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Moisture diffusion in fibre matrix composites is one of the significant factors that affect the lives of the composite materials and lead to a decline in their working abilities and degrade their properties. Recently, many researchers have been working on the factors such as fibre volume fraction and fibre orientations that can affect the flow of moisture in composites. In the present study, different modelling techniques (FEM and bond graph) along with experimental work have been performed to validate the best fibre orientation that can delay the moisture ingress as well as reduce the resultant stresses that get developed due to moisture absorption.

The walking mobile robots have several advantages as compared to the wheel mobile robots over uneven terrains. The researchers have done a lot to develop different walking mechanisms for legged robots. Due to merits of legged robots such as scalable design, low payload-to-machine load ratio, bio-inspired locomotion, etc., the researchers have shown a great interest in the walking robots based on the Theo Jansen mechanism. In this paper, the dynamic analysis of a four-legged quadruped robot-based upon Jansen mechanism is proposed. The SimMechanics Toolbox Mathworks software is used for developing the physical modeling of the quadruped robot. Also, the real quadruped robot based on Jansen mechanism is developed and validated with a simulation model for checking the trajectory tracking performance. The proposed model of the quadruped robot is used for the application of obstacle avoidance. The fuzzy logic controller is proposed to detect and avoid the obstacles by the robots. Three Ultrasonic sensors (HC-SR04) are mounted in front of the robot to detect the obstacles. The validation of simulation and experimental results shows the performances of the navigation and obstacle avoidance fuzzy controller.

Legged robots have capability of traversing on any type of terrain with much ease and stability compared to wheeled robots. The legged robots do not have continuous contact with ground, and thus, it is easy to avoid obstacles. The objective of this paper is to model and simulate a walking mechanism for quadruple model that is stable and is able to implement different types of gaits. The stability control of legged robot is of utmost importance as compared to wheeled robot as contact from ground is discontinuous due to lifting and placing of leg. The positing of legs relative to body of robot considerably affects the stability, and also the sequence and timing in which legs are moved and placed play important role in energy efficiency. Here, model of quadruped robot with four legs has been developed using bond graph technique. Results from simulation are discussed. The comparison of different gaits is made for energy efficiency.

Generally, industrial manipulators have parallel architecture but these are not generally used because of small workspace as compared to serial manipulators. The drawbacks of serial manipulators are their low accuracy and less load carrying capacity. Therefore, hybrid manipulators are considered to be useful because they are combination of serial and parallel manipulators. In this paper, a three-dimensional hybrid manipulator with two parallel manipulators serially connected to each other is proposed. The forward and inverse dynamics of the system is modelled with the help of bond graph. Thumb and index finger of a human right hand are considered as hybrid manipulators in this paper. The objective of present work is to track the trajectory by thumb in three-dimensional space while drawing an arc on a white board with the help of a marker pen. At the end, the simulation results and conclusions are given to prove that the response follows the command with negligible error. Hence, this type of hybrid manipulator is suitable to be used in multi-fingered robotic grippers, pick and place operations, moving things etc.

The major reasons of the road accidents are the traffic problem and human erroneous driving. The researchers have started developing self-driving cars to avoid such accidents. In this paper, bicycle vehicle model along with its inverse vehicle dynamic model have been developed to track the predefined path and replace the driver. A bicycle vehicle model using bond graph (BG) is created to avoid single and two obstacles of known different geometry in predefined path. The obstacle avoidance algorithm is developed in the Matlab environment and this consists of combination of line following, tangent bug and wall following algorithm. The trajectory data from the obstacle avoidance controller is fed to the inverse controller of bicycle vehicle model to run the forward model of bicycle vehicle. For the trajectory tracking of bicycle vehicle model, the system inversion is carried out through the bond graph-based overwhelming controller. The simulation results for trajectory tracking of bicycle model is presented for single and two static obstacles with different orientations and shapes, and finally, conclusions are presented to show that response of the forward model follows the command (actual path decided by the obstacle avoidance controller) within the acceptable limits. All the results and simulations are obtained using Matlab and $${Symbols Shakti}^\circledR $$ software (Bond graph software).