Extreme dynamic symmetry enables omnidirectional and multifunctional robots.

Area of Science:

• Robotics
• Mechanical Engineering
• Dynamical Systems

Background:

• Symmetry is a fundamental principle in nature, often applied to robot morphology.
• Previous applications of symmetry in robotics have primarily focused on geometric form.
• Leveraging symmetry in dynamic actuation capabilities remains an underexplored area.

Purpose of the Study:

• To introduce and formalize the concept of dynamic symmetry in robotics.
• To investigate the impact of dynamic symmetry on robot performance metrics.
• To develop and test robots specifically designed to exploit high levels of dynamic symmetry.

Main Methods:

• Introduced "dynamic symmetry" and "dynamic isotropy" as measures of uniform center-of-mass accelerations.
• Simulated over 1000 morphologies to correlate dynamic symmetry with performance.
• Developed the Argus family of spherical robots with radially oriented actuators to systematically study dynamic symmetry.

Main Results:

• Higher dynamic symmetry consistently improved trajectory tracking, task success, robustness, resiliency, and energy efficiency in simulations.
• The Argus robots demonstrated orientation-invariant locomotion, agile traversal, rapid self-stabilization, and resilience to actuator failures.
• Near-extreme dynamic isotropy in a physical robot enabled versatile locomotion and interaction capabilities.

Conclusions:

• Dynamic symmetry is a powerful design principle for enhancing robot agility, robustness, and multifunctionality.
• Designing robots with symmetry in both form and dynamics offers a general pathway to improved performance.
• This approach is crucial for developing robots capable of operating in uncertain terrestrial and extraterrestrial environments.