Development of Two-legged Robot

The highly dynamic legged jumping motion is a challenging research topic because of the lack of established control schemes that handle over-constrained control objectives well in the stance phase, which are coupled and affect each other, and control robot’s posture in the flight phase, in which the robot is underactuated owing to the foot leaving the ground. This paper introduces an approach of realizing the cyclic vertical jumping motion of a planar simplified legged robot that formulates the jump problem within a quadratic-programming (QP)-based framework. Unlike prior works, which have added different weights in front of control tasks to express the relative hierarchy of tasks, in our framework, the hierarchical quadratic programming (HQP) control strategy is used to guarantee the strict prioritization of the center of mass (CoM) in the stance phase while split dynamic equations are incorporated into the unified quadratic-programming framework to restrict the robot’s posture to be near a desired constant value in the flight phase. The controller is tested in two simulation environments with and without the flight phase controller, the results validate the flight phase controller, with the HQP controller having a maximum error of the CoM in the x direction and y direction of 0.47 and 0.82 cm and thus enabling the strict prioritization of the CoM.

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Manipulability and Kinematic Dependences of a Leg of the Six-Legged Robot

Proceedings of the 19th International Conference on Computer Systems and Technologies - CompSysTech'18 ◽

10.1145/3274005.3274010 ◽

2018 ◽

Cited By ~ 1

Author(s):

Ivan Chavdarov ◽

Roumen Trifonov ◽

Galya Pavlova ◽

Dilyana Budakova

Keyword(s):

Legged Robot

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Gait synthesis for a three-legged robot using Learning Automata

2011 15th International Conference on Advanced Robotics (ICAR) ◽

10.1109/icar.2011.6088586 ◽

2011 ◽

Cited By ~ 1

Author(s):

Jeeves Lopes dos Santos ◽

Cairo Lucio Nascimento

Keyword(s):

Learning Automata ◽

Legged Robot ◽

Gait Synthesis

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A Simple Analytical Tool for Legged Robot Design

Volume 4: 36th Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2012-71452 ◽

2012 ◽

Author(s):

Zhuohua Shen ◽

Justin Seipel

Keyword(s):

Analytical Solutions ◽

Inverted Pendulum ◽

Legged Locomotion ◽

Robot Design ◽

Slip Model ◽

Legged Robot ◽

Biologically Relevant ◽

Analytical Approximations ◽

Energy Conserving ◽

Spring Loaded Inverted Pendulum

Although legged locomotion is better at tackling complicated terrains compared with wheeled locomotion, legged robots are rare, in part, because of the lack of simple design tools. The dynamics governing legged locomotion are generally nonlinear and hybrid (piecewise-continuous) and so require numerical simulation for analysis and are not easily applied to robot designs. During the past decade, a few approximated analytical solutions of Spring-Loaded Inverted Pendulum (SLIP), a canonical model in legged locomotion, have been developed. However, SLIP is energy conserving and cannot predict the dynamical stability of real-world legged locomotion. To develop new analytical tools for legged robot designs, we first analytically solved SLIP in a new way. Then based on SLIP solution, we developed an analytical solution of a hip-actuated Spring-Loaded Inverted Pendulum (hip-actuated-SLIP) model, which is more biologically relevant and stable than the canonical energy conserving SLIP model. The analytical approximations offered here for SLIP and the hip actuated-SLIP solutions compare well with the numerical simulations of each. The analytical solutions presented here are simpler in form than those resulting from existing analytical approximations. The analytical solutions of SLIP and the hip actuated-SLIP can be used as tools for robot design or for generating biological hypotheses.

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