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In this paper, a navigation and environment mapping method is presented for small exploration robots that use hopping motion. While previous research about hopping rovers mostly focuses on mobility and mechanical design, the motivation for the proposed method is to provide a fully autonomous navigation system using only a monocular camera. The method accurately estimates the hopping distance and reconstruct the 3D environment using Structure from Motion, proving that a monocular system is not only feasible, but accurate and robust at the same time. The relative scale problem of the reconstructed scene and trajectory is solved by the known gravity and parabolic motion constraints. After each hop, the error in landing position is corrected by a modified Iterative Closest Point algorithm with non-overlapping part elimination. The environmental point cloud is projected onto a 2D image, that is used to find the most suitable landing position for the next hop using protrusion based obstacle detection, and navigate the robot towards the goal direction. Both virtual environment simulations and real experiments confirm the feasibility and highlight the advantages of the presented method.

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In this paper a navigation method is presented for space exploration robots using hopping motion in environments with large elevation differences. A monocular camera system is used to reconstruct the flight trajectory and environment around the robot using Structure from Motion while traveling. The created environmental point cloud is projected to 2D to create a variable resolution image and image processing is used to find the most suitable position for the next landing based on normals with the help of gradient maps and error estimation. The method is evaluated in a simulation environment against the previously used protrusion based method to show that the proposed system can extend the operation of the robot to terrains with large elevation differences while still successfully avoid obstacles and dangerous areas.

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The SELENE-B, a lunar landing mission, has been studied in Japan, where a scientific investigation plan is proposed using a robotic rover and a static lander. The main theme to be investigated is to clarify the lunar origin and evolution, especially for early crustal formation process probably from the ancient magma ocean. The highest priority is placed on a direct in situ geology at a crater central peak, “a window to the interior”, where subcrustal materials are exposed and directly accessed without drilling. As a preliminary study was introduced by Sasaki et al. [Sasaki, S., Kubota, T., Okada, T. et al. Scientific exploration of lunar surface using a rover in Japanse future lunar mission. Adv. Space Res. 30, 1921–1926, 2002.], the rover and lander are jointly used, where detailed analyses of the samples collected by the rover are conducted at the lander. Primary scientific instruments are a multi-band stereo imager, a gamma-ray spectrometer, and a sampling tool on the rover, and a multi-spectral telescopic imager, a sampling system, and a sample analysis package with an X-ray spectrometer/diffractometer, a multi-band microscope as well as a sample cleaning and grinding device on the lander.

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.

In recent years, many researchers have studied and developed lunar or planetary rovers for unmanned surface exploration. By the way, mission scope of a lander, which does not have mobility, is just a point. If we can have a rover, this mission area can be expanded to two-dimensional mission area. The object of a rover mission is scientific investigation, therefore, a rover system is not a mobile engineering system but a part of scientific equipments. A manipulator has strong possibility to be one of the scientific equipments mounted on a rover. In this paper, we introduce a micro-rover called “Micro5” which has a new suspension system: PEGASUS for high-mobility performance; we discuss a manipulator for this rover and introduce a developed micro-manipulator. It has five degrees of freedom and each joint is driven by an ultra-sonic motor which needs no electrical power to keep a posture of the manipulator. The manipulator is operated with a virtual world simulator and images sent from a hand eye camera by a joystick located on a remote site.

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.

Considering that the robots work in real environment, it is very important to recognize its condition by itself. Therefore, we are developing a self-diagnosis system for the autonomous robots. Especially, in this paper, we develop the basic sensory system and self-diagnosis method of an autonomous mobile robot. At first, we discuss the definition and classification of system accident. We also propose actual algorithm and method to diagnosis internal status of the robot using sensory information. The developed sensory system for self-diagnosis consists of multiple sensors, which are equipped on input/output node of each component. We show some experimental result using real autonomous mobile robot and our proposed diagnosis algorithm.

We developed a lightweight, low-power microrover for surface exploration in space. Such a rover must travel safely over long distances and periods in unfamiliar terrain. We present an exploration mission, scientific significance, requirements, and technology of a rover, proposing mobility using 4 wheels and 1 supported wheel whose suspension is simple and light and as mobile as a 6-wheeled rover.

In this paper, we describe a basic sensing system for self-diagnosing an autonomous mobile robot. In recent years, many researches on intelligent robots and systems have been done. But, when such robots and systems work in the real environment, it is important for those robots and systems to have the ability to recognize their own conditions for detecting faults. On the point of view, we should consider pay more attention to diagnose in such intelligent systems. Therefore we try to construct an internal sensing system as a self-diagnosis system on a real robot. Especially, in this paper, we discuss about motor system of an autonomous omnidirectional mobile robot, which was developed in RIKEN. The self-diagnosis system consists of multiple sensors, which are voltage, current, encoder, and magnetic sensors. We show some diagnosing experimental results using the real system. From the results, we could collect basic data for fault detection of the system.

This paper presents a new type of human interface with force feedback attached to an arm, which we named Sensor Arm. The Sensor Arm can be utilized as an interface for interactive communication with the virtual environment and as a master manipulator of a tele-operation system. The number of degrees-of-freedom (DOF) of the Sensor Arm is seven, which is the same DOF of a human arm. Angle and torque of each joint can be measured. Moreover, in this system, force feedback can be realized at each joint of the human arm. To measure human force a new type of force sensor system is proposed in the Sensor Arm system.

In this paper, a new haptic human interface device to communicate with a virtual world, which we named Sensor Glove II (SGII), is presented. SGII, which is drawn on the human hand, corresponds to the dexterous manipulation of human fingers and acquires angles and torque of each joint. SGII adds the reaction forces of a virtual object to the fingers. The forces are calculated in the Dynamic Force Simulator we have developed. We outline the design, characteristics and structure of SGII, and display preliminary experimental result to verify the stability and performance of SGII.

In this paper, the authors present a dynamic force simulator (DFS) for force feedback in human-machine systems. They propose a virtual world model with two force flows: one is the force flow from human to an object, the other is the force flow from an object to human. To use this model, the DFS simulates object dynamics, contact models, and friction characteristics of the human hand interacting with the object in virtual reality. After the derivation of kinematic and force relations between hand and object space, they balance the two forces: one from the human and the other from the object in the contact force space in virtual world and then realize the adequate feedback forces to human operator. Interaction with the DFS allows calculation and feedback of appropriate forces to the force controlled actuators of the sensor glove they have developed. In this paper grasping of a cylinder in the virtual world is presented. During object grasping, they measure joint angles and torques using the sensor glove system. In the future, they will use this system to analyze human dextrous manipulations called human skill.

The approach presented in this paper is based on two ideas : (1) on the planning level an electrostatic potential field in the configuration space of the robot-manipulator is used. The generalized force curves are attractive to the goal point avoiding obstacles without local minima ; (2) on the control level the system follows these force curves using sliding mode control. The system is attracted to the swishing manifold using sliding mode and therefore the system is robust to disturbances and parameter variations.