• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1764-1766
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• 2007

This paper aims to generate the static walking pattern of a biped robot on stairs and to show the effectiveness of the proposed algorithm using its ankle and pelvis. Differently from the previous biped robots, our biped robot has the peculiar mechanism on its ankle and pelvis. By using this mechanism, we can reduce the load in the knee when a biped robot ascends the stairs. This means that a biped robot can climb up a higher step. The stairs walking trajectory that is separated into a ankle trajectory and a pelvis trajectory is generated by cubic spline interpolation. Finally, we confirm the feasibility of the proposed algorithm through the computer simulation and the real walking experiment.

• 한국정밀공학회지
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• 제23권4호
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• pp.75-82
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• 2006

In this paper, we propose an optimal trajectory for biped robots to move up-and-down stairs using a genetic algorithm and a computed-torque control for biped robots to be dynamically stable. First, a Real-Coded Genetic Algorithm (RCGA) which of operators are composed of reproduction, crossover and mutation is used to minimize the total energy. Constraints are divided into equalities and inequalities: Equality constraints consist of a position condition at the start and end of a step period and repeatability conditions related to each joint angle and angular velocity. Inequality constraints include collision avoidance conditions of a swing leg at the face and edge of a stair, knee joint conditions with respect to the avoidance of the kinematic singularity, and the zero moment point condition with respect to the stability into the going direction. In order to approximate a gait, each joint angle trajectory is defined as a 4-th order polynomial of which coefficients are chromosomes. The effectiveness of the proposed optimal trajectory is shown in computer simulations with a 6-dof biped robot that consists of seven links in the sagittal plane. The trajectory is more efficient than that generated by the modified GCIPM. And various trajectories generated by the proposed GA method are analyzed in a viewpoint of the consumption energy: walking on even ground, ascending stairs, and descending stairs.

• 드라이브 ㆍ 컨트롤
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• 제13권4호
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• pp.52-58
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• 2016

The mechanical design for biped walking of a humanoid robot doing the Argentina Tango is presented in this paper. Biped walking has long been studied in the area of robotic locomotion. The aim of this paper is to implement an Argentina Tango dancer-like walking motion with a humanoid robot by using a trajectory generation scheme. To that end, this paper uses blending polynominals whose parameters are determined based on PSO (Particle Swarm Optimization) according to conditions that make the most of the Argentina Tango's characteristics. For the stability of biped walking, the ZMP (Zero Moment Point) control method is used. The feasibility of the proposed scheme is evaluated by simulating biped walking with the 3D Simscape robot model. The simulation results show the validity and effectiveness of the proposed method.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.199-200
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• 2010

• 한국지능시스템학회논문지
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• 제19권5호
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• pp.622-628
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• 2009

다족로봇이 보행하기 위해서는 기본적으로 어떤 보행 패턴의 설정이 필요하다. 이러한 관점에서 어떤 보행 패턴이 효과적인 다족 보행을 가능하게 할 것인지를 분석하기 위하여 본 논문은 네 개의 다리를 이용하는 4족 보행 로봇 모델을 고려하며, 보행 순간마다 지지판에 의해 형성되는 지시다각형의 중심경로를 기반으로 보행 밸런스를 분석한다. 또한, 다족 로봇의 보행 밸런스를 평가하기 위한 성능지수를 제안한다. 시뮬레이션을 통하여, 4족 로봇의 보행에서 지지다각형의 중심 경로와 보행 밸런스는 사용된 보행 패턴에 따라 다르다는 사실을 보인다. 결과적으로, 보행 밸런스 지수와 생체모방 관점으로부터 4족 로봇의 보행을 위하여 유용한 보행 패턴을 제시한다.

