University of Twente Student Theses


Multiple framework modelling and controller design of 4 link snake robot.

Bergen, M. van (2019) Multiple framework modelling and controller design of 4 link snake robot.

[img] PDF
Abstract:This research focuses on the modelling and controller design of snake robots. Snake robots are hyper-redundant robotic systems. This property offers unique advantages in application. Their high (internal) mobility gives them unique terrain adaption possibilities. Snake robots may be applied in search and rescue missions in disaster area's or (nuclear) area's unsafe for human inspection. However, the hyper-redundancy also causes snake robots to be very complex, highly non-linear, underactuated mechanical structures that can sometimes also be non-fully observable. A snake (robot) propels it self forward by ground friction acting on its body. All these properties pose significant challenges in modelling and controller design for snake robots. In this research the kinematics and dynamics of a 4-link snake robot moving over a flat surface are modelled in 3 different frameworks. Its Newton-Euler, Euler-Lagrange and port-Hamiltonian equations of motion are derived and simulated in MATLAB and Simulink. These models and the resulting simulations are verified and turned out to be correct. Based on the derived port-Hamiltonian model of the snake robot a port-Hamiltonian shape controller is derived with the passivity based Energy-Casimir method. Numerous possible Casimirs and controller parameters are tested. The performance of the portHamiltonian shape controller is compared to the performance of an established simple joint controller (derived in the Newton-Euler framework). The performance of the port-Hamiltonian shape controller turns out to be poor. The control is unstable and has poor tracking performance. Based on the possible reasons of poor performance different recommendations for the future are given related to the port-Hamiltonian controller design.
Item Type:Internship Report (Master)
Faculty:ET: Engineering Technology
Programme:Mechanical Engineering MSc (60439)
Keywords:Modelling, Robotics, port-Hamiltonian
Link to this item:
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page