Dynamic balance optimization in biped robots: Physical modeling, implementation and tests using an innovative formula

doi:10.1017/S0263574714001301

Home
/
Papers
/
Dynamic balance optimization in biped robots: Physical modeling, implementation and tests using an innovative formula

Journal Article•DOI•

Dynamic balance optimization in biped robots: Physical modeling, implementation and tests using an innovative formula

Giovanni Gerardo Muscolo, Carmine Tommaso Recchiuto, Rezia Molfino

01 Dec 2015-Robotica (Cambridge University Press)-Vol. 33, Iss: 10, pp 2083-2099

TL;DR: An analytical formula for the determination of the center of mass position in humanoid platforms is proposed and tested in a real humanoid robot and outputs the real center ofmass position that minimizes the errors between real humanoid robots and virtual models.

read less

Abstract: In this paper, an analytical formula for the determination of the center of mass position in humanoid platforms is proposed and tested in a real humanoid robot. The formula uses the force-torque values obtained by the two force-torque sensors applied on the feet of the robot and the measured currents required from the motors to maintain balance as inputs. The proposed formula outputs the real center of mass position that minimizes the errors between real humanoid robots and virtual models. Data related to the Zero Moment Point positions and to the joint movements are compared with the target values, showing how the application of the proposed formula enables achieving better repeatability and predictability of the static and dynamic robot behaviour.

...read moreread less

Citations

PDF

Open Access

More filters

Journal Article•DOI•

Flexible Structure and Wheeled Feet to Simplify Biped Locomotion of Humanoid Robots

[...]

Giovanni Gerardo Muscolo, Carmine Tommaso Recchiuto

01 Mar 2017-International Journal of Humanoid Robotics

TL;DR: The unconventional use of the cylindrical helical springs in the flexible structure of the legs allows obtaining a biped robot able to achieve an alternate leg motion having only two active motors and remaining in a standing position also when the motors are not active.

...read moreread less

Abstract: The paper presents a creative design approach focused at simplifying the control of biped humanoid robots locomotion in a domestic scenario. The creative design approach is the result of intensive studies aimed at optimizing dynamic balance ZMP-based control on fully-actuated biped platforms. The innovative solution proposed in this paper is applied to the realization of a novel humanoid robot, ROLLO, which is based on the implementation of a passive flexible structure constituting the robotic legs, and of wheeled feet. The unconventional use of the cylindrical helical springs in the flexible structure of the legs allows obtaining a biped robot able to achieve an alternate leg motion having only two active motors and remaining in a standing position also when the motors are not active.

...read moreread less

18 citations

Journal Article•DOI•

T.P.T. a novel Taekwondo personal trainer robot

[...]

Giovanni Gerardo Muscolo, Carmine Tommaso Recchiuto

01 Sep 2016-Robotics and Autonomous Systems

TL;DR: The conceptual and functional design of the novel robot, T.P.T., a novel robotic prototype used in the context of Taekwondo, an Olympic martial art sport, able of interacting with children and with adult athletes is presented.

...read moreread less

11 citations

Proceedings Article•DOI•

Biomechanics of human locomotion with constraints to design flexible-wheeled biped robots

[...]

Giovanni Gerardo Muscolo¹, Darwin G. Caldwell¹, Ferdinando Cannella¹•Institutions (1)

Istituto Italiano di Tecnologia¹

03 Jul 2017

TL;DR: A biomechanical analysis of human locomotion is proposed to define a reference system for designing flexible-wheeled biped robots and to reduce the gap between humans and humanoids designing systems obtained by studying limits of human abilities instead of optimizing humanoid capabilities.

...read moreread less

Abstract: This paper proposes a biomechanical analysis of human locomotion to define a reference system for designing flexible-wheeled biped robots. The novelties proposed with this paper are twofold: 1) to revolutionize the concept to design humanoid robots as a complete imitation of humans; 2) to reduce the gap between humans and humanoids designing systems obtained by studying limits of human abilities instead of optimizing humanoid capabilities. In this first study, a human walking model is designed with some added constraints. In particular, the feet are always in contact with the ground. Results of this work are used to optimize the real flexible-wheeled biped robot, named ROLLO, with the final aim to move the robot like a human but bypassing the complexities of the human body and the robotic control.

...read moreread less

10 citations

Cites background from "Dynamic balance optimization in bip..."

