Patent Publication Number: US-2016237650-A1

Title: Engine control system

Description:
TECHNICAL FIELD 
     The present disclosure relates to an engine control system of a machine. More particularly, the present disclosure relates to the engine control system based on soil parameters of a payload associated with the machine. 
     BACKGROUND 
     Machines such as, for example, wheel loaders, track type tractors, and other types of heavy machinery may be utilized for a variety of tasks. These machines include a power source, which may be, for example, an engine, such as a diesel engine, a gasoline engine, or a natural gas engine that provides power required to complete such tasks. Such power is directed to various tools, implements, and other components of the machine to assist in performing these tasks. 
     In some situations based on a moisture content of soil, engine power required to operate the machine and perform the desired tasks may vary. In one example, relatively more engine power may be required to operate the machine when the moisture content of the soil is optimized based on soil type and therefore maximum density. In another example, for soils having less optimized moisture content and therefore lower density, lesser engine power may be required to perform the tasks. Generally, an operator of the machine may manually control an operation of the engine based on engine lug and/or feel. However, this may not be a very efficient way of handling and operating the machine since reliance on manual operation may be high in this situation. 
     U.S. Patent Published Application Number 2014/0255095 describes a method for construction of earthen fills that comprises use of actual, cumulative field compaction energy generated by soil compactors as a function of rolling resistance with soil densification, to determine the asymptotic energy-density approach range. 
     In known systems that do not consider soil parameters while operating, the machine sometimes uses excessive power to move material. This use of excessive engine power can increase fuel consumption, increase fuel refill frequency and result in increased operating costs. Hence there is a need for an improved automated system and method for controlling engine operation. 
     SUMMARY OF THE DISCLOSURE 
     In an aspect of the present disclosure, an engine control system is provided. The engine control system includes a moisture content sensor associated with an implement of a machine. The moisture content sensor is configured to generate a signal indicative of a moisture content of soil. The engine control system also includes a control module coupled to the moisture content sensor. The control module is configured to receive the signal indicative of the moisture content of the soil. The control module is configured to receive a signal indicative of mass readings associated with the soil. The control module is configured to correlate the moisture content and the mass readings associated with the soil based on a type of the soil. The control module is configured to control at least one of a power and a speed setting associated with an engine of the machine based, at least in part, on the correlation. 
     Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of an exemplary machine, according to one embodiment of the present disclosure; 
         FIG. 2  is a block diagram of an engine control system associated with the machine of  FIG. 1 , according to one embodiment of the present disclosure; and 
         FIG. 3  is a flowchart illustrating a method of operation of the engine control system, according to one embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Referring to  FIG. 1 , an exemplary machine  10  is illustrated. More specifically, the machine  10  is an excavator. The machine  10  is configured to perform various tasks such as excavation, demolishment, material handling, and so on. In other embodiments, the machine  10  may be any other machine such as a wheel loader, a dozer, a track type tractor, a truck, and so on. The machine  10  may be any machine related to an industry such as construction, agriculture, transportation, forestry, material handling, waste management, and so on. 
     The machine  10  includes a frame  12 . The frame  12  is configured to support various components of the machine  10  thereon. The machine  10  includes an engine  14  mounted on the frame  12 . The engine  14  may be any internal combustion engine powered by a fuel such as diesel, gasoline, natural gas, and so on or a combination thereof. The engine  14  is configured to provide motive power to the machine  10 . 
     The machine  10  includes an operator cabin  16  mounted on the frame  12 . The operator cabin  16  is configured to house various controls of the machine  10  including, but not limited to, a steering, levers, pedals, joysticks, buttons, an operator interface, audio video devices, and an operator seat. The controls are configured to operate and control the machine  10  on the ground. The machine  10  also includes tracks  18  mounted to the frame  12 . The tracks  18  are configured to support and provide mobility to the machine  10  on the ground. 
