Abstract: A propelling apparatus includes a plurality of propellant cylinders series-connected to each other to be propelled by receiving a pushing force from behind, joints for series-connecting the propellant cylinders, a propellant head connected to a forward-most end of the propellant cylinders to be pressed into the earth, a leader member constituting a leading end of the propellant head, the leader member being rotatable about an axis of the propellant head by receiving a driving force from a driving device. An inclined pressure-receiving face is formed at a forward portion of the leader member for receiving an earth pressure in association with the underground propelling movement of the propellant head and steering the propellant head toward the direction of application of the earth pressure to the pressure-receiving face. The joint includes a flexible joint which is pivotally flexible about a transverse axis extending normal to an axis of the propellant cylinder.

Abstract: An underground propelling method uses a propellant apparatus including a propellant head having a pressure receiving face portion inclined relative to an axis of the head and a plurality of propellant cylinders flexibly and pivotally connected in series to a rear end of the propellant head. The propellant apparatus is propelled under the ground by applying a thrust to the propellant apparatus from behind. Each propellant cylinder of the apparatus is pivotal about a single pivot axis thereof alone. The apparatus is propelled with the pressure receiving face portion thereof being oriented along a pivotal direction of the propellant cylinder about the pivot axis.

Abstract: A harvesting apparatus for automatically removing fruit from its growth source comprising a harvesting hand mounted at a distal end of an articulated arm assembly, a video camera for picking up a fruit image, and a control unit for guiding the harvesting hand to the fruit in response to information provided by the video camera. The harvesting hand includes a vacuum pad for drawing and catching the fruit, and a calyx cutting device. The vacuum pad and cutting device are movable relative to each other between a first position in which the vacuum pad is disposed forwardly of the cutting device for approaching and drawing the fruit and a second position in which the cutting device is disposed forwardly of the vacuum pad for removing the fruit from its tree.

Abstract: A chroma keying generator apparatus is disclosed having a monitor camera transmitting color signals to multipliers for separating a luminance signal from an image signal and amplifying same by selected gain levels, comparison circuits for comparing two color signals with pre-selected reference levels therefor having upper and lower limits and producing outputs denoting that the ratio of the color signal to the luminance signal for a given color falls within a pre-selected reference range, and a gate circuit which evaluates the outputs from the comparison circuits to produce pulses representing a logical "1" when the output is within the reference range and a logical "0" when the output is not within the reference range.

Abstract: An automatic differential locking system for a working vehicle having steerable front and rear wheels, which includes a selector for selecting a steering mode of the vehicle, an actuator for operating a differential locking mechanism, and a gate for sending a control signal to the actuator in response to a signal received from the selector. The gate is adapted to send a differential locking signal to the actuator upon receipt of a parallel steering mode signal from the selector. In response to the differential locking signal the actuator actuates the differential locking mechanism. Since differential revolutions of the wheels are limited at times of parallel steering, the vehicle is capable of accurate course revisions and alterations without slipping.

Abstract: Apparatus and method for controlling an automatically running vehicle over a predetermined course which has guidelines intermittently placed therein. Vehicle commands used to negotiate the course under manual control are stored in a memory. The vehicle has sensors which detect the presence and location of the guidelines as the vehicle passes by. The vehicle travels the course under control of the stored vehicle commands until guidelines are detected indicating the vehicle is off course. Then, vehicle control is switched so that the vehicle returns on course, over the guidelines. When the guidelines are no longer detected, vehicle control is returned to the memorized vehicle commands in such a fashion as to synchronize the actual vehicle position with the memorized data.

Abstract: A fruit harvesting apparatus in which the positions of fruit are searched and detected by a television camera with a variable shooting direction. Both the television camera and a spot light emitting device, such as a laser, are varied in position and direction in accordance with instructions to locate a fruit. A movable fruit picker is then moved to the determined position of the fruit and operated to pick the fruit.

Abstract: A machine body inclination detector device for detecting change in position of a float with respect to a machine body according to the inclination of the machine body. The float is constructed such that the buoyancy of the float does not undergo a great change even though the liquid level is inclined.

Abstract: A tractor has a traction load sensing device needed for effecting regulation of the soil-engaging implement load. Sensor body of the traction load sensing device is accommodated in a casing establishing complete sealing or approximately establishing such state, and the casing is accommodated in and releasably secured to a transmission case of the tractor in an oil-tight manner.

Abstract: An automatic position control apparatus for a ground working vehicle equipped with a liftable working implement. The control apparatus is adapted to automatically control lifting and lowering of the implement so that the deviation of the draft value of the implement acutally detected by a draft detector from the draft value preset by a draft setting unit is maintained within a permissible range preset by a sensitivity setting unit. The control apparatus is characterized in that the apparatus includes a detector for detecting that the deviation is not decreasing outside the permissible range above the maximum permissible value thereof so as to automatically control the lift of the implement only while the deviation detector is in detecting operation.

Abstract: Load control for engine of vehicle for agricultural work with rotary working implement, for avoiding too much deviation of the working depth while preventing the engine from stopping under heavy overloading. The rotary working implement is automatically raised and lowered in accordance with the results of sensing the engine rotation and of the actual working depth. For prevention of the engine failure, the rotary working implement is unconditionally raised whenever engine rotation below a predetermined value is sensed.