...Why humanoid robots (such as the WABIAN robot composed of 41 DOFs [7, 8]) should be designed with wheels?...
[...]
...Why humanoid robots (such as the WABIAN robot composed of 41 DOFs [7, 8]) should be designed with wheels? One answer could be because the wheel can be used to bypass technological limits in complex multibody systems such as biped humanoids....
[...]

Journal Article•DOI•

Biped Robots With Compliant Joints for Walking and Running Performance Growing

[...]

Andrea Maiorino¹, Giovanni Gerardo Muscolo¹•Institutions (1)

Polytechnic University of Turin¹

31 Mar 2020-Frontiers in Mechanical Engineering

TL;DR: A 3D virtual model of a biped robot conceived with the same link dimensions (and weights) of a standard man is designed and simulated, noting how including a proper value of the compliance in the knee, power and torque of the actuators may be reduced increasing robot speed.

...read moreread less

Abstract: This paper deals with the problem of compliance in biped robots locomotion. After a first literature review, we designed and simulated a 3D virtual model of a biped robot conceived with the same link dimensions (and weights) of a standard man. In all simulation, the same input to the robot actuators is proposed, modifying only the compliance. We first validated the model and then compared results increasing and reducing compliance on hip, knee and ankle joints. The very good results underline how the robot performances may be increased including the compliant element in the knee. In particular, we noted how including a proper value of the compliance in the knee, power and torque of the actuators may be reduced increasing robot speed.

...read moreread less

9 citations

Journal Article•DOI•

Calculation of the Center of Mass Position of Each Link of Multibody Biped Robots

[...]

Giovanni Gerardo Muscolo, Darwin G. Caldwell, Ferdinando Cannella

14 Jul 2017-Applied Sciences

TL;DR: In this paper, a novel method to determine the center of mass position of each link of human-like multibody biped robots is proposed, which can be applied to different types of robots.

...read moreread less

Abstract: In this paper, a novel method to determine the center of mass position of each link of human-like multibody biped robots is proposed. A first formulation to determine the total center of mass position has been tested in other works on a biped platform with human-like dimensions. In this paper, the formulation is optimized and extended, and it is able to give as output the center of mass positions of each link of the platform. The calculation can be applied to different types of robots. The optimized formulation is validated using a simulated biped robot in MATLAB.

...read moreread less

6 citations

Cites background or methods from "Dynamic balance optimization in bip..."

...In our experiments, the robot SABIAN [2,3] had about 5 kg of errors in an unknown position and during locomotion, the controller implemented on the virtual model architecture was not able to control the real platform with this unknown error position....
[...]
...In this paper, the limits underlined in [2,3] are bypassed with the optimization of the formula based on the determination of the CoM position of each link of the robot....
[...]
...The paper is structured as follows: Section 2 presents, in synthesis, the first validated theoretical formulation proposed in [2,3]; Section 3 shows results and discussion on the second theoretical formulation to determine the center of mass position of each link of the platform....
[...]
...Another advantage of the formulation presented in this paper is that if the total CoM position of the platform is known a priori, the first formulation proposed in [2,3] can be bypassed and the CoM...
[...]
...These parameters have a lower weight with respect to other links of the platform and then a lower inertial influence [3]....
[...]

References

PDF

Open Access

More filters

Proceedings Article•DOI•

Biped walking pattern generation by using preview control of zero-moment point

[...]

Shuuji Kajita, Fumio Kanehiro, Kenji Kaneko, Kiyoshi Fujiwara, Kensuke Harada, Kazuhito Yokoi, Hirohisa Hirukawa - Show less +3 more

10 Nov 2003

TL;DR: A new method of a biped walking pattern generation by using a preview control of the zero-moment point (ZMP) is introduced and a preview controller can be used to compensate the ZMP error caused by the difference between a simple model and the precise multibody model.

...read moreread less

Abstract: We introduce a new method of a biped walking pattern generation by using a preview control of the zero-moment point (ZMP). First, the dynamics of a biped robot is modeled as a running cart on a table which gives a convenient representation to treat ZMP. After reviewing conventional methods of ZMP based pattern generation, we formalize the problem as the design of a ZMP tracking servo controller. It is shown that we can realize such controller by adopting the preview control theory that uses the future reference. It is also shown that a preview controller can be used to compensate the ZMP error caused by the difference between a simple model and the precise multibody model. The effectiveness of the proposed method is demonstrated by a simulation of walking on spiral stairs.

