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The potential exists for significantly reducing operating costs by minimizing missing and overlap in successive agricultural field operations, particularly in areas where the equipment is pull-behind and widths of over fifteen meters are common. This paper reports on the development of a sensor, consisting of a video camera and image processing system, to detect the location of the demarcation line between tilled-and-untilled soil and cut-and-standing crop. The development of hardware and software to achieve real-time operation under a variety of crop, soil and ambient lighting conditions is described.

On July 2nd, 1985 the Giotto spacecraft was launched from Kourou (French Guyana) towards its encounter with Halley’s comet on 13-14 March 1986. This first European Space Agency interplanetary spacecraft was spin stabilized and weighed 960 kg at launch. Giotto was injected into a heliocentric orbit involving variations of the solar intensity by a factor of two. This fact together with the communications requirements and comet encounter geometry restricted the spacecraft attitude such that during the 9 month mission all external surfaces were illuminated by the sun, imposing severe limitations on the use of any surface for efficient heat rejection. The spacecraft thermal control subsystem included several heater circuits and three “thermal shutters” operated by ground command. The daily configuration of these items was balanced between thermal and power requirements.