• 로봇학회논문지
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• 제1권2호
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• pp.197-202
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• 2006

We present the synergy effect of humanoid robot walking down on a slope and support vector machines in this paper. The biped robot architecture is highly suitable for the working in the human environment due to its advantages in obstacle avoidance and ability to be employed as human substitutes. But the complex dynamics in the robot and ground makes robot control difficult. The trajectory of the zero moment point (ZMP) in a biped walking robot is an important criterion used for the balance of the walking robots. The ZMP trajectory as dynamic stability of motion will be handled by support vector machines (SVM). Three kinds of kernels are also employed, and each result from these kernels is compared to one another.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
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• pp.138-140
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• 2004

This paper mainly deals with the dynamic walking of a biped robot. At first, in order to walk in various environments, it is desirable to adapt to such ground conditions with a suitable foot motion, and maintain the stability of the robot by a smooth hip motion. A method to plan a walking pattern consisting of a foot trajectory and a hip trajectory is presented. The effectiveness of the proposed method is illustrated by simulation results. Secondly, the paper brings forward a balance control technique based on off-line walking pattern with real-time modification. At last, the concept of Zero Moment Point (ZMP) is used to evaluate dynamic stability.

• 제어로봇시스템학회논문지
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• 제17권10호
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• pp.1029-1036
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• 2011

An energy-efficient reference walking trajectory generation algorithm is suggested utilizing allowable ZMP (Zero-Moment-Point) region, which maxmizes the energy efficiency for cyclic gaits, based on three-dimensional LIPM (Linear Inverted Pendulum Model) for biped robots. As observed in natural human walking, variable ZMP manipulation is suggested, in which ZMP moves within the allowable region to reduce the joint stress (i.e., rapid acceleration and deceleration of body), and hence to reduce the consumed energy. In addition, opimization of footstep planning is conducted to decide the optimal step-length and body height for a given forward mean velocity to minimize a suitable energy performance - amount of energy required to carry a unit weight a unit distance. In this planning, in order to ensure physically realizable walking trajectory, we also considered geometrical constraints, ZMP stability condition, friction constraint, and yawing moment constraint. Simulations are performed with a 12-DOF 3D biped robot model to verify the effectiveness of the proposed method.

• 한국지능시스템학회논문지
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• 제16권4호
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• pp.443-448
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• 2006

본 논문에서는 이족 로봇 보행 중 전력 소비가 적고 안정한 저전력 보행 궤적 생성 방법을 재안하고, 생성된 보행 궤적의 구현을 위해 25 자유도를 갖는 이족 로봇을 설계 제작하였다. 본 논문에서 제안된 방법에서는 발목 사용 보행의 장점을 이용하고 보행 중 무릎을 크게 굽히는 동작을 줄이기 위해 기존 보행 방법과는 달리 우선 가장 안정한 VPCG 궤적을 생성 하고 생성된 궤적에 따른 발목과 골반의 보행 궤적을 생성한다. 이와 같이 함으로써 이족 로봇이 보행 중 항상 무릎을 굽히지 않으므로 전체 보행 중 전력 소비를 최소화 한다. 한편 제작된 이족 로봇은 발목 사용 시 지면과 잘 접지되는 발 구조와 골반을 유연하게 동작 할 수 있는 특징을 가진다. 마지막으로 이족 로봇의 실제 보행 실험 및 소비 전력 측정 결과, 본 논문에서 제안된 방법이 발목을 사용하지 않는 기존 방법에 비해 더 안정하고 전력 소비가 더 적음을 확인할 수 있었다.

• 제어로봇시스템학회논문지
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• 제8권10호
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• pp.890-897
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• 2002

This paper deals with the reduction of trajectory tracking error by changing the initial postures of a biped robot. Gait of a biped robot depends on the constraints of mechanical kinematics and the initial states including the posture. Also the dynamic walking stability in a biped robot system is analyzed by zero moment point(ZMP) among the stabilization indices. Path trajectory, in which knee joint is bent forward like human's cases, is applied to most cases considered with above conditions. A new initial posture, which is similar to bird's gait, is proposed to decrease trajectory tracking error and it is verified through real experimental results.