     The machine  10  includes a linkage assembly  20 . The linkage assembly  20  includes a boom  22  movably coupled to the frame  12 . The linkage assembly  20  also includes a stick  24  movably coupled to the boom  22 . The linkage assembly  20  further includes an implement, such as a bucket  26 , movably coupled to the stick  24 . In other embodiments, the linkage assembly  20  may include any other implement such as, a blade, an auger, a hammer, and so on based on application requirements. The linkage assembly  20  also includes one or more hydraulic cylinders  28  configured to provide movement to the boom  22 , the stick  24 , and/or the bucket  26 . 
     The linkage assembly  20  is configured to perform activities such as excavation, demolishment, transportation, material handling, and so on based on application requirements. Additionally, the machine  10  may include other components and systems such as, an engine control system  30  (see  FIG. 2 ), a transmission system (not shown), a drive control system (not shown), a safety system (not shown), and so on without limiting the scope of the disclosure. 
     Referring to  FIG. 2 , a schematic representation of the engine control system  30  is illustrated. The engine control system  30  includes a moisture content sensor  32  associated with the implement of the machine  10 . More specifically, the moisture content sensor  32  is coupled to the bucket  26  of the machine  10  in a manner such that the moisture content sensor  32  is in contact with material such as soil being moved by the bucket  26 . 
     In one embodiment, the moisture content sensor  32  may be coupled to an inner surface  34  of the bucket  26 . In another embodiment, the moisture content sensor  32  may be coupled to an outer surface  36  of the bucket  26 . In yet another embodiment, the moisture content sensor  32  may be coupled to any other component of the machine  10  such as the boom  22 , the stick  24 , the track  18 , the frame  12 , and so on based on application requirements. The moisture content sensor  32  is configured to generate a signal indicative of a moisture content of the soil. 
     The engine control system  30  also includes a control module  38  coupled to the moisture content sensor  32 . The control module  38  is configured to receive the signal indicative of the moisture content of the soil from the moisture content sensor  32 . The control module  38  is also configured to receive a signal indicative of mass readings associated with the soil present in the bucket  26 . In one embodiment, the mass readings of the soil may be received from one or more pressure sensors (not shown) associated with the bucket  26  and/or the hydraulic cylinders  28 . In another embodiment, the mass readings of the soil may be received based on a movement of the linkage assembly  20  or the frame  12 . 
     In another embodiment, the mass readings of the soil may be received based on hydraulic power generated by a hydraulic system (not shown) of the machine  10  and/or hydraulic power required by the hydraulic cylinders  28 , and so on. In yet another embodiment, the mass readings of the soil may be received from a payload control system (not shown), a production measurement system (not shown), and so on of the machine  10 . It should be noted that the mass readings of the soil present within the bucket  26  described herein is merely exemplary and may be determined by any method  42  known in the art without limiting the scope of the disclosure. The moisture content and the mass readings of the soil are received by the control module  38  on a per bucket basis. 
     Further, the control module  38  is also configured to receive a signal indicative of a type of the soil. For example, the type of soil may vary such as sandy, clay, rocky, and so on based on a geographic location of a worksite. More specifically, in one embodiment, the control module  38  may receive the signal indicative of the type of soil based on a location signal of the machine  10 . The location signal of the machine  10  may be received from a positioning system (not shown) of the machine  10  coupled to the control module  38  such as a Global Positioning System (GPS), an Inertial Navigation System (INS), and so on. In such an embodiment, the control module  38  may be coupled to a database  40 . The data related to the type of the soil may be retrieved from the database  40  based on a current location of the machine  10 . 
     In another embodiment, the control module  38  may receive the signal indicative of the type of the soil based on a location map stored in the database  40 . The location map may include the type of the soil for different locations. In another embodiment, the signal indicative of the type of the soil may be based on a site of the machine  10 . In such an embodiment, the database  40  may include a dataset having the type of the soil for different sites. In yet another embodiment, the type of the soil may be manually fed to the control module  38  via the operator interface. 
