Collaborative Research: Elucidating the contributions of nonlinearities in musculotendon properties to enabling locomotion in unpredictable environments.

合作研究：阐明肌肉腱特性中的非线性对在不可预测的环境中实现运动的贡献。

基本信息

批准号：
2128546
负责人：
Craig McGowan
金额：
$ 33.4万
依托单位：
University of Southern California
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2128546&HistoricalAwards=false
关键词：
Collaborative Research Elucidating contributions nonlinearities

项目摘要

For animals that locomote on uneven and diverse terrains, the ability to negotiate obstacles that can impede their forward progression and can cause instability is critical to survival. In many cases, the musculoskeletal system handles these obstacles by itself, independent of control by the nervous system, but the exact mechanisms by which this occurs are not thoroughly understood. The overall objective of this proposal is to elucidate how specific features within the musculoskeletal system achieve the appropriate locomotor behaviors without needing reflex interventions from the nervous system. To achieve this objective, the researchers will study bipedal hopping by kangaroo rats within the context of abrupt changes in slope that can disrupt forward velocity and/or cause unwanted rotational pitch of the body. Novel experiments using a specially designed rotational treadmill will make it possible to expose kangaroo rats to controlled perturbations that mimic ecologically relevant obstacles. The conceptual framework of the studies is that the components of the musculoskeletal system represent an embedded intelligence that can ease the computational burden of centralized controllers for complex dynamic systems. We advance this idea by investigating specific examples in which specialized properties link functional demands, conditional properties, and system state. Translation of the findings can solve long-standing challenges for robots moving stably over variable terrains. Furthermore, the project will involve local high school teachers, who will develop, test, implement, and assess teaching modules based upon the ongoing research to encourage pre-college students to appreciate how the study of basic biology and engineering applications are complementary. The objective of this project is to elucidate how nonlinearities within the musculoskeletal system express contextually appropriate system properties to achieve desired motor function without needing neural feedback. The approach is to study bipedal hopping by kangaroo rats with abrupt changes in slope that can disrupt forward velocity and/or cause unwanted pitch. More specifically, the research will examine how the actions of ankle extensors are coupled to the mechanics of the feet, and how this coupling is modulated by the nonlinear features of tendon. This coupling is hypothesized to provide the functional benefit of automatically making the foot compliant upon landing to mediate perturbations and then stiff at takeoff to enable propulsion. To test this hypothesis, the research team will use an integrated framework of in vivo, in situ, and in silico methods to obtain behavioral data, test mechanistic hypotheses, and manipulate component properties, respectively. A novel custom-designed rotational treadmill will make it possible to have controlled perturbations that mimic ecologically relevant obstacles. More generally, nonlinearities expressed by a system’s components can expand a system’s range of operating conditions and contexts. The findings will provide guidance for the design of nonlinearities, namely, their type and parameterization, so that the nonlinearities will be advantageous for achieving function while interacting with unpredictable environments. By collaborating with local high school teachers, the PIs will build a network of STEM teachers who will develop, test, implement, and assess teaching modules based upon the research. In addition, the project will provide interdisciplinary research training and mentoring for two graduate students and one postdoctoral fellow.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

对于在不平坦和多样化地形上移动的动物来说，克服可能阻碍其前进并可能导致不稳定的障碍的能力对于生存至关重要。在许多情况下，肌肉骨骼系统独立于神经系统的控制而自行处理这些障碍。，但这种情况发生的确切机制尚未完全了解，该提案的总体目标是阐明肌肉骨骼系统内的特定功能如何在不需要神经反射干预的情况下实现适当的运动行为。为了实现这一目标，研究人员将研究袋鼠在坡度突然变化的情况下的双足跳跃，这种变化可能会破坏前进速度和/或导致身体不必要的旋转倾斜，将使用专门设计的旋转跑步机进行新的实验。研究的概念框架是，肌肉骨骼系统的组成部分代表了一种嵌入式智能，可以减轻集中控制器的计算负担。我们通过研究特定的例子来推进这一想法，其中特殊的属性将功能需求、条件属性和系统状态联系起来，可以解决机器人在可变地形上稳定移动的长期挑战。该项目涉及当地高中教师，他们将根据正在进行的研究开发、测试、实施和评估教学模块，以鼓励大学预科学生了解基础生物学和工程应用的学习是如何互补的。阐明非线性如何肌肉骨骼系统表达了上下文适当的系统特性，以实现所需的运动功能，而不需要神经反馈。该方法是研究袋鼠大鼠的双足跳跃，其坡度的突然变化可能会破坏前进速度和/或导致不必要的俯仰。检查踝伸肌的动作如何与足部的力学耦合，以及如何通过肌腱的非线性特征来调节这种耦合，以提供在落地时自动使足部顺应的功能优势。为了测试这一假设，研究小组将使用体内、原位和计算机方法的集成框架来分别获取行为数据、测试机械假设和操纵组件属性。一种新颖的定制设计的旋转跑步机将能够模拟生态相关障碍的受控扰动。更一般地，系统组件所表达的非线性可以扩展系统的操作条件和环境范围。研究结果将为非线性的设计（即非线性的类型和参数化）提供指导，以便非线性在与不可预测的环境交互时有利于实现功能。通过与当地高中教师合作，PI 将建立一个 STEM 教师网络。他们将根据研究开发、测试、实施和评估教学模块。此外，该项目将为两名研究生和一名博士后提供跨学科研究培训和指导。该奖项反映了 NSF 的法定使命，并被认为是值得的。支持通过使用基金会的智力优点和更广泛的影响审查标准进行评估。