properties, and mechanism design to sensing, actuation, control, and collective behavior schemes. This article highlights how insects have inspired a new class of small and ultrafast robots and mechanisms. These new robots can circumvent motors’ force-velocity tradeoffs and achieve high-acceleration jumping, launching, and striking through latch-mediated spring-actuated (LaMSA) movement strategies. In the article, we apply a solution-driven bioinspired design framework to highlight the process for developing LaMSA-inspired robots and systems, starting with understanding the key biological themes, abstracting them to solution-neutral principles, and implementing such principles into engineered systems. Throughout the article, we emphasize the roles of modeling, fabrication, materials, and integration in developing bioinspired LaMSA systems and identify critical future enablers such as integrative design approaches.
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- Award ID(s):
- 2219644
- PAR ID:
- 10511890
- Publisher / Repository:
- MRS Bulletin
- Date Published:
- Journal Name:
- MRS Bulletin
- Volume:
- 49
- Issue:
- 2
- ISSN:
- 0883-7694
- Page Range / eLocation ID:
- 136 to 147
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1557/s43577-024-00664-2
