A Novel Pneudraulic Actuation Method to Enhance Soft Robot Control

Area of Science:

• Robotics and Mechanical Engineering
• Fluid Dynamics
• Control Systems

Background:

• Soft fluidic actuators (SFAs) are crucial for medical robotics, offering safer human-robot interaction than rigid devices.
• Traditional pneumatic and hydraulic actuation methods for SFAs have limitations in speed, precision, and complexity.
• There is a need for advanced actuation systems to enhance SFA performance in industrial and medical applications.

Purpose of the Study:

• To introduce and evaluate a novel pneudraulic actuation system for SFAs, combining pneumatic and hydraulic circuits in series.
• To compare the performance of the proposed pneudraulic system against conventional actuation methods.
• To develop and implement a model-based control strategy for optimizing SFA dynamic behavior.

Main Methods:

• A comparative assessment of bending performance and audible noise levels for different fluidic actuation techniques.
• Analysis of fluid-structure interactions and the impact of trapped air in SFAs.
• Investigation of fluidic circuit parameters (tubing dimensions, fluid medium) on system dynamics.
• Development of a model-based PID controller using hydraulic-electric analogy and circuit theory.

Main Results:

• The proposed pneudraulic system demonstrated significant improvements in actuation speed and reduced audible noise.
• The PID controller enhanced actuation speed by 52.63% and reduced noise by 17.17%.
• Fluid mechanics and circuit design parameters were shown to critically impact SFA dynamic behavior.

Conclusions:

• The novel series pneudraulic actuation system offers a promising solution for enhancing SFA performance.
• Model-based control focusing on fluid dynamics can effectively optimize SFA speed and noise levels.
• This research highlights the importance of fluid mechanics in designing advanced soft actuators for demanding applications.