In this study, we defined a proximity sensor based on the fusion of an optical reflection intensity sensor and optical time-of-flight (ToF) sensor as a wide-range precise proximity sensor (WrPPS). This sensor can detect objects over a wide range, has low dependence on the physical properties of the detected object, and can be configured in a compact form. To allow the broad application of this sensor, we propose a WrPPS Single Board that packages the minimal configuration of this sensor onto a compact printed circuit board, allowing applications wherever this board can be mounted. Furthermore, to improve the accessibility of this board and allow easy application by anyone, we sell the board at a low price and release the fusion software for the intensity and ToF sensors as open-source software. The distance measurement accuracy of this sensor was quantitatively evaluated through experiments involving variations in the reflective properties, shape, and pose of the measurement target. To demonstrate the wide applicability of this sensor, we present examples of its applications, including grasping of compliant objects, tactile sensing in a stuffed robot, slip detection during walking, and agricultural plant sensing.

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