A Muscle-Driven Mechanism for Locomotion of Snake-Robots

This paper presents the concept of muscle-driven locomotion for planar snake robots, which combines the advantages of both rigid and soft robotic approaches to enhance the performance of snake robot locomotion. For this purpose, two adjacent links are connected by a pair of pneumatic artificial muscles wherein an alternate actuation of these soft actuators causes a rotational motion at the connecting joints. The muscle-based actuated linkage mechanism, as a closed six-linkage mechanism, was designed and prototyped. The linear motion and force generation of the pneumatic artificial muscle was experimentally characterized using isotonic and isometric contraction experiments. A predictive model was developed based on the experimental data to describe the relationship between the force–length–pressure of the PAMs. Additionally, the muscle-driven mechanism was kinematically and dynamically characterized based on both theoretical and experimental studies. The experimental data generally agreed with our model’s results and the generated joint angle and torque were comparable to the current snake-like robots. A skx-link planar snake robot with five joints, five pairs of antagonistic muscles, and an associated pneumatic controller was prototyped and examined for simple movements on a straight-line. We demonstrated the muscle-driven locomotion of the six-link snake robot, and the results show the feasibility of using the proposed mechanism for future explorations of snake robot locomotion.

Rapid GAIT adoption for snake-like locomotion (RGASL)

Snake-like robots are low centre of gravity because they are limbless, they also have slender bodies composed of multiple actuating segments. Because of these features, snake robots are widely considered to be most adaptable among all land-based mobile robots. The multi-segmented body that provides their defining characteristic, adaptivity, also brings about the quandary of controlling many actuating segments simultaneously to create directd locomotion. Various methods for snake robot locomotion have been proposed for relatively smooth and flat surfaces. Currently there is no snake robot designed or locomotion method capable of resolving the directed mobility problem in situations where the snake robot is stuck at an impasse, or when it encounters disjointed terrains. There is no method to rapidly create new locomotion that addresses the problem or extensive time delay. This thesis makes the contribution of a modular snake robot called Striker and an elegant solution to create new snake-like robot locomotion on-the-fly, called the Explicit Gait Training (EGT) method. The EGT method allows trainer(s) to rapidly train new kinds of locomotion to address any situation at hand using their knowledge, experiences or even trial and error. The third contribution is the Standard Mobility for Snake Robots (SMMSR) is proposed as a standard platform to evaluate the evvectiveness of snake robot locomotion.

Rapid GAIT adoption for snake-like locomotion (RGASL)

Snake-like robots are low centre of gravity because they are limbless, they also have slender bodies composed of multiple actuating segments. Because of these features, snake robots are widely considered to be most adaptable among all land-based mobile robots. The multi-segmented body that provides their defining characteristic, adaptivity, also brings about the quandary of controlling many actuating segments simultaneously to create directd locomotion. Various methods for snake robot locomotion have been proposed for relatively smooth and flat surfaces. Currently there is no snake robot designed or locomotion method capable of resolving the directed mobility problem in situations where the snake robot is stuck at an impasse, or when it encounters disjointed terrains. There is no method to rapidly create new locomotion that addresses the problem or extensive time delay. This thesis makes the contribution of a modular snake robot called Striker and an elegant solution to create new snake-like robot locomotion on-the-fly, called the Explicit Gait Training (EGT) method. The EGT method allows trainer(s) to rapidly train new kinds of locomotion to address any situation at hand using their knowledge, experiences or even trial and error. The third contribution is the Standard Mobility for Snake Robots (SMMSR) is proposed as a standard platform to evaluate the evvectiveness of snake robot locomotion.