Abstract:
A control system utilizes operator satisfaction information for controlling an agricultural harvesting machine having adjustable crop processing structure. The control system includes actuators for controlling the crop processing structure and a controller connected to the actuators and to quality sensor structure. Information for at least one quality parameter of the harvesting process is entered on an operator input device, the entry being dependent on the level of satisfaction the operator perceives concerning the parameter, and the controller controls the actuators based on the operator satisfaction input. The controller stores information about the relationship between the output of the sensor and the satisfaction entry, and this relationship information is used for subsequent control purposes.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to agricultural implements such as combines and, more specifically, to control of adjustments on such implements. 
     BACKGROUND OF THE INVENTION 
     A modern agricultural harvester such as a combine is essentially a factory operating in the field with many interacting and complex adjustments to accommodate continually changing crop, field and machine conditions during harvest. These harvesters normally comprise a number of actuators for controlling process parameters to be set to appropriate operating positions or parameters. Generally, harvesters have controllers for automatic control of the actuators. 
     Solutions proposed in literature for an automatic machine adjustment have not been able to prove their value in practice. One reason for such inability is that the available sensors (as loss sensors, grain flow sensors, humidity sensors) have to be calibrated at harvest start under changing conditions. In addition, these sensors do not deliver sufficient information in order to adjust the complex system of harvesting speed, threshing cylinder rotations, concave gap, blower rotations and sieve adjustments. According to the respective harvesting conditions, the machine adjustment thus needs to be optimized for reaching the result desired by the operator in the best possible manner. The fine tuning of the machine requires much operator experience and finger tip feeling and is often very time consuming. Such tuning still has to be done by the operator. 
     Since the effect of different adjustments with respect to different quality criteria is often reciprocal, a number of compromises have to be made. For example, with “sharper threshing” for improving the threshing process, the amount of damaged grain and the straw destruction can increase. With larger sieve openings for reducing cleaning shoe losses, the purity in the grain tank can get worse. The operator can influence the total harvesting performance when he defines priorities for the different quality criteria according to economical requirements. 
     Examples of previous harvester controllers include those with look-up tables stored in an on-board memory, such as described in U.S. Pat. No. 6,205,384. With such systems, current conditions as a group are compared to groups stored in memory. When current conditions as a group match a stored group, the stored machine settings corresponding to the conditions are used to adjust the machine. New settings can be input by an operator via keyboard. One of the problems with this approach is basically that it is an open-loop approach. Machine settings are determined by historical data stored in the look-up table rather than by control results. As a result, such an open-loop type of system provides no compensation for changes in machine, crop, fields and environments. 
     Another example of harvester adjustment is shown and described in U.S. Pat. No. 5,586,033 wherein the controller trains a neural network model of the harvester with data. The model is then used to determine harvester settings. The controller comprises an operator interface allowing the operator to input the relative importance of a number of criteria, as grain loss, completeness of threshing, grain damage and dockage. According to the operator-defined relative importance of the criteria and to sensor inputs, the neural network determines the adjustment of the combine working parameters. This system suffers under the lack of sufficient and exact sensor data for getting feedback. Further, neural nets in large size require a prohibitive computational effort. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide an improved control system for an agricultural harvester. It is another object to provide such a system which overcomes most or all of the aforementioned problems. 
     The control system according to the invention comprises a controller arranged to control operating parameters of adjustable crop processing means of the harvesting machine, which could be a combine or any other harvesting machine, such as a forage harvester in which, for example, the gap between a chopping drum and a shear bar could be controlled. It is proposed that an operator interface device is provided receiving an operator feedback input regarding operator satisfaction with a quality parameter of the harvesting process. The controller uses the inputted information and controls the actuator accordingly. The inputted information can be used by the controller in combination with data from sensors. When different quality parameters are inputted, the operator can define a relative importance of these parameters or a target the operator would like to achieve, as low losses or high harvesting speed. The importance of the targets could also be pre-defined. The controller considers these inputs and controls the actuators accordingly. 
     Thus, the control system does not rely only on sensors for obtaining feedback information on the quality of the harvesting process, which are suffering under the described disadvantages such as necessity of calibration and insufficient number of data. It would even be possible to dispense with some or all of the sensors for obtaining feedback on the harvesting process. 
     For an initial setup, operating parameters of the actuators can be read from a memory, preferably according to actual crop characteristics and/or harvest conditions. The latter can be inputted by the operator into the operator interface device, or measured with appropriate sensors. After a certain harvesting time has elapsed, the operator can input information about his satisfaction with the obtained results via the operator interface device. The controller considers the operator input and uses known influences, trends and/or relationships between the quality parameters of the harvesting process and necessary alterations to the actuator operating parameters. The influence, impact or trend of alterations to the parameters upon the quality parameters is known in the art and used by the controller. This process can be repeated until the operator is entirely satisfied with all quality parameters of the harvesting process, or at least the most important quality parameters are accepted. 