...read moreread less

2,090 citations

Additional excerpts

...X2i = [mu · ru + mw · (lw · sin θt + rw · cos θt )]/m2, (16) Z2i = [mu · lu + mw · (U + lw · cos θt − rw · sin θt )]/m2, (17) mw = m2 − mu, (18)...
[...]

Journal Article•DOI•

Zero-moment point — thirty five years of its life

[...]

Miomir Vukobratović, Branislav Borovac¹•Institutions (1)

University of Novi Sad Faculty of Technical Sciences¹

01 Mar 2004-International Journal of Humanoid Robotics

TL;DR: The paper gives an in-depth discussion of source results concerning ZMP, paying particular attention to some delicate issues that may lead to confusion if this method is applied in a mechanistic manner onto irregular cases of artificial gait, i.e. in the case of loss of dynamic balance of a humanoid robot.

...read moreread less

Abstract: This paper is devoted to the permanence of the concept of Zero-Moment Point, widelyknown by the acronym ZMP. Thirty-five years have elapsed since its implicit presentation (actually before being named ZMP) to the scientific community and thirty-three years since it was explicitly introduced and clearly elaborated, initially in the leading journals published in English. Its first practical demonstration took place in Japan in 1984, at Waseda University, Laboratory of Ichiro Kato, in the first dynamically balanced robot WL-10RD of the robotic family WABOT. The paper gives an in-depth discussion of source results concerning ZMP, paying particular attention to some delicate issues that may lead to confusion if this method is applied in a mechanistic manner onto irregular cases of artificial gait, i.e. in the case of loss of dynamic balance of a humanoid robot. After a short survey of the history of the origin of ZMP a very detailed elaboration of ZMP notion is given, with a special review concerning “boundary cases” when the ZMP is close to the edge of the support polygon and “fictious cases” when the ZMP should be outside the support polygon. In addition, the difference between ZMP and the center of pressure is pointed out. Finally, some unresolved or insufficiently treated phenomena that may yield a significant improvement in robot performance are considered.

...read moreread less

2,011 citations

Additional excerpts

...− (MY0i + MY1i + MY2i) / (FZ0i + FZ1i) = αi, (10) (FX0i + FX1i) / (FZ0i + FZ1i) = βi, (11) (MX0i + MX1i + MX2i) / (FZ0i + FZ1i) + [a · (FZ1i − FZ0i) / (FZ0i + FZ1i)] = γi, (12) (FY0i + FY1i) / (FZ0i + FZ1i) = δi, (13)...
[...]

Journal Article•DOI•

Optimal robot excitation and identification

[...]

Jan Swevers¹, Chris Ganseman¹, Dilek Tükel, J. De Schutter¹, H. Van Brussel¹ - Show less +1 more•Institutions (1)

Katholieke Universiteit Leuven¹

31 Oct 1997

TL;DR: Experiments on an industrial robot show that the presented trajectory design and maximum-likelihood parameter estimation approaches complement each other to make a practicable robot identification technique which yields accurate robot models.

...read moreread less

Abstract: This paper discusses experimental robot identification based on a statistical framework. It presents a new approach toward the design of optimal robot excitation trajectories, and formulates the maximum-likelihood estimation of dynamic robot model parameters. The differences between the new design approach and the existing approaches lie in the parameterization of the excitation trajectory and in the optimization criterion. The excitation trajectory for each joint is a finite Fourier series. This approach guarantees periodic excitation which is advantageous because it allows: 1) time-domain data averaging; 2) estimation of the characteristics of the measurement noise, which is valuable in the case of maximum-likelihood parameter estimation. In addition, the use of finite Fourier series allows calculation of the joint velocities and acceleration in an analytic way from the measured position response, and allows specification of the bandwidth of the excitation trajectories. The optimization criterion is the uncertainty on the estimated parameters or a lower bound for it, instead of the often used condition of the parameter estimation problem. Simulations show that this criterion yields parameter estimates with smaller uncertainty bounds than trajectories optimized according to the classical criterion. Experiments on an industrial robot show that the presented trajectory design and maximum-likelihood parameter estimation approaches complement each other to make a practicable robot identification technique which yields accurate robot models.