     Further, the control module  38  is configured to determine a volume of the soil present in the bucket  26  based on the type of the soil, the mass readings of the soil and the moisture content of the soil. Accordingly, the control module  38  is configured to provide a notification of a current volume of the soil dug by the machine  10 . This notification of the volume of the soil dug by the machine  10  may be provided to the operator via a suitable text or audio message, based on the requirement. In one example, a display notification may be provided to the operator seated within the operator cabin  16  of the machine  10  via a display panel. 
     In one embodiment, the volume of the soil present in the bucket  26  may be equivalent to a volume of the bucket  26  when the bucket  26  is fully filled with the soil. The control module  38  may determine the volume of the bucket  26  based on bucket specifications stored in the database  40  such as a type of the bucket  26 , a part number of the bucket  26 , dimensions of the bucket  26 , a machine status/configuration, and so on. In another embodiment, the volume of the bucket  26  may be manually fed to the control module  38  through the operator interface. 
     In another embodiment, the control module  38  may be configured to determine the volume of the soil in the bucket  26  based on a cohesion estimate of the soil. The cohesion estimate may be determined based on a correlation stored in the database  40 . The correlation may include a mathematical expression between the moisture content of the soil, the type of the soil, and the mass readings of the soil in the bucket  26 . In another embodiment, the control module  38  may receive the cohesion estimate from the database  40 . The database  40  may include a dataset having values of the cohesion estimate for varying values of the moisture content of the soil, the type of the soil, and the mass readings of the soil in the bucket  26 . 
     In some embodiments, the control module  38  may be configured to control the hydraulic cylinders  28  associated with the bucket  26  based on the cohesion estimate of the soil. More specifically, based on the moisture content of the soil, the type of the soil, the mass readings of the soil, and the cohesion estimate of the soil, the control module  38  is configured to determine a fill factor of the bucket  26 . The fill factor of the bucket  26  is indicative of a quantity of the soil present in the bucket  26  in order to determine loading levels such as overloading, under loading, optimum loading, and so on of the bucket  26 . Based on the fill factor, the control module  38  is configured to control the hydraulic cylinders  28  in order to optimize a dig effort of the bucket  26  and/or to optimize the loading level of the bucket  26 . 
     Based on the mass readings and the determined volume of the soil in the bucket  26  for a given cycle, the control module  38  is configured to determine a density or a dry density of the soil. Further, the control module  38  is configured to determine a soil zone on a proctor curve stored in the database  40  for the given type of the soil. The proctor curve is a graphical representation of soil conditions based on a dry density and a moisture content of the soil, for the given type of the soil. The soil zone is a relative segment of the proctor curve that determines soil conditions such as loosely packed, tightly packed, optimum moisture, maximum dry density and so on. According to the type of the soil, the control module  38  may select a relevant proctor curve. Further, based on the density and the moisture content of the soil, the control module  38  is configured to determine the soil zone on the relevant proctor curve. The control module  38  may determine the soil zone based on a dataset stored in the database  40 . The dataset may include various soil zones based on varying values of the density and the moisture content of the soil. In another embodiment, the database  40  may include a correlation such as a mathematical expression between the soil zone, the density, and the moisture content of the soil for the given type of the soil. 
     Based on the determined soil zone, the control module  38  is configured to control at least one engine parameter associated with the engine  14  of the machine  10  based, at least in part, on the correlation. The engine parameter may include a power of the engine  14 , a speed setting of the engine  14 , and so on. For example, when the control module  38  determines a dense, or optimized proctor curve load, the control module  38  may be configured to increase the power and/or the speed setting of the engine  14  so that the engine  14  operates at a higher power or speed setting. Similarly, when the control module  38  determines a less dense or less optimized proctor curve load, the control module  38  may be configured to reduce the power and/or the speed setting of the engine  14  so that the engine  14  operates at a lower power or speed setting. 
     In one embodiment, based on the type of the soil, the mass readings of the soil, and the moisture content of the soil, the control module  38  may utilize the determined cohesion estimate of the soil to control an operation of the hydraulic cylinders  28  associated with the linkage assembly  20 . For example, based on the cohesion estimate of the soil, the control module  38  determines if the linkage assembly  20  of the machine  10  needs to be operated more aggressively or less aggressively and accordingly sends control signals to actuate the hydraulic cylinders  28  associated with the bucket  26 . 
