Shunsuke Komizunai

Humanoid robot motion generation for nailing task

In order to exert a large force on the environment, it is effective to apply impulsive force. We describe the motions that perform tasks by applying impulsive force as ldquoimpact motionrdquo. In this research, a nailing task is taken as an example of impact motion. This paper proposes a way to generate impact motions for humanoid robots to exert a large force and the feedback control method for driving a nail robustly. In order to validate the proposed scheme, experiments are carried out using life-sized humanoid robot HRP-2. The motion for nailing task generated by the proposed method is compared with the motion designed heuristically by a human. The driving depth is clearly increased by the proposed method.

A Human-Like Approach Towards Humanoid Robot Footstep Planning

Humanoid robots posses the unique ability to cross obstacles by stepping over or upon them. However, conventional 2D methods for robot navigation fail to exploit this ability and thus design trajectories only by circumventing obstacles. Recently, global algorithms have been presented that take into account this feature of humanoids. However, due to high computational complexity, most of them are very time consuming. In this paper, we present a novel approach to footstep planning in obstacle cluttered environments that employs a human-like strategy to terrain traversal. Design methodology for obstacle stepping over motion designed for use with this algorithm is also presented. The paper puts forth simulation results of footstep planning as well as experimental results for the stepping over trajectory designed for use with hardware execution of the footstep plan.

Development of a static sinkage model for a biped robot on loose soil

This paper addresses the development of a dynamics simulator that for a biped robot on loose soil. Especially, the paper focuses on the method of sinkage calculation which is one of the characteristics for walking on loose soil. The calculation algorithm is changed dynamically according to the support condition of the legs. Considering ground projection of center of mass (GCoM) as a center of rotation of a robot, angle of trim is also estimated. Additionally, to describe the dynamical variation of sinkage, a filtering method is proposed for the calculation result. By applying the proposed method, sinkage phenomenon of a biped robot during stepping is simulated realistically.

Symmetry cooperative object transportation by multiple humanoid robots

This research aims to create a framework of transporting an object by multiple humanoid robots. In this work, a symmetric hybrid position/force control is adapted to two humanoid robots. The reference object position and attitude are given by an operator online, and the two humanoid robots generate its whole body motion to follow the reference object position properly. The result of proposed method is verified with a dynamics simulation.

Analysis of nailing task motion for a humanoid robot

In order to exert a large force on the environment, it is effective to apply impulsive force. We describe the motions that perform tasks by applying impulsive force as ldquoimpact motionrdquo. In this research, a nailing task is taken as an example of impact motion. This paper presents a relationship between driving depth and force or impulse and analysis of impulsive force prediction model.

Implementation of HOAP-2 Humanoid Walking Motion in OpenHRP Simulation

This paper describes the implementation of walking motion of HOAP-2 Humanoid in OpenHRP simulation. Weput forward the existing knowledge on humanoid walking in aconcise and straightforward manner and integrate it to make the humanoid walk. We make use of the concept of Zero Moment Point (ZMP) for stability analysis and Cart Table Model to determine the relation between Zero Moment Point and Centre of Mass for generating a walking motion pattern. The walking motion pattern is generated in Matlab which is then fed to OpenHRP simulation to test stable walking of the humanoid. The paper also discusses some stabilization algorithms which have been implemented on the humanoid in order to account for variations like surface unevenness and backlash which are encountered by the humanoid during walking in the real world.

An Impact Motion Generation Support Software

When a robot applies force statically on a target object, magnitude of the force is limited by the maximum force or torque of the actuators. In order to exert a large force on the target beyond this limitation, it is effective to apply impulsive force. We describe the motions that perform tasks by applying impulsive force as “impact motion.” There are difficult problems introduced by impacts between a robot and a target. Uchiyama proposed a control algorithm constitution method and dynamic control modes for performing a nailing task by a 3 DOF manipulator (Uchiyama, 1975). Zheng and Hemami discussed mathematical modelling of a robot that collides with the environment (Zheng & Hemami, 1985). Asada and Ogawa proposed the virtual mass for analyzing dynamic behaviour of a manipulator arm and its end effecter that interacts with the environment (Asada & Ogawa, 1987). Around the same time, Khatib and Burdick proposed the effective mass (Khatib & Burdick, 1986). Walker investigated the effect of different configurations of kinematically redundant arms with impact force at their end effectors during contact (Walker, 1994). These works mentioned above used rigid robotic manipulators fixed on the ground. Yoshida and Sashida investigated impact dynamics in free-floating multibody systems in space (Yoshida & Sashida, 1993). Lew discussed about contact force control of a long-reach flexible micro/macro manipulator (Lew, 1997). These studies focused on trying to minimize the impulsive force since the force causes fatal problems in a space robot or a flexible arm. A few attempts on tasks applying impulsive force by a humanoid robot have been reported in recent years. Arisumi et al. discussed a motion generation method for dynamic lifting by a humanoid robot based on a planar model (Arisumi et al., 2007). The strategy for lifting is based on centre of percussion for maintaining stability. The main goal of our research is to develop a scheme to generate an optimal humanoid robot’s impact motion for a given task considering multibody dynamics. To effectively generate impact motion, impact motion generation software is developed as the first step of the impact motion research. The developed impact motion generation support software visualizes not only a designed motion but also an experimented motion. Force and torque measured in experiments are visualized on the experimented motion. The visualized ZMP (Zero-Moment Point) (Vukobratovic et al., 1990), GCoM (Ground Projection of the Center of Mass), force, moment 11