     In a preferred embodiment, the control system of the harvesting machine comprises sensors capable of gaining information on at least one quality parameter of the harvesting process. Data from the sensors and the operator feedback data are stored together. They contain information about the sensor output data and the operator&#39;s satisfaction. For subsequent controlling purposes, the control system can, once a sufficient amount of data is stored, dispense with the operator feedback and rely on the sensor values, which are calibrated with the previously gained relationships. These relationships are preferably stored and recalled according to the respective crop characteristics and/or harvest conditions. 
     These and other objects, features and advantages of the invention will become apparent to one skilled in the art upon reading the following description in view of the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a harvester utilizing the control system of the present invention. 
     FIG. 2 is a schematic diagram of a first embodiment of a control system of the harvester shown in FIG.  1 . 
     FIG. 3 is a flow diagram indicating the operation of the control system of FIG.  2 . 
     FIG. 4 is a schematic diagram of a second embodiment of a control system of the harvester shown in FIG.  1 . 
     FIG. 5 is a flow diagram indicating the operation of the control system of FIG.  4 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, therein is shown an agricultural harvester in the form of a combine  100  comprising a main frame  112  having wheel structure  113  including front and rear ground engaging wheels  114  and  115  supporting the main frame for forward movement over a field of crop to be harvested. The front wheels  114  are driven by an electronically controlled hydrostatic transmission. 
     A vertically adjustable header or harvesting platform  116  is used for harvesting a crop and directing it to a feederhouse  118 . The feederhouse  118  is pivotally connected to the frame  112  and includes a conveyor for conveying the harvested crop to a beater  120 . The beater  120  directs the crop upwardly through an inlet transition section  122  to a rotary threshing and separating assembly  124 . Other orientations and types of threshing structures and other types of headers  116 , such as transverse frame supporting individual row units, could also be utilized. 
     The rotary threshing and separating assembly  124  threshes and separates the harvested crop material. Grain and chaff fall through a concave  125  and separation grates  123  on the bottom of the assembly  124  to a cleaning system  126 , and are cleaned by a chaffer  127  and a sieve  128  and air fan  129 . The cleaning system  126  removes the chaff and directs the clean grain to a clean grain tank by a grain auger  133 . The clean grain in the tank can be unloaded into a grain cart or truck by unloading auger  130 . Tailings fall into the return auger  131  and are conveyed to the rotor  37  where they are threshed a second time. 
     Threshed and separated straw is discharged from the rotary threshing and separating assembly  124  through an outlet  132  to a discharge beater  134 . The discharge beater  134  in turn propels the straw out the rear of the combine. It should be noted that the discharge beater  134  could also discharge crop material other than grain directly to a straw chopper. The operation of the combine is controlled from an operator&#39;s cab  135 . 
     The rotary threshing and separating assembly  124  comprises a cylindrical rotor housing  136  and a rotor  137  located inside the housing  136 . The front part of the rotor and the rotor housing define the infeed section  138 . Downstream from the infeed section  138  are the threshing section  139 , the separating section  140  and the discharge section  141 . The rotor  137  in the infeed section  138  is provided with a conical rotor drum having helical infeed elements for engaging harvested crop material received from the beater  120  and inlet transition section  122 . Immediately downstream from the infeed section  138  is the threshing section  139 . 
     In the threshing section  139  the rotor  137  comprises a cylindrical rotor drum having a number of threshing elements for threshing the harvested crop material received from the infeed section  138 . Downstream from the threshing section  139  is the separating section  140  wherein the grain trapped in the threshed crop material is released and falls to the cleaning system  128 . The separating section  140  merges into a discharge section  141  where crop material other than grain is expelled from the rotary threshing and separating assembly  124 . 
     An operator&#39;s console  150  located in the cab  135  includes conventional operator controls including a hydro shift lever  152  for manually controlling the speed range and output speed of the hydrostatic transmission  114 t. An operator interface device  154  in the cab  135  allows entry of information into a controller  155  comprising an on-board processor system, which provides automatic speed control and numerous other control functions described below for the harvester  100 . The operator can enter various types of information into the operator interface device  154 , including crop type, location, yield and the like. 
