132 research outputs found
A Novel Lockable Spring-loaded Prismatic Spine to Support Agile Quadrupedal Locomotion
This paper introduces a way to systematically investigate the effect of
compliant prismatic spines in quadrupedal robot locomotion. We develop a novel
spring-loaded lockable spine module, together with a new Spinal
Compliance-Integrated Quadruped (SCIQ) platform for both empirical and
numerical research. Individual spine tests reveal beneficial spinal
characteristics like a degressive spring, and validate the efficacy of a
proposed compact locking/unlocking mechanism for the spine. Benchmark vertical
jumping and landing tests with our robot show comparable jumping performance
between the rigid and compliant spines. An observed advantage of the compliant
spine module is that it can alleviate more challenging landing conditions by
absorbing impact energy and dissipating the remainder via feet slipping through
much in cat-like stretching fashion.Comment: To appear in 2023 IEEE IRO
3D Modelling and design of a bioloid compliant quadruped leg
Dissertação de mestrado integrado em Engenharia BiomédicaIn the growing fields of rehabilitation robotics, prosthetics, and walking robots, the
modeling of a real robot is a complex and passionate challenge. On the crossing point of
mechanics, physics and computer-science, the development of a complete model involves
multiple tasks ranging from the 3D modeling of the different body parts, the measure of the
different physic properties, the understanding of the requirements for an accurate simulation, to
the development of a robotic controller.
In order to minimize large forces due to shocks, to safely interact with the user or the
environment, and knowing the ability of passive elastic elements to store and release energy,
compliant mechanisms are increasingly being applied in robots applications.
This work aims to the elaboration of an accurate efficient three-dimensional model of the
legs of the quadruped Bioloid robot and the development of a world showing the effect on
WebotsTM simulation software developed by Cyberbotics Ltd. The goal was to design a segmented
pantographic leg with compliant joints, in order to actively retract the collision and the impact of
the quadruped legs with the ground during locomotion. Geometrical and mechanical limits have
to be evaluated and considered for the modeling setup.
Finally a controller based on the use of Central Pattern Generators was improved in order
to adapt to the novel model and simple tests were performed in the WebotsTM, rendering a 3D
model simulation for the different values of spring-damping coefficients at the legs knee joint.
Through the a MATLAB® algorithm, the characterization of the joint angles during simulation was
possible to be assessed.A modelação de um robot real é um desafio complexo e fascinante na crescente área da
Robótica, que engloba desde robots de reabilitação, próteses a uma diversidade de outros
dispositivos locomotores. No cruzamento da mecânica com a física e as ciências
computacionais, o desenvolvimento de um modelo completo envolve várias tarefas que vão
desde a modelação 3D das diferentes partes do corpo, a medição das propriedades físicos
inerentes, a compreensão dos requisitos para uma simulação precisa bem como a aplicação de
um controlador robótico.
A fim de minimizar grandes forças devido a choques, interagir com segurança com o
utilizador ou o ambiente e conhecendo a capacidade de armazenagem de energia por parte de
elementos elásticos passivos, um sistema de amortecimento-mola demonstra ser uma aplicação
de crescente interesse na Robótica.
Este trabalho visa a elaboração de um modelo tridimensional eficiente e preciso das
pernas do robô quadrúpede Bioloid a ser reproduzido num mundo no software WebotsTM
desenvolvido pela Cyberbotics Ltd. O objectivo foi desenhar uma perna pantográfica segmentada
tridimensional a ser aplicada em paralelo com um sistema de amortecimento-mola de forma a
retrair activamente a colisão e o impacto das patas do quadrúpede com o solo durante a
locomoção. Deste modo para uma configuração do modelo bem sucedida são tidos em conta
limites geométricos e mecânicos.
Por ultimo, o controlador com base no uso de ‘Central Pattern Generators’ foi melhorado
a fim de se adaptar ao novo modelo e por conseguinte foram realizados testes simples usando o
simulador WebotsTM. Nesta parte experimental é realizada a simulação do modelo permitindo
avaliar o comportamento do modelo 3D para diferentes valores de coeficientes de mola e de
amortecimento aplicados a nível do joelho da perna. Através de um algoritmo MATLAB® é
possível caracterizar e analisar o comportamento doa ângulos das juntas durante a simulação
Recommended from our members
Control Implementation of Dynamic Locomotion on Compliant, Underactuated, Force-Controlled Legged Robots with Non-Anthropomorphic Design
The control of locomotion on legged robots traditionally involves a robot that takes a standard legged form, such as the anthropomorphic humanoid, the dog-like quadruped, or the bird-like biped. Additionally, these systems will often be actuated with position-controlled servos or series-elastic actuators that are connected through rigid links. This work investigates the control implementation of dynamic, force-controlled locomotion on a family of legged systems that significantly deviate from these classic paradigms by incorporating modern, state-of-the-art proprioceptive actuators on uniquely configured compliant legs that do not closely resemble those found in nature. The results of this work can be used to better inform how to implement controllers on legged systems without stiff, position-controlled actuators, and also provide insight on how intelligently designed mechanical features can potentially simplify the control of complex, nonlinear dynamical systems like legged robots. To this end, this work presents the approach to control for a family of non-anthropomorphic bipedal robotic systems which are developed both in simulation and with physical hardware. The first is the Non-Anthropomorphic Biped, Version 1 (NABi-1) that features position-controlled joints along with a compliant foot element on a minimally actuated leg, and is controlled using simple open-loop trajectories based on the Zero Moment Point. The second system is the second version of the non-anthropomorphic biped (NABi-2) which utilizes the proprioceptive Back-drivable Electromagnetic Actuator for Robotics (BEAR) modules for actuation and fully realizes feedback-based force controlled locomotion. These systems are used to highlight both the strengths and weaknesses of utilizing proprioceptive actuation in systems, and suggest the tradeoffs that are made when using force control for dynamic locomotion. These systems also present case studies for different approaches to system design when it comes to bipedal legged robots
