Passive Morphological Adaptation for Obstacle Avoidance in a Self-Growing Robot Produced by Additive Manufacturing

Area of Science:

• Robotics
• Materials Science
• Biomimetics

Background:

• Growing robots offer novel solutions for construction and exploration.
• Plant roots exhibit passive adaptation to environmental obstacles.
• Additive manufacturing enables complex, self-building robotic structures.

Purpose of the Study:

• To develop strategies for passive path and morphological adaptation in a growing robot.
• To investigate the robot's ability to change growth direction without explicit control.
• To leverage material properties for inherent obstacle negotiation.

Main Methods:

• Utilized a thermoplastic material for additive manufacturing of the robot's body.
• Analyzed body-environment interactions for passive obstacle avoidance.
• Tested the robot's adaptation to obstacles with varying inclinations in different environments.

Main Results:

• The robot passively adapted to obstacles up to 50° inclination, with reaction forces up to ~10 N.
• Successful penetration and adaptation observed in artificial soil and unstructured environments (30° obstacle inclination).
• Demonstrated obstacle avoidance driven by mechanical properties and body-environment interaction.

Conclusions:

• Plant-inspired passive adaptation strategies are effective for growing robots.
• Exploiting material softness allows for inherent obstacle negotiation and pathfinding.
• This approach reduces the need for complex sensing and control systems in growing robots.