     Signals from the sensors include information on environmental variables such as relative humidity, and information on variables controlled by the on-board control system. Signals include vehicle speed signals from a radar sensor or other conventional ground speed transducer  160 , rotor and fan speed signals from transducers  162  and  164 , and concave clearance and chaffer and sieve opening signals from transducers  166 ,  168  and  170 , respectively. Additional signals originate from a grain loss sensor  172   a  at the exit of the rotary threshing and separating assembly  124  and left- and right-hand grain loss sensors  172   b  at the exit of the cleaning system  126 , a grain damage sensor  174  and various other sensor devices on the harvester. Signals from a tank cleanliness sensor  178   a , a mass flow sensor  178   b , a grain moisture sensor  178   c , a tailings volume sensor  178   d , and relative humidity, temperature and material moisture sensors  178   e ,  178   f  and  178   g  are also provided. 
     A bus directs signals from the mentioned sensors and an engine speed monitor, a grain mass flow monitor, and other microcontrollers on the harvester to the controller  155 . Signals from the operator interface  154  are also directed to the controller  155 . The controller  155  is connected to actuators  202 - 214  (FIG. 2) for controlling adjustable elements on the implement. Feedback signals from the actuators  202 - 214  are input to the controller  155 . 
     The actuators controlled by the controller  155  comprise an actuator  202  controlling the rotational speed of the rotary threshing and separating assembly  124 , an actuator  204  controlling the clearance of the concave  125 , an actuator  206  controlling the opening of a precleaner of the chaffer  127 , an actuator  208  controlling the opening width of the chaffer  127 , an actuator  210  controlling the opening of the sieve  128 , an actuator  212  controlling the speed of the air fan  129 , and an actuator  214  controlling the output speed of the hydrostatic transmission and thus the ground speed of the combine. These actuators are known in the art and thus only schematically indicated in FIG.  2 . 
     The first embodiment of the control system shown in FIG. 2 operates as schematically indicated in FIG.  3 . In a first block, indicated generally with  300 , an initial adjustment is performed. Block  300  comprises a number of steps  302 - 308 . At  302 , the operator by means of the operator interface device  154  inputs information about the actual crop characteristics, harvest conditions and the relative importance of a number of quality parameters. At  304 , recommended adjustments for the actuators  202 - 214  are read from a memory  156  of the controller  155 . It would also be possible to use input from the humidity, temperature and material moisture sensors  178   e ,  178   f  and  178   g  when they are in contact with the crop. At  306 , the actuators  202 - 214  are set into the read positions or operating parameters, whereby the controller  155  may use feedback from the feedback transducers  160 ,  162 ,  164 ,  166 ,  168  and  170  of the actuators  202 - 214 . Then, the combine  100  harvests a part of the field at  308 . The combine speed is controlled by the controller  155 , but can be manually influenced by the operator by means of the hydro shift lever  152 . 
     An operator supported optimization block generally indicated with  310  follows the initial adjustment block  300 . After a delay in step  312  for obtaining time for a stabilization of the process, the operator can input in step  314  whether he is satisfied with the result of the harvesting process. The delay time can be predefined, or it can end when the operator gives an appropriate input into the operator interface device  154  when according to his opinion a sufficient harvesting time has lapsed. In step  314 , the operator inputs into the operator interface device  154 , whether a number of quality parameters of the harvesting process are too high, acceptable, or too low. In another embodiment, the operator could simply input whether the quality parameters are considered as acceptable or not. These quality parameters are in this embodiment the grain loss of the rotary threshing and separating assembly  124 , the grain loss of the cleaning system  126 , the threshing quality of the threshing section  139 , the grain damage and the dockage of the material in the clean grain tank. The operator may have to stop the combine  10 , leave the operator&#39;s cab  135  and check the respective parameters visually and/or by means of suited instruments as containers for collecting lost grain. When in step  314 , any of the quality parameters of the harvesting process is not acceptable, step  316  is performed, in which the controller  155  adjusts the actuators  202 - 214  according to known impacts, influences or relationships or trends between the acceptability of the operating parameters and the position or operating parameters of the actuators. These relationships are incorporated in programs running in the controller. The controller  155  makes use of the fact that the trend of the effects caused by adjusting a functional element of the combine  100  is known. The controller  155  is an intelligent system taking over the methods according to which an experienced operator would proceed during adjusting the combine  10 . For performing this task, the controller  155  may incorporate functions of a fuzzy controller as described in U.S. Pat. No. 6,315,658 or a neuronal network as disclosed in U.S. Pat. No. 5,586,033 the disclosure of both references being incorporated herein by reference. Thus, when for example the cleaner loss is considered as too high, the controller  155  will open the precleaner, the chaffer  127  and the sieve  128 . All or a number of the remaining actuators  208 - 214  may have to be adjusted, as well. Step  316  is followed again by step  312 . The controller  155  hence brings the actuators  208 - 214  in cooperation with the operator in an iterative manner into positions or operating parameters yielding a desired quality of the harvesting process. Thereby, the inputted relative importance of the parameters is considered. 
