Bio-Inspired Theoretical Research May Improve Robots’ Effectiveness on Battlefield

These widely accepted muscle contraction models are akin to a black-box understanding of a car engine,” Culver said. “More gas, more power. It weighs this much and takes up this much space. Combustion is involved. But, you can’t design a car engine with that kind of surface-level information. You need to understand how the pistons work, and how finely injection needs to be tuned. That’s a component-level understanding of the engine. We dive into the component-level mechanics of the built-up protein system and show the design and control value of living functionality as well as a clearer understanding of design parameters that would be key to synthetically reproducing such living functionality.”

Culver stated that the capacity for Brownian motion to kick a tethered particle from a disadvantageous elastic position to an advantageous one, in terms of energy production for a molecular motor, has been illustrated by ARL at a component level, a crucial step in the design of artificial nanomotors that offer the same performance capabilities as biological ones.

This research adds a key piece of the puzzle for fast, versatile robots that can perform autonomous tactical maneuver and reconnaissance functions,” Culver said. “These models will be integral to the design of distributed actuators that are silent, low thermal signature and efficient - features that will make these robots more impactful in the field.”

Culver noted that they are silent because the muscles don’t make a lot of noise when they actuate, especially compared to motors or servos, cold because the amount of heat generation in a muscle is far less than a comparable motor, and efficient because of the advantages of the distributed chemical energy model and potential escape via Brownian motion.

According to Culver, the breadth of applications for actuators inspired by the biomolecular machines in animal muscles is still unknown, but many of the existing application spaces have clear Army applications such as bio-inspired robotics, nanomachines and energy harvesting.

Fundamental and exploratory research in this area is therefore a wise investment for our future warfighter capabilities,” Culver said.

Moving forward, there are two primary extensions of this research.

First, we need to better understand how molecules, like the tethered particle discussed in our paper, interact with each other in more complicated environments,” Culver said. “In the paper, we see how a tethered particle can usefully harness Brownian motion to benefit the contraction of the muscle overall, but the particle in this first model is in an idealized environment. In our bodies, it’s submerged in a fluid carrying many different ions and energy-bearing molecules in solution. That’s the last piece of the puzzle for the single-motor, nano-scale models of molecular motors.”

The second extension, stated Culver, is to repeat this study with a full 3-D model, paving the way to scaling up to practical designs.

Also notable is the fact that because this research is so young, ARL researchers used this project to establish relationships with other investigators in the academic community.

Leaning on their expertise will be critical in the years to come, and we’ve done a great job of reaching out to faculty members and researchers from places like the University of Washington, Duke University and Carnegie Mellon University,” Culver said.

According to Culver, taking this research project into the next steps with help from collaborative partners will lead to tremendous capabilities for future soldiers in combat, a critical requirement considering the nature of the ever-changing battlefield.