...read moreread less

478 citations

"Dynamic balance optimization in bip..." refers background in this paper

...FZ2i = m2 · g − FZ0i − FZ1i , (7) X2i = − (MY0i + MY1i + MY2i) / (FZ0i + FZ1i) + [(FX0i + FX1i) / (FZ0i + FZ1i)] · Z2i (8) Y2i = [(MX0i + MX1i + MX2i) / (FZ0i + FZ1i)] + [a · (FZ1i − FZ0i) / (FZ0i + FZ1i)] + [(FY0i + FY1i) / (FZ0i + FZ1i)] · Z2i , (9)...
[...]
...(8) and (9) (for i = A or i = B) can be rewritten in the following form:...
[...]

Proceedings Article•DOI•

Design of the robot-cub (iCub) head

[...]

Ricardo Beira¹, Manuel Lopes¹, M. Praca¹, José Santos-Victor¹, Alexandre Bernardino¹, Giorgio Metta², Francesco Becchi, Roque Saltaren³ - Show less +4 more•Institutions (3)

Instituto Superior Técnico¹, University of Genoa², Technical University of Madrid³

15 May 2006

TL;DR: This paper describes the design of a robot head, developed in the framework of the RobotCub project, which is the most complete humanoid robot currently being designed, in terms of kinematic complexity.

...read moreread less

Abstract: This paper describes the design of a robot head, developed in the framework of the RobotCub project. This project goals consists on the design and construction of a humanoid robotic platform, the iCub, for studying human cognition. The final platform would be approximately 90 cm tall, with 23 kg and with a total number of 53 degrees of freedom. For its size, the iCub is the most complete humanoid robot currently being designed, in terms of kinematic complexity. The eyes can also move, as opposed to similarly sized humanoid platforms. Specifications are made based on biological anatomical and behavioral data, as well as tasks constraints. Different concepts for the neck design (flexible, parallel and serial solutions) are analyzed and compared with respect to the specifications. The eye structure and the proprioceptive sensors are presented, together with some discussion of preliminary work on the face design

...read moreread less

193 citations

Journal Article•DOI•

A Fast Dynamically Equilibrated Walking Trajectory Generation Method of Humanoid Robot

[...]

Satoshi Kagami¹, Tomonobu Kitagawa², Koichi Nishiwaki², Tomomichi Sugihara², Masayuki Inaba², Hirochika Inoue² - Show less +2 more•Institutions (2)

National Institute of Advanced Industrial Science and Technology¹, University of Tokyo²

01 Jan 2002-Autonomous Robots

TL;DR: From a given input motion and the desired ZMP trajectory, the algorithm generates a dynamically equilibrated trajectory using the relationship between the robot's center of gravity and the ZMP.

...read moreread less

Abstract: This paper describes a fast dynamically equilibrated trajectory generation method for a humanoid robot. From a given input motion and the desired ZMP trajectory, the algorithm generates a dynamically equilibrated trajectory using the relationship between the robot's center of gravity and the ZMP. Three key issues are denoted: 1) an enhanced ZMP constraint which enables the calculation of robot stability even if several limbs are contacting the environment, 2) a simplified robot model is introduced that represents the relationship between its center of gravity and ZMP, 3) a convergence method is adopted to eliminate approximation errors arising from the simplified model. Combining these three key issues together with online ZMP compensation method, humanoid robot H5 have succeeded to walk, step down and so on. Experimental results using humanoid robot H5 are described.

...read moreread less

139 citations

"Dynamic balance optimization in bip..." refers background or methods in this paper

...Placing θt = 0 (then i = B) and rewriting (17) with the latter values given by lw and rw, Z2B is obtained....
[...]
...The proposed formula Placing θt = 0 (then i = A) and substituting (16) and (17) into (14) and placing θt = 0 (then i = B) and substituting (16) and (17) into (14), two different equations will be obtained....
[...]
...(14), (16) and (17) can be seen as a system composed of 6 equations in 6 unknown variables (for i = A and i = B) X2A, Z2A, X2B, Z2B, rw, lw; the relation between mw and mu is given by the Eq....
[...]
...Solving the equations system constituted by (14), (16) and (17), the positions of the center of mass are calculated in both the configurations A and B (for i = A and i = B) of the diagram of Fig....
[...]
...X2i = [mu · ru + mw · (lw · sin θt + rw · cos θt )]/m2, (16) Z2i = [mu · lu + mw · (U + lw · cos θt − rw · sin θt )]/m2, (17) mw = m2 − mu, (18)...
[...]