fig1 - 3 depict a harvester machine that is improved by the inclusion of the automatic machine movement , tree sensing and shaking system of the present invention . fig1 is a perspective of view of the harvester machine , fig2 is a side elevational view thereof , and fig3 is a top plan view thereof . as depicted in fig1 - 3 , the harvester 10 includes a body 14 enclosing a drive engine , a forwardly disposed operator &# 39 ; s cab 18 , a tree clamping and shaking head 22 that is mounted to the body 14 such that the operator can view the tree clamping and shaking process , and a single front steering wheel 26 , mounted on a caster , for maneuvering the harvester 10 . the shaker head 22 is movably mounted upon an outwardly projecting support boom 30 , such that the harvester can be positioned next to a tree and the shaker head 22 then moved outwardly to clamp and shake the tree . the shaker head 22 includes two jaws 34 and 35 having shaking pads 38 and 39 that are used to clamp and shake the tree . in operation , the operator drives to the first tree and positions the shaker head 22 parallel to the tree row , aligning shaker head 22 with the first tree to be shaken . sensor a , 50 - 51 , detects the presence and location of the first tree . the operator then presses a button on the joystick in the cab to start the automatic cycle of steps . support beam 30 moves out towards the tree . as the shaker 22 goes through its cycle , sensor d , 52 will measure the distance to the tree . the measurement takes place as shaker head 22 extends to the tree . shaker head 22 stops when a beam between sensors 50 and 51 is broken by the tree . jaws 34 and 35 clamp and shake the tree and then unclamp the tree and move back to the harvester 10 . the length of time that the tree is shaken is predetermined and set in the controller ( plc ). when shaker 22 has completed shaking the tree and retracts , it will then take the information from sensor e , 54 , having a field of view to measure the distance and angle to the next tree , and propel the machine forward . while propelling forward , sensor c , 56 determines when to stop by measuring the distance the machine has moved forward . this measurement is done by a pulse pick - up sensor c , 56 measuring the revolutions of tire 60 . the machine is moved forward automatically by the plc being operably engaged to the harvester engine to control the throttle of the engine , and stops when the measured distance has been traveled , as stated above . once again , the automatic cycle starts . shaker 22 is extended to grasp and shake the second tree . now sensor d , 52 , takes a new distance measurement to the next tree , as it extends shaker 22 . a calculation from the first tree to the second tree is made . the distance between the two is now used to figure the angular adjustment needed on the front steering caster . a signal actuates a valve to turn a steering caster on single forward wheel 26 , until sensor b , 58 , reaches the desired angle pointing shaker 22 in the right direction . forward movement begins to the recalculated position and the cycle of steps then repeats itself . with reference to the control system , the basic structure is described in u . s . pat . no . 6 , 658 , 834 using a programmable logic control device ( plc ). applicant hereby incorporates by reference , the entire u . s . pat . no . 6 , 658 , 834 . what is added to that system are the additional sensors and controls , providing the additional information needed , as described above , to now propel the machine automatically from tree to tree , putting it in the proper position for the shaker to grasp and shake each tree , rather than the operator driving the machine from tree to tree . the control system schematic diagram of fig4 , utilizes a control system 70 similar to the control system set forth in column 3 , line 39 through column 5 , line 15 , inclusive , of u . s . pat . no . 6 , 658 , 834 , which has been incorporated herein by reference , but with the additional sensors and controls set forth herein . the system includes programmable logic control device ( plc ) 74 with associated electronic and hydraulic systems to automatically control the tree sensing and shaking process . plc 74 receives input signals from tree sensor ( a ) 50 - 51 , shaker head position sensor ( d ) 52 , vision system sensor ( e ) 54 , pulse pick - up sensor ( c ) 56 and front steering sensor ( b ) 58 . plc 74 also receives input signals from the joystick 78 , engine control module 82 , which includes an rpm sensor , and engine speed and shaker duration monitor 86 . shaker head 22 is operated by shaker head clamping hydraulic cylinders 128 and shaker head motors 148 . predetermined programmable values , such as can be generated by potentiometer devices , as described in my prior patent , include a predetermined tree distance value potentiometer 94 , one or more predetermined engine rpm value potentiometers 98 , a predetermined clamping pressure value potentiometer 104 and a predetermined shaking time value potentiometer 112 , all of which are input into plc 74 . output control signals from plc 74 are provided to an engine rpm throttle servo 120 , described in my prior patent , part of engine control module 82 , one or more shaker head hydraulic fluid control valves 128 that supply hydraulic fluid to hydraulic cylinders 129 that control the inward and outward motion of the shaker head 22 , and a shaker head manifold having hydraulic control valves 140 that supply hydraulic fluid to shaker head clamping hydraulic cylinders 144 , and which provide electrical signals to one or more shaker head shaking motors 148 and hydraulic control valves 150 that supply hydraulic fluid to hydraulic cylinders 151 that control the direction of the front steering . it is to be understood that the present invention is not to be limited to the detailed features of any particular control system , such as that depicted in fig4 , such as other types of control systems that may use other types of input devices than potentiometers to provide predetermined values to the system . while the invention has been shown and described with reference to particular preferred embodiments , it will be understood by those skilled in the art that various alterations and modifications in form and detail may be made therein . accordingly , it is intended that the following claims cover all such alterations and modifications as may fall within the spirit and scope of the invention .
an automatically operated agricultural tree harvesting machine having systems for automatically steering , propelling and stopping the harvester machine to shake each tree , eliminating the need for the operator to steer or manually engage the shaker head . the system comprises a series of sensors to determine the location of each tree and a system for controlling the steering of the harvester and to determine the distance moved .