Cosserat Rod-Based Dynamic Modeling of a Hybrid-Actuated Soft Robot for Robot-Assisted Cardiac Ablation

Abstract

Soft robotics has emerged as a promising field due to the unique characteristics offered by compliant and flexible structures. Overcoming the challenge of precise position control is crucial in the development of such systems that require accurate modeling of soft robots. In response, a hybrid-actuated soft robot employing both air pressure and tendons was proposed, modeled, and validated using the dynamic Cosserat rod theory. This approach comprehensively addresses various aspects of deformation, including bending, torsion, shear, and extension. The designed robot was intended for robot-assisted cardiac ablation, a minimally invasive procedure that is used to treat cardiac arrhythmias. Within the framework of the Cosserat model, dynamic equations were discretized over time, and ordinary differential equations (ODEs) were solved at each time step. These equations of motion facilitated the prediction of the robot’s response to different control inputs, such as the air pressure and tension applied to the tendons. Experimental studies were conducted on a physical prototype to examine the accuracy of the model. The experiments covered a tension range of 0 to 3 N for each tendon and an air pressure range of 0 to 40 kPa for the central chamber. The results confirmed the accuracy of the model, demonstrating that the dynamic equations successfully predicted the robot’s motion in response to diverse control inputs.

Toward precise force control of soft hand grasping: The viscoelastic parameter estimation of pseudo-soft-rigid-model by applying logarithmic decrement method

“…Piecewise Constant Curvature (PCC) modeling [25][26][27], Cosserot rod theory modeling [18,[28][29][30], disc-thread modeling [31,32], and 3D Finite Element Models [33][34][35] have been vastly explored. However, using Cosserot rod theory and disc-thread modeling presents an overall increased computational difficulty.…”

Design Optimization of a Hybrid-Driven Soft Surgical Robot with Biomimetic Constraints

“…Similarly, Shahid et al [ 38 ] developed a soft composite finger with an adjustable joint stiffness using a hybrid actuation approach combining cable tension and air pressure. Furthermore, Roshanfar et al [ 39 , 40 , 41 , 42 ] developed a continuum model of a tendon–air hybrid actuated soft robot based on the Cosserat rod model that was specifically designed for applications in the RAMIS.…”