Development and Evaluate of a Multi Degree of Freedom Mid-air Force Display Device by using Vibrators

仮想現実 (VR) や拡張現実 (AR) 体験をより豊かにするため に,力触覚フィードバックを与える手法が研究されている.力触 覚フィードバックを与える手法は,大きく分けて,知覚原理の観 点から実際に力を作用させるか錯覚を利用するか,装置実装の観 点から環境固定型・装着型・非接触型などと区分できる.雨宮ら は,小さな加速度と大きな加速度の組み合わされた振動を用いて リニア型振動子に特定の周波数,デューティ比の信号を入力する ことで擬似力覚を得られることを報告している [1, 2] .Tanabe らは,雨宮らの原理を用いた非接地での力覚提示に,振動スピー カを用いた [3, 4].また,振動子を 2 個用い,並進の擬似力覚 を組み合わせて回転の擬似力覚を生じさせる手法を開発した [5]. この手法で用いる振動スピーカ)は入力信号によって振動を制御 でき,提示する力覚の大きさを変化させるような使い方も可能で ある. 擬似力覚の利点として,支点の反作用を考慮せず並進方向に連 続的に力覚を提示できる点が挙げられる.本論文では,空中で並 進 3 自由度・回転 3 自由度の力覚提示が可能な把持型力覚提示 装置の開発を目指し,その基礎研究として並進 2 自由度・回転 2 自由度の装置を開発・評価する.振動子を用いた疑似力覚によ る牽引感覚の提示を基本とし,新たに提案する振動子の向きを変 えられる機構を導入することで,振動子の数を増やすことなく自 由度を拡張する.これにより,装置規模・重量・消費電力が単調 増加することを避け,把持しやすい装置設計を可能とする.ユー ザテストにより開発した装置による提示感覚の識別可能性を評価 する.

Evaluation of ease of target position recognition in interaction with midair images by using mist screen

This paper described a interaction system with midair images projected by using mist screen. In comparison with the previously developed system, the new system has some advantages as follows: visibility and presence of midair images, tracking accuracy of a finger tip, interactivity with midair images. In the system, three new components: a high-power mist screen generation device, an accurate hand motion tracking method and a proper screen surface calibration algorithm are introduced. These advantages enhance quality of experience in interaction with midair images and enable quantitative evaluation of performance of the system. In the results of user evaluation test, positions of a CG object as midair image and users finger tip are well corresponding. These results indicate that, position of midair images in the system can be recognized easily, and the system shows excellent performance as a midair image display system.

1P1-W09 Development of a Fingertip Tactile Device using a 3 DoF Parallel Mechanism with Vertical Fixed Linear Actuators

インタラクティブで質の高い仮想体験を実現するためには,高 い没入感が得られる視覚提示とともに,力触覚を提示すること が効果的である.ここでは特に,指先における表皮感覚 (触覚) の提示に着目する.装着型の触覚提示装置は,タッチパネルのよ うな設置型装置に比べてユーザの触行動を制約せず,非接触型装 置 [1] と比べて圧覚などの大きな接触力を提示可能である. 装着型装置の一つとして,ベルトを巻き上げることで指先に 触覚を提示する手法が提案されている [2, 3].この手法では,圧 覚だけでなくせん断感覚や振動,さらには把持対象物の重量感な ど,様々な感覚が提示可能である.しかし,接触子がベルトであ るため提示可能なせん断感覚は一方向に限られていた. 本論文では,小型の 3 自由度直動パラレル機構を利用した装 着型指先触覚提示装置について述べる.本装置は,指先に圧覚と 二方向のせん断感覚およびある程度の振動を提示する.本装置の 構造と触覚提示原理について説明する.また,機構解析に基づい て可動範囲や可操作性の観点から動作性能を評価する.