A Design for Proprioceptive Force in 3D Agility Robot Through Use of AI
For robots to be considered effective, they should be able to maneuver through 3D environments. To achieve such mobility, robots needs to be designed in such a way that would span various topographies. So, artificial intelligence algorithms have been developed to ensure agility of the robots when walking on murky topographies. In the current state of the art legged robots, there is still much progress need to be made in research to turn them into automobiles with great agility to be used in the real world utility and provide mobility in rough. GOAT leg as a means of artificial intelligence is still a new phenomenon. There still exists a number of preliminary tests that need to be done in accessing and in the characterization of the leg’s current performance and its implications in the future. This study seeks to develop and agility model which would be useful in ensuring that the robots remain agile in such complex environments. To do this, a simulation has been through Matlab analysis. Results of the current study showed that, 3-RSR was designed to ensure that a high fidelity proprioceptive force control would enable legs with the mechanically spring stiffness. Implications and future recommendations also discussed
Design and development of a low-cost hybrid wheeled-leg for an agricultural robot : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Manawatū Campus, Palmerson North, New Zealand
The following Figures are re-used with the publishers' permission: 9a, 11c, 13b, 14a, 16a, 19. These Figures are re-used with permission from IEEE: 10a ©2005 IEEE; 10b ©2008 IEEE; 11b ©2011 IEEE; 12a ©2010 IEEE; 13a ©2015 IEEE; 13c ©2010 IEEE; 14b ©2013 IEEE; 14c ©2010 IEEE; 15 & 22 ©2016 IEEE; 16b ©2017 IEEE; 18a, b &c ©2005 IEEE; 20a & b ©2011 IEEE; 21 ©2009 IEEE; 23 ©2016 IEEE. Other Figures are either in the public domain, or re-used under a Creative Commons license.Currently, New Zealand is financially dependent on its agricultural industry quite heavily. However, the agricultural sector faces several problems such as labour shortages, environmental issues and increasing costs. In other industries, robotics and automation have been used to combat these issues successfully. Yet, in agriculture, robotics and automation have only been adopted in horticulture but not in pastoral farming (dairy, sheep, and cattle). This is because the tasks and terrain in horticultural are well defined and structured, whereas, in pastoral farming, the terrain and tasks are unstructured and dynamic. The locomotion used by current horticulture robots is either not capable of operating in unstructured terrain or are inefficient. Therefore, pastoral farming will need to adopt new forms of locomotion in automation platforms. In this thesis, it is proposed that hybrid wheel-leg locomotion will enable robots to operate in unstructured and dynamic environments. With this in mind, a low-cost prototype hybrid wheeled leg has been designed and built. The leg has been designed to specifications which were developed based on the tasks that a multipurpose horticultural and pastoral farming robot is expected to do. A joint actuator is extremely influential towards the performance of any robotic leg. Due to the unstructured terrain, in which the leg will operate, it was concluded, that a mechanically compliant actuator is required. Because of the prohibitive cost of commercially available actuators, a prototype high torque, low-cost mechanically compliant actuator was designed and built to meet the specified torque requirements. This was in addition to the design and fabrication of the leg itself. Once the leg was assembled, the sensors, actuators and the motor were interfaced with ROS™ (Robot Operating System). ROS makes it easy to coherently control each leg's DOF (Degrees of Freedom) and makes it easy to combine and control multiple legs into a robot. Testing of the leg produced very encouraging results, but there were two issues with the performance of the actuator. The first issue is due to the poor implementation of the position control algorithm that came standard with the actuator motor driver. The problem can be resolved through software or the purchase of a different motor driver. The second issue is that the actuator only outputs 23 Nm of torque, but the motor used is rated at 50 Nm. This is due to the cheap drill motor used which is from an unknown brand; it is hoped that a more powerful drill motor from a well known reputable brand will be able to output its rated torque
Sabertooth: A High Mobility Quadrupedal Robot Platform
Team Sabertooth aimed to design and realize an innovative high mobility, quadrupedal robot platform capable of delivering a payload over terrain otherwise impassable by wheeled vehicles at a speed of 5 feet per second. The robot uses a spring system in each of its legs for energy efficient locomotion. The 4ft x 3ft x 3ft freestanding four legged robot weighs approximately 300 pounds with an additional payload capacity of 30 pounds. An important feature of the robot is the passive, two degree of freedom body joint which allows flexibility in terms of robot motions for going around tight corners and ascending stairs. A distributed control and software architecture is used for world mapping, path planning and motion control
Sabertooth: A High Mobility Quadrupedal Robot Platform
Team Sabertooth aimed to design and realize an innovative high mobility, quadrupedal robot capable of delivering a payload over terrain impassable by wheeled vehicles at a speed of 5fps. The robot is designed to ascend and descend stairs. The robot uses a spring system in each of its legs for energy efficient locomotion. The 4\u27x3\u27x3\u27 freestanding four legged robot weighs approximately 300lbs with an additional payload capacity of 30lbs. The passive two degree of freedom body joint allows flexibility in terms of robot motion for going around tight corners and ascending stairs. The system integrates sensors for staircase recognition, obstacle avoidance, and distance calculation. A distributed control and software architecture is used for world mapping, path planning and motion control
- …