As a robot could be stable statically standing on three or more legs, a six legged walking robot can be highly flexible in movements and perform different missions without dealing with serious kinematic and dynamic problems. An experimental six legged walking robot with 18 degrees of freedom is studied and built in this paper. The kinematic and gait analysis formulations are demonstrated by an e...

In this paper, a new method was proposed for the navigation of a mobile robot in an unknown dynamic environment. The robot could detect only a limited radius of its surrounding with its sensors and it went on the shortest null space (SNS) toward the goal. In the case of no obstacle, SNS was a direct path from the robot to goal; however, in the presence of obstacles, SNS was a space around the r...

In the previous work we presented a new gait for humanoid robots, such as the Nao developed by Aldebaran. This new gait implemented on a Nao, reduces the energy consumption by 41%. Then main feature of the new gait is the absence of an area of support. The foot can rotate freely around the ankle joint. This feature makes the gait suited for uneven terrains. Stability is an important aspect of w...

Aiming at the functional requirement of climbing up the stairs, the dynamics and stability during a tracked mobile robot’s climbing of stairs is studied. First, from the analysis of its cross‐country performance, the mechanical structure of the tracked mobile robot is designed and the hardware composition of its control system is given. Second, based on the anal...

This paper presents the design and implementation of a singularity-free tracking algorithm for robot manipulators using a hybrid system approach. A hybrid robot motion controller is designed to ensure feasible robot motion in the neighborhood of kinematic singularities. The hybrid control system has a two-layered hierarchical structure, a discrete layer and a continuous layer. The robot workspa...

Design of autonomous underwater robots is particularly difficult due to the physical and sensor challenges of the underwater environment. Inaccessibility during operation and low probability of failure recovery makes robot stability and reliability paramount. Building an accurate and complete virtual world simulation is proposed as a necessary prerequisite for design of an autonomous underwater...

in this paper, a robust integral of the sign error (rise) feedback controller is designed for a rigid-link electrically driven (rled) robot manipulator actuated by direct current dc motor in presence of parametric uncertainties and additive disturbances. rise feedback with implicitly learning capability is a continuous control method based on the lyapunov stability analysis to compensate an add...

The postural stability of bipedal robots is investigated in perspective of foot-rotation during locomotion. With foot already rotated, the biped is modeled as an underactuated kinematic structure. The stability of such biped robots is analyzed by introducing the concept of rotational stability. The rotational stability investigates whether a biped would lead to a flat-foot posture or the biped ...

In this paper, the configuration of a five-limbed modular robot is introduced. A specialised locomotion gait is designed to allow for omni-directional mobility. Due to the large diversity resulting from various gait sequences, a criteria for selecting the best gaits based on their stability characteristics is proposed. A series of simulations is then performed to evaluate the various gaits in d...

In this work a motion control scheme, which belongs to the class of the control schemes known as a sliding mode control with disturbance estimation is proposed. Adaptive fuzzy disturbance estimator works as an identifier of variable part of a system dynamics. Adaptation algorithm is derived by using the Lyapunov stability theory and provides global asymptotic stability of the state errors. For ...