We present a real-time algorithm which can recover the 3D trajectory of a monocular camera, moving rapidly through a previously unknown scene. Our system, which we dub MonoSLAM, is the first successful application of the SLAM methodology from mobile robotics to the "pure vision" domain of a single uncontrolled camera, achieving real time but drift-free performance inaccessible to structure from motion approaches. The core of the approach is the online creation of a sparse but persistent map of natural landmarks within a probabilistic framework. Our key novel contributions include an active approach to mapping and measurement, the use of a general motion model for smooth camera movement, and solutions for monocular feature initialization and feature orientation estimation. Together, these add up to an extremely efficient and robust algorithm which runs at 30 Hz with standard PC and camera hardware. This work extends the range of robotic systems in which SLAM can be usefully applied, but also opens up new areas. We present applications of MonoSLAM to real-time 3D localization and mapping for a high-performance full-size humanoid robot and live augmented reality with a hand-held camera

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MonoSLAM: Real-Time Single Camera SLAM

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.

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

From exploring planets to cleaning homes, the reach and versatility of robotics is vast. The integration of actuation, sensing and control makes robotics systems powerful, but complicates their simulation. This paper introduces a versatile, scalable, yet powerful general-purpose robot simulation framework called V-REP. The paper discusses the utility of a portable and flexible simulation framework that allows for direct incorporation of various control techniques. This renders simulations and simulation models more accessible to a general-public, by reducing the simulation model deployment complexity. It also increases productivity by offering built-in and ready-to-use functionalities, as well as a multitude of programming approaches. This allows for a multitude of applications including rapid algorithm development, system verification, rapid prototyping, and deployment for cases such as safety/remote monitoring, training and education, hardware control, and factory automation simulation.

V-REP: A versatile and scalable robot simulation framework

It is known that for a large magnitude push a human or a humanoid robot must take a step to avoid a fall. Despite some scattered results, a principled approach towards "when and where to take a step" has not yet emerged. Towards this goal, we present methods for computing capture points and the capture region, the region on the ground where a humanoid must step to in order to come to a complete stop. The intersection between the capture region and the base of support determines which strategy the robot should adopt to successfully stop in a given situation. Computing the capture region for a humanoid, in general, is very difficult. However, with simple models of walking, computation of the capture region is simplified. We extend the well-known linear inverted pendulum model to include a flywheel body and show how to compute exact solutions of the capture region for this model. Adding rotational inertia enables the humanoid to control its centroidal angular momentum, much like the way human beings do, significantly enlarging the capture region. We present simulations of a simple planar biped that can recover balance after a push by stepping to the capture region and using internal angular momentum. Ongoing work involves applying the solution from the simple model as an approximate solution to more complex simulations of bipedal walking, including a 3D biped with distributed mass.

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Capture Point: A Step toward Humanoid Push Recovery

For 3D walking control of a biped robot we analyze the dynamics of a 3D inverted pendulum in which motion is constrained to move along an arbitrarily defined plane. This analysis yields a simple linear dynamics, the 3D linear inverted pendulum mode (3D-LIPM). Geometric nature of trajectories under the 3D-LIPM and a method for walking pattern generation are discussed. A simulation result of a walking control using a 12-DOF biped robot model is also shown.

The 3D linear inverted pendulum mode: a simple modeling for a biped walking pattern generation

This paper introduces a framework for the remote execution of whole body motions for humanoid robots Humanoid robots are biped machines which usually possess more than 20 degrees of freedom(D0F) The complexity of their multi-DOF structure and the difficulty in maintaining postural stability make the whole body operation of humanoid robots fundamentally different from traditional fixed-base manipulators or stable-base mobile manipulators Getting hints from human conscious and subconscious motion generations, we propose a method of generating whole body motions which integrates operator?s command input and the robot?s autonomous functions Instead of giving commands to all joints all the time, the operator selects only the necessary points of the humanoid robot?s body for manipulation This paper first explains the concept of the system and the framework for integrating operator?s command and autonomous functions in whole body motion generation Using the framework, we constructed autonomous functions for maintaining stability constraint while satisfying the desired trajectory of operation points and a workspace extension autonomy which changes utilization of body parts Finally the paper reports on the implementation of the proposed method to teleoperate a 30 DOF humanoid robot HRP-2 using only two 3 DOF joysticks Experiments teleoperating HRP-2 confirmed the effectiveness of the proposed method

A framework for remote execution of whole body motions for humanoid robots

Biped-type leg-wheeled robot Osamu Matsumoto a , Shuuji Kajita b , Muneharu Saigo c & Kazuo Tani d a Mechanism Division, Robotics Department, Mechanical Engineering Laboratory, 1-2 Namiki, Tsukuba, Ibaraki 305-8564, Japan b Mechanism Division, Robotics Department, Mechanical Engineering Laboratory, 1-2 Namiki, Tsukuba, Ibaraki 305-8564, Japan c Mechanism Division, Robotics Department, Mechanical Engineering Laboratory, 1-2 Namiki, Tsukuba, Ibaraki 305-8564, Japan d Department of' Information Science, Gifu University 1-1 Yanagido, Gifu 501-1193, Japan Published online: 02 Apr 2012.

Biped-type leg-wheeled robot

A motion planner of emergency stop must make an operating humanoid robot to a stationary state under the emergency signal. It plays an important role in prevention of falling over because humanoid robots fall over easily. Immediately after the emergency signal, it must generate the emergency stop motion in real-time. We modeled a humanoid robot as a simple dynamic system consists of ZMP (Zero-Moment Point) and COG (Center of Gravity) as its states. The emergency stop motion is generated by a state feedback. We determined optimal feedback gains in terms of the initial conditions and the pole assignment. The proposed method realized a reliable emergency stop with low computational cost. Furthermore, it can easily predict the possibility of the successful emergency stop at any time. The validity of the proposed method is confirmed by an experiment using humanoid robot HRP-2.

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Motion Planning of Emergency Stop for Humanoid Robot by State Space Approach

https://www.jstage.jst.go.jp/article/sicetr1965/31/10/31_10_1705/_pdf

Dynamic Biped Walking Control on Rugged Terrain Using the Linear Inverted Pendulum Mode

For the control of a dynamic mobile robot, the attitude in gravity space is an important state of the robot Usually, the attitude is difficult to detect by simply using the signals from sensors For example, an external sensor contacting the ground suffers disturbances from the roughness of the ground; the integration of a gyroscope signal has the problem of drift; an inclination sensor does not indicate the direction of gravity when acceleration exists To solve these problems, we propose a control method in which the attitude of a mobile robot is estimated by an observer considering the robot dynamics and using only the information obtained by internal sensors We applied this method to a wheeled inverted pendulum as an example of a dynamic mobile robot The estimation of the attitude was made with good accuracy using the signals from the rate gyroscope and the motor encoder, and the control of stable running of the pendulum on a flat level plane worked successfully We also realized the running contro

Shuuji Kajita

Papers

A framework for remote execution of whole body motions for humanoid robots

Biped-type leg-wheeled robot

Motion Planning of Emergency Stop for Humanoid Robot by State Space Approach

Dynamic Biped Walking Control on Rugged Terrain Using the Linear Inverted Pendulum Mode

Estimation and control of the attitude of a dynamic mobile robot using internal sensors