The praying mantis uses its front legs for locomotion, prey capture and feeding. Inspired by this dexterity, we began designing a hexapod robot that could use its front legs for both locomotion and manipulation. Our current work focuses on the middle and back legs of the robot. We designed a five degree of freedom leg, using a gimbal to form three intersecting axes of rotation at the hip to imi...

Limit cycle walkers are a class of bipeds that achieve stable locomotion without enforcing full controllability throughout the gait cycle. Although limit cycle walkers produce more natural-looking and efficient gaits than bipeds that are based on other control principles such as zero moment point walking, they cannot yet achieve the stability and versatility of human locomotion. One open questi...

We present an automated approach to robot and locomotion-controller design optimization, using reinforcement learning methods that have been successfully demonstrated to teach a real prototype quadruped various walking gaits. The same machine learning methods are used here for a different purpose: to optimize robot and locomotion-controller design. Optimization can be used before or after build...

Legged rovers are often considered as viable solutions for traversing unknown terrain. This work addresses the optimal locomotion reconfigurability of quadruped rovers, which consists of obtaining optimal locomotion modes, and transitioning between them. A 2D sagittal plane rover model is considered based on a domestic cat. Using a Genetic Algorithm, the gait, pose and control variables that mi...

Legged robots display a characteristically periodic motion. Measuring and tracking this motion has traditionally been performed using general inertial measurement techniques. While widely applied in robotics, this approach is limited in dynamic legged locomotion due to the excessive accumulation of drift from severe impact shocks (nearly 9g in single leg experiments). This paper introduces the ...

Biological systems can provide useful insights into principles of design and control of locomotion that can be applied to legged robots. In this paper we review our work on cockroaches using finite element analysis to model how loads are sensed and regulated in walking and climbing. A number of biological studies have shown that sensors that detect forces in the legs of insects are of particula...

Central Pattern Generators are used in several kinds of robot locomotion, from swimming and flying, to bipeds, quadrupeds and hexapods. It is thought that this approach can yield better results in dynamical and natural environments. In this work we expand a previous quadruped locomotion controller and propose a method to couple the step cycle phase onto the locomotor CPG of a quadruped robot, c...

Articulated Wheeled Vehicles (AWVs) are a class of wheeled locomotion systems where the chassis is connected to a set of ground-contact wheels via activelyor passively-controlled articulations, which can regulate wheel placement with respect to chassis during locomotion. The ensuing leg-wheeled systems exploit the reconfigurability and redundancy to realize significant benefits (improved stabil...

Research on biped locomotion has focused on sagittal plane walking in which the stepping path is a straight line. Because a walking path is often curved in a three dimensional environment, a 3D locomotion subsystem is required to provide general walking animation. In building a 3D locomotion subsystem, we tried to utilize pre-existing straight path (2D) systems. The movement of the center of th...

In this study, we intend to show the basis of a general legged locomotion controller with the ability to integrate both posture and rhythmic motion controls and shift continuously from one control method to the other according to the walking speed. The rhythmic motion of each leg in the sagittal plane is generated by a single leg controller which controls the swing-to-stance and stance-toswing ...