     When step  314  reveals that all quality parameters of the harvesting process are acceptable, step  318  is performed, in which harvesting is continued. Step  320  can be executed by an appropriate input into the operator interface device  154 . Then, in step  322  the actual operating parameters of the actuators  208 - 214  are stored in memory  156  together with information about the inputted and/or measured harvesting conditions and the relative importance of the parameters. The operating parameters will be recalled in subsequent executions of step  304 . 
     It should be noted that the first embodiment of the invention shown in FIGS. 2 and 3 does not make use of the grain loss sensors  172   a ,  172   b , the grain damage sensor  174 , the tank cleanliness sensor  178   a , the mass flow sensor  178   b , the grain moisture sensor  178   c  and the tailings volume sensor  178   d . Thus, calibration problems of the sensors are avoided, and it would even be possible to dispense with the sensors. 
     On the other hand, the second embodiment of the controller  155  shown in FIG. 4 uses the outputs of the various sensors. In the second embodiment, comparable elements have the same reference numerals as those of the first embodiment. The controller  155  is connected to the grain loss sensors  172   a ,  172   b , the grain damage sensor  174 , the tank cleanliness sensor  178   a , the mass flow sensor  178   b  and the grain moisture sensor  178   c . It would also be possible to provide signals from at least one of a sensor sensing the straw humidity, a sensor sensing the throughput rate of the combine  100  by measuring the drive torque of the rotary threshing and separating assembly  124  or the thickness of the crop mat in the feederhouse  118 , and a sensor sensing the part of the grain separated in the threshing section  139 . As in the first embodiment, the operator can input via the operator interface device  154  whether he considers quality parameters of the harvesting process as too high, too low or acceptable. In another embodiment, he just has the choice between acceptable and not acceptable parameters. A switch  157  allows the operator to switch between an automatic mode and a manual mode, in which the sensor signals are not considered and the controller works only based upon the operator inputs. 
     The operation of the control system according to the second embodiment is represented in FIG.  5 . The first block  300 , the initial adjustment, is identical with block  300  in FIG.  3 . The actuators  202 - 214  of the combine are thus set in sub-steps  302 - 308  to positions or operating parameters read from memory  156  according to inputted and/or measured conditions. Additionally, the relative importance of the parameters is inputted. The second block is also generally indicated as  310 , since it is identical with the operator supported optimization process block  310  in FIG.  3 . The operator thus checks whether the quality parameters of the harvesting process are acceptable or too high or too low (respectively acceptable or not), and makes corresponding inputs to the operator interface device  154 . The controller  155  adjusts the actuators  202 - 214  as described above, using known relationships or trends between the quality parameters and the actuator values. When the operator is content with all quality parameters, step  317  follows step  314 . At  317 , an information about the values provided by the sensors  172   a ,  172   b ,  174  and  178   a - 178   d  is stored in memory  156 , preferably together with the information on the actual crop characteristics and harvest conditions inputted and/or measured in step  302 . In the disclosed embodiment, the fact that the sensor values are stored is already indicating that the operator is satisfied with the quality parameters, since otherwise step  317  would not be reached. The memory  156  is hence provided with information about the sensor outputs, knowing that the operator has accepted the quality parameters. Consequently, information that can be considered as calibration information of the sensors is obtained and stored. It should be noted that step  317  can also be performed before or after step  316 , thus during the optimization process. Then, operator inputs into the operator interface device regarding the acceptance of the quality parameters of the harvesting process would be stored together with the sensor values. Steps  318 - 322 , as in FIG. 3, follow step  317 . 
     The advantage of the calibration step  317  is that calibration information regarding the sensors  172   a ,  172   b ,  174  and  178   a - 178   d  is available. This can be used for future harvesting tasks as indicated by the dotted lines and step  323  in FIG. 5, in which block  310  is omitted and the actuators  202 - 214  are controlled by the controller based on the sensor outputs using the calibration information. The information about the actual crop characteristics and harvest conditions and the crop characteristics and harvest conditions at the time the calibration information was obtained, is considered, as well, as the relative importance of the parameters. When the operator should notice that the quality parameters are not acceptable in the automatic mode, he can initiate another execution of block  310  by an appropriate input into the operator interface device  154 . 
     Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims. Although the harvester is shown as a combine, the system described above is also suitable for use with other harvesters as well as other implements having interacting and complex adjustments to accommodate various types of continually changing operating conditions. The system described is particularly adaptable, for example, to many agricultural and construction implements wherein sensor and feedback information is relatively imprecise.