     Additionally, the control module  38  is configured to estimate a fuel refill schedule of the machine  10 . Based on the moisture content of the soil, the type of the soil, the mass readings of the soil, and bucket usage data, the control module  38  is configured to determine bucket load data per work cycle. The control module  38  is configured to receive fuel rate data indicative of rate of fuel consumption in the system from an engine control module (not shown) coupled to the control module  38 . Based on the type of the soil, the moisture content of the soil, and the mass readings of the soil, the control module  38  is configured to combine the fuel rate data with the data associated with the soil to predict a fuel usage of the engine  14  required for completing the designated task. Further, based on a known fuel tank capacity of the fuel tank of the machine  10  and the predicted fuel usage, the control module  38  may determine a fuel refill schedule of the machine  10 . The fuel refill schedule may include fuel consumption per work cycle, time for next refuel, and so on. 
     In situations when the moisture content of the soil, the type of the soil, and/or the mass readings of the soil may change, the dig effort of the bucket  26  may change accordingly resulting in change of fuel usage and engine working conditions. For example, if the moisture content of the soil over multiple bucket cycles remains approximately constant, the control module  38  may predict that the fuel usage may not differ significantly over time. In another example, if the moisture content of the soil either increases or decreases over multiple bucket cycles, the control module  38  may predict that the fuel usage may correspondingly vary. Accordingly, based on the predicted fuel usage and engine usage parameters, the control module  38  may predict the fuel refill schedule of the machine  10 . During high fuel usage, time required for the fuel tank to empty may be less, leading to increased fuel refill cycles. Similarly, during low fuel usage, the time required for the fuel tank to empty may be more, leading to reduced fuel refill cycles. 
     INDUSTRIAL APPLICABILITY 
     The present disclosure relates to a method  42  of controlling the engine  14  of the machine  10  by the control module  38 . Referring to  FIG. 3 , a flowchart of the method  42  is illustrated. At step  44 , the control module  38  receives the signal indicative of the moisture content of the soil from the moisture content sensor  32 . At step  46 , the control module  38  receives the signal indicative of the mass readings associated with the soil. The mass readings of the soil may be received from the pressure sensors associated with the bucket  26  and/or the hydraulic cylinders  28 , based on the movement of the linkage assembly  20 , based on the hydraulic power generated by the hydraulic system of the machine  10  and/or the hydraulic power required by the hydraulic cylinders  28 , the payload control system, the production measurement system, and so on. 
     At step  48 , the control module  38  correlates the moisture content and the mass readings associated with the soil for the given type of the soil. The type of the soil may be received based on the location signal of the machine  10 , the location map stored in the database  40 , a site data, and so on. At step  50 , based on the correlation, the control module  38  is configured to control at least one of the power and the speed setting associated with the engine  14  of the machine  10 . The control module  38  is configured to control the engine parameter in order to optimize the engine working conditions for each work cycle. 
     The control module  38  provides an effective and a cost efficient method  42  to optimize the engine working conditions for different soil types and work cycles. For example, the control module  38  may reduce the engine parameters in situations when the type of soil may not require a more aggressive digging style. Also, the control module  38  may increase the engine parameters in situations when the type of soil may require a more aggressive digging style. It should be noted that the control module  38  may be overridden by operator commands and vice versa based on application requirements. 
     Also, the control module  38  may determine the volume of the soil present in the bucket  26  based on the bucket specifications without use of additional systems. Additionally, the control module  38  may estimate the fuel refill schedule for the machine  10  based on the moisture content of the soil, the type of the soil, the mass readings of the soil, and the bucket usage data without use of additional systems. As a result, the control module  38  in turn improves machine efficiency, improves fuel efficiency, improves component life, reduces machine abuse, reduces operator dependency, and so on. 
     While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of the disclosure. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.