Yasuharu Kunii

Small, light-weight rover “Micro5” for lunar exploration

Abstract This paper describes a newly developed rover with small size, lightweight, low power consumption. Unmanned mobile robots for surface exploration of the moon or planets have been extensively studied and developed. A lunar or planetary rover is required to travel safely over a long distance for many days in unfamiliar terrain. This paper presents exploration mission, scientific signification, requirements, and technology of a lunar rover. This paper proposes a new mobility system, which has four wheels and one supported wheel. This novel suspension system is a simple and light mechanism like a four-wheeled rover and provides a high degree of mobility like a six-wheeled rover. Multiple rovers exploration by buddy system is also discussed. The performance of the developed rover is shown by some experiments.

Dynamic force simulator for force feedback human-machine interaction

A dynamic force simulator (DFS) for force feedback in human-machine systems is proposed. The DFS simulates object dynamics contact model and friction characteristics of the human hand interacting with objects in a virtual reality environment. After derivation of kinematic and force relations between hand and object space, a method is proposed for calculation and feedback of appropriate forces to the force controlled actuators of the sensor glove which has been developed.<<ETX>>

Tele-handshake using HandShake Device

In this paper the authors propose a one degree-of-freedom master-slave system called the HandShake device (HSD). HSD is composed of two systems: one is a master system, which is grasped by an operator; the other is a slave system, which grasps an operators palm. Two HSDs are respectively placed in a local site and a remote site so that people can physically communicate with each other through HSDs. HSD applies the virtual model method as the algorithm of teleoperation (tele-handshake).

Development of 20 DOF glove type haptic interface device-Sensor Glove II

Summary form only given. We present Sensor Glove II (SGII), a multi-DOF haptic interface, which has 20 degrees-of-freedom. Each joint is driven by an actuator through wire transmission. We measure joint angles by rotary encoders and torques of human fingers by strain-gauges as the stress of links. The operator can interact with the virtual environment simulator by this device. It is also used for teleoperation or telerobotics. The intention is not only that SGII should be used for telecontrol but also that the robot should learn human skills, and so perform more dextrous and intelligent manipulation. SGII acquires information about the complicated movements and forces of human fingers. It is the first step in the development of the Intelligent Assisting System (IAS).

Intelligent cooperative manipulation system using dynamic force simulator

Intelligent cooperative manipulation is proposed as a new paradigm for human-machine interaction and cooperation. Aiming at intelligent assistance of human operators the information and power flow between operator-system-task environment is carefully analyzed using a virtual reality to simulate the task environment. Central issue of this virtual reality is the dynamic force simulator (DFS) for feedback force calculation proposed in this paper. The DFS simulates object dynamics, contact model and friction characteristics of the human hand interacting with objects in the virtual reality. An example shows the efficiency of the proposed realization scheme of the DFS.<<ETX>>

Path planning for newly developed microrover

This paper describes the path planning method for a planetary microrover. A planetary rover is required to travel safely over a long distance for many days in unfamiliar terrains. Hence it is very important how a planetary rover processes sensory information in order to understand the environment and to make decisions. The authors have newly developed a small rover for future lunar or planetary exploration. As a new data structure for map information, an extended elevation map is introduced, which includes the effect of the size of the rover. The proposed path planning can be conducted in such a way as if the rover were a point while the size of the rover is automatically taken into account. The map obtained by sensors includes uncertainties. Thus a path planning scheme based on traversability and probability is also proposed. The validity of the proposed method is verified by computer simulations.

Accuracy improvement of Shadow Range Finder: SRF for 3D surface measurement

In planetary exploration, when collecting a rock, it is important how to get information of the surface around a sample. Usually, surface information is brought by a special sensor such as laser range finder and stereo camera. These sensors, however, need more weight and power consumption and are used for only one function such as the surface measurement. And furthermore, there are some difficulties to use those sensors in some situation, for example, a high brightness environment. In this research, we apply Shadow Range Finder: SRF, which can make good use of a shadow for the measurement of surface information under the direct sunlight. SRF is robust for above-mentioned environment, and a shadow would be recognized in the case of a halation. The measurement by SRF uses a single camera installed on a manipulator, and a link of a manipulator, which produce its shadow. The principle of SRF is same as laser range finder, and a shadow is used for scanning slit instead of a laser. In this paper, experimental results of actual objects are shown, and we discusses about accuracy improvement for measurement data, considering an umbra and a penumbra caused by surface light source. Finally, we apply this method to tele-sampling by a manipulator on a rover system.

Scientific exploration of lunar surface using a rover in Japanese future lunar mission

Abstract A new lunar mission (SELENE-B) including a lander is now in consideration in Japan. The mission will follow up SELENE (SELenological and ENgineering Explorer, a global remote sensing mission of the moon in 2004). Scientific investigation plans using a rover are proposed: exploration of a crater central peak to discover subsurface materials and exploration of the polar region to discover the trapped ice. We have already developed a 5-wheel engineering-model rover, Micro5, which has a long manipulator with a camera on top. The rover can climb over 15cm steps and rocks by a new suspension system PEGASUS.

A low-cost real-time stereo vision system for looking at people

Real-time computer vision systems that observe the actions of people have received increasing attention as they are important for a broad range of applications. Examples are intelligent man-machine interfaces or intelligent rooms that have the capability to understand the actions of their inhabitants. In this paper we present the design of a stereo vision system for the precise and robust real time tracking of human hands and heads that unlike previous systems uses low-cost industry standard components. The system uses color and motion information to find the human. Using previously calibrated cameras the 3D positions of hands and head are calculated. Because of its client-server architecture the system is scalable to an arbitrary number of cameras and application processes. Experimental results for the performance of the system are given.

Tele-driving system with command data compensation for long-range and wide-area planetary surface explore mission

We discuss a tele-driving method for long-range driving of a lunar rover. An operator uses a virtual world simulator to make a command path. The virtual environment of this simulator is constructed with measurement data from a rover on the moon. We have, however, a communication delay between the earth and the moon. So, there is a difference between old map data which the operator used for path planning and new data, which a rover is tracking on. The operators path command has less reliability for avoiding obstacles and to reach the goal. Therefore, to make the operators command highly reliable, we propose Command-Data Compensation, which compensates this difference as the distortion of the environmental map.