Precision Flight Drones with RTK-GNSS

An RTK-GNSS was introduced to realize the precision flight of a drone system for transporting harvested loquats and spraying pesticides to suppress the rotting of fruits. Transportation and spraying experiments were conducted. Precision automatic navigation flights were realized in transportation experiments. In addition, precision landing was performed within approximately 10 cm of the target position. Sufficient spraying flights were performed during the spraying experiment.

Visual Monocular Localization, Mapping, and Motion Estimation of a Rotating Small Celestial Body

In the exploration of a small celestial body, it is important to estimate the position and attitude of the spacecraft, as well as the geometric properties of the target celestial body. In this paper, we propose a method to concurrently estimate these quantities in a highly automatic manner when measurements from an attitude sensor, inertial sensors, and a monocular camera are given. The proposed method is based on the incremental optimization technique, which works with models for sensor fusion, and a tailored initialization scheme developed to compensate for the absence of range sensors. Moreover, we discuss the challenges in developing a fully automatic navigation framework.*

*This paper is an extended version of a preliminary conference report [1].

Development and Performance Evaluation of Planar Travel Distance Sensors for Mobile Robots in Sandy Terrain

A planar travel distance sensor (two-dimensional sensor) was developed for a mobile robot in sandy terrain. The sensor system uses an optical flow device integrated into a small module with a simple configuration. The system achieves a high sampling rate on the order of milliseconds as well as precise measurement on a sub-millimeter order. Its performance was evaluated experimentally for measurement accuracy and repeatability, velocity response, robustness at varied heights with respect to terrain, and terrain surface characteristics. The experimental results confirm that the two-dimensional sensor system is accurate, having an error of distance traveled of less than a few percent, and that it possesses a wide dynamic range for the robot’s traveling velocity. This paper also discusses the applicability of the two-dimensional sensor for practical scenarios on the basis of the experimental findings.

Development of Autonomous Robot with Simple Navigation System for Tsukuba Challenge 2015

[abstFig src='/00280004/01.jpg' width='300' text='MercuryMega (SICKLaser-Model)' ] This paper introduces the robot that was developed for Tsukuba Challenge 2015. One of the team’s design goals was to implement a simple sensor configuration and control algorithm. For example, the robot’s laser range finders (LRF) were of fixed type, and localization was accomplished using only a single LRF and no other sensor. Environment map matching was achieved using an algorithm that processed pyramid images using binary image processing to reduce computational cost. Shape information from the LRF and color information from a camera were combined to detect a signboard placed near a person. During an actual test in rainy weather, the robot ran the entire course and, detected two, out of a possible four, number of target persons.