A5103164657- Robotic Locomotion and Control
- Robot Manipulation and Learning
- Robotic Mechanisms and Dynamics
- Dynamics and Control of Mechanical Systems
- Control and Dynamics of Mobile Robots
- Muscle activation and electromyography studies
- Prosthetics and Rehabilitation Robotics
- Adaptive Control of Nonlinear Systems
- Advanced Control Systems Optimization
- Motor Control and Adaptation
- Teleoperation and Haptic Systems
- Adhesion, Friction, and Surface Interactions
- Gaussian Processes and Bayesian Inference
- Injury Epidemiology and Prevention
- Mechanical stress and fatigue analysis
- Cerebral Palsy and Movement Disorders
- Biomimetic flight and propulsion mechanisms
- Tactile and Sensory Interactions
- Extremum Seeking Control Systems
- Vehicle Dynamics and Control Systems
- Balance, Gait, and Falls Prevention
- Soil Mechanics and Vehicle Dynamics
- Robotic Path Planning Algorithms
- Advanced Control Systems Design
University of Birmingham
2014-2022
Australian National University
2010-2014
The success of robots in real-world environments is largely dependent on their ability to interact with both humans and said environment. FP7 EU project CoDyCo focused the latter these two challenges by exploiting rigid compliant contacts dynamics robot control problem. Regarding former, properly manage interaction side, an estimation human behaviors intentions necessary. In this letter, we present building blocks such a human-in-the-loop controller, validate them simulation iCub humanoid...
This paper presents a new nonlinear model of the normal force that arises during compliant contact between two spheres, or sphere and flat plate. It differs from well-known existing by only single term. The advantage is it accurately predicts measured values coefficient restitution spheres plates various materials, whereas other models do not.
A proportional-integral-derivative (PID) controller is a control loop feedback mechanism widely employed in industrial systems. The parameters tuning sticking point, having great effect on the performance of PID system. There no perfect rule for designing controllers, and finding an initial good guess well-performing difficult. In this paper, we develop knowledge-based particle swarm optimization by incorporating dynamic response information into optimizer. Prior knowledge not only empowers...
Planning robust robot manipulation requires good forward models that enable plans to be found. This work shows how achieve this using a model learned from data plan push manipulations. We explore learning methods (Gaussian Process Regression, and an Ensemble of Mixture Density Networks) give estimates the uncertainty in their predictions. These are utilised by predictive path integral (MPPI) controller box goal location. The planner avoids regions high model. includes both inherent dynamics,...
Dynamic manipulability of robots is a well-known tool to analyze, measure and predict robot's performance in executing different tasks. This provides graphical representation set metrics as outcomes mapping from joint torques the acceleration space any point interest robot such end-effector or center mass. In this paper, we show that weighting matrix, which included aforementioned mapping, plays crucial role results dynamic analysis. Therefore, finding proper values for matrix key achieve...
Robots are increasingly being required to perform tasks which involve contacts with the environment. This paper addresses problem of estimating environmental constraints on robot's motion. We present a method estimates such constraints, by computing null space set velocity vectors differ from commanded velocities during contacts. further extend this handle unilateral for example when robot touches rigid surface. Unlike previous work, our is based kinematics analysis, using only...
In this paper, a new control algorithm is presented for implementing hopping and balancing motions on planar machine with single actuated revolute joint. Starting simple balancing, it extended to perform trajectory-tracking maneuvers, which enables the crouching, lift-off flight phases of hop, as well re-balancing after landing. Simulation results are showing that system works well, not significantly affected by small amounts slipping between foot ground.
This paper introduces dynamic manipulability of the center mass (CoM) as a metric to measure robots' physical abilities accelerate their CoMs in different directions. By decomposing effects velocity dependent constraints, such unilateral contacts and friction cones, CoM is defined independent which depends only on robot's configuration inertial parameters. Thus, this any choice controller expresses robots. important property makes proposed proper tool study, analyse design current future The...
This paper proposes a momentum-based balancing controller for robots which have non-rigid contacts with their environments. regulates both linear momentum and angular about the center of mass robot by controlling contact forces. Compliant models are used to determine forces at points. Simulation results show performance on four-link planar standing various compliant surfaces while unknown external in different directions acting robot.
This paper proposes a method to realize desired contact normal forces between humanoids and their compliant environment. By using models, are converted deformations of surfaces. To achieve forces, controlled by controlling the point positions. Parameters models assumed be known or estimated approach described in this paper. The proposed methods for estimating parameters force implemented on LWR KUKA IV arm. verify both methods, experiments performed with arm while its end-effector is two...
During the initial trials of a manipulation task, humans tend to keep their arms stiff in order reduce effects any unforeseen disturbances. After few repetitions, perform task accurately with much lower stiffness. Research human motor control indicates that this behavior is supported by learning and continuously revising internal models task. These predict future states anticipate necessary actions, adapt impedance quickly match requirements. Drawing inspiration from these findings, we...
This paper presents an angular momentum based controller to control the balancing motion of a spatial underactuated robot with three degrees under-actuation. The algorithm is on idea decoupling robot's instantaneously into bending and swivelling motions. property obtained by using constant velocity joint as 2-DoF active robot. Simulation results show performance during some interesting motions such straightening, crouching reorienting last two motions, which are motion, demonstrated here for...
This paper studies the effects of hand contact force on stability a planar humanoid robot while translational perturbations are applied to its foot. A momentum based controller is used control robot's motion during perturbations. Simulation results show that displacements center pressure (CoP) foot decrease substantially when there supportive between and environment. The simulation CoP handle forces also conform with experiments human subjects different positions contact. conformity shows...
Humans are capable of adjusting their posture stably when interacting with a compliant surface. Their whole-body motion can be modulated in order to respond the environment and reach stable state. In perceiving an uncertain external force, humans repetitively push it learn how produce Research human motor control has led hypothesis that central nervous system integrates internal model sensory feedback generate accurate movements. However, brain understands force through exploration...
Stairways, public transport and inclined walkways are often considered as sites with higher likelihood of falls due to a sudden loss balance. Such usually marked warning signs, equipped non-slip surfaces handles or handrails avert decrease this likelihood. Especially, supposed provide additional support in cases However, the mechanisms using for balance at different heights not yet fully disclosed. We simulated full body perturbations by applying an anterior force waist investigated...
A polyhedral friction cone is a set of reaction wrenches that an object can experience whilst in contact with its environment. This polyhedron powerful tool to control object's motion and interaction the It be derived analytically, upon knowledge environment geometries, point locations coefficients. We propose estimate so priori these quantities no longer required. Additionally, we introduce solution transform estimated avoid re-estimation while moves. present analysis demonstrate...
A polyhedral friction cone is a set of reaction wrenches that an object can experience whilst in contact with its environment. This polyhedron powerful tool to control object's motion and interaction the It be derived analytically, upon knowledge environment geometries, point locations coefficients. We propose estimate so priori these quantities no longer required. Additionally, we introduce solution transform estimated avoid re-estimation while moves. present analysis demonstrate...