Abstract:
A movable machine including a chassis, a tool coupled to the chassis, an operator control carried by the chassis and a controller. The controller is communicatively coupled to the operator control. The controller being configured to send a force feedback and/or a vibration feedback to the operator control thereby conveying information to the operator. The information is not related to a load encountered by the tool.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is the National Stage of International Application No. PCT/US2015/042790 filed Jul. 30, 2015, which claims priority to U.S. Provisional Patent Application No. 62/031,207 filed Jul. 31, 2014, the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to vehicular controls and more specifically to a feedback regime for a vehicular control. 
         [0004]    2. Description of the Related Art 
         [0005]    Vehicles such as skid steer loaders are a mainstay of agricultural and construction work. In their most common configuration, they have two drive wheels on each side of a chassis that are driven in rotation by one or more hydraulic motors coupled to the wheels on one side and another one or more hydraulic motors coupled to the wheels on the other side. 
         [0006]    The wheels on one side of the vehicle can be driven independently of the wheels on the other side of the vehicle. This permits the wheels on opposing sides of the vehicle to be rotated at different speeds, in opposite directions, or both. By rotating in opposite directions, the skid steer can rotate in place about a vertical axis that extends through the vehicle itself. 
         [0007]    The vehicles often have an overall size of about 4×8′ to 7×12′ feet which, when combined with their ability to rotate in place, gives them considerable mobility at a worksite. This mobility makes them a preferred vehicle. 
         [0008]    Skid steer vehicles have at least one loader lift arm that is pivotally coupled to the chassis of the vehicle to raise and lower at the operator&#39;s command. This arm typically has a bucket, blade, or other implement attached to the end of the arm that is lifted and lowered thereby. Perhaps most commonly, a bucket is attached to the arm and the skid steer vehicle. This bucket is commonly used to carry supplies or particulate matter such as gravel, sand, or dirt around a worksite. 
         [0009]    Joysticks are well known and widely employed for operator input of vehicles including skid steer loaders. Joysticks are frequently used on vehicles having significant hydraulic operational components, such as hydraulically powered drive means, steering means, and work implements e.g., buckets in the case of front-end loaders, or booms in the case of excavators and back-hoes. 
         [0010]    The operating position for joystick controlled vehicles typically provides for an operator to be in a sitting position. Armrests are often provided for the operator with the joysticks conveniently located proximate to the armrest for reducing operator fatigue. Reduced fatigue may, in turn, advance worker safety for both the vehicle operator, and others working in the vicinity of the vehicle. The joysticks allow operators of agricultural and construction equipment to control various vehicle and/or implement functions. 
         [0011]    In the past, force feedback systems of a control related to a load encountered by a load bucket or blade of a vehicle, which was undertaken to give the operator a feel for the load that is being applied to the implement. Such a device is detailed in U.S. Pat. No. 4,800,721. 
         [0012]    A problem with the monolithic approach of the past is that other information has to be conveyed by way of another system or display rather than the operator control. 
         [0013]    What is needed in the art is a control method to convey a multitude of information to an operator of a control device by way of that control device. 
       SUMMARY OF THE INVENTION 
       [0014]    The invention seeks to provide a feedback control system and method that will expand the utility of the control in a simplified, economical and easy to understand way. 
         [0015]    In one form, the invention is directed to a movable machine including a chassis, a tool coupled to the chassis, an operator control carried by the chassis and a controller. The controller is communicatively coupled to the operator control. The controller is configured to send a force and/or vibration feedback to the operator control thereby conveying information to the operator. The information is not related to a load encountered by the tool. 
         [0016]    In another form, the invention is a force and/or vibration feedback method for an operator control of a movable machine, the machine having a chassis, a tool coupled to the chassis, and the operator control carried by the chassis. The method includes the step of sending a force and/or vibration feedback to the operator control thereby conveying information to the operator. The information is not related to a load encountered by the tool. 
         [0017]    An advantage of the present invention is that information is efficiently passed on to the machine operator by way of the control grasped by the operator. 
         [0018]    Another advantage of the present invention is that in a noisy environment an alert can be quickly brought to the attention of the operator. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0020]      FIG. 1  is a side view of a vehicle in the form of a skid steer loader having a control system embodying the present invention; 
           [0021]      FIG. 2  is a schematical view of the vehicle of  FIG. 1  having a joystick control of the present invention; 
           [0022]      FIG. 3  is a flowchart illustrating a force/vibration feedback regime of one embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0023]      FIG. 4  is a flowchart illustrating a force feedback regime of another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0024]      FIG. 5  is a flowchart illustrating a vibration feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0025]      FIG. 6  is a flowchart illustrating yet another force feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0026]      FIG. 7  is a flowchart illustrating yet another force feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0027]      FIG. 8  is a flowchart illustrating yet another force feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0028]      FIG. 9  is a flowchart illustrating yet another force/vibration feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0029]      FIG. 10  is a flowchart illustrating yet another force/vibration feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0030]      FIG. 11  is a flowchart illustrating yet another force feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0031]      FIG. 12  is a flowchart illustrating yet another force/vibration feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 ; 
           [0032]      FIG. 13  is a functional block diagram illustrating components and functions of the control system of  FIGS. 1 and 2 ; and 
           [0033]      FIG. 14  is a flowchart illustrating yet another force/vibration feedback regime of yet another embodiment of the present invention used by the control system of  FIGS. 1 and 2 . 
       
    
    
       [0034]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0035]    Referring now to the drawings, and more particularly to  FIGS. 1 and 2  there is shown a movable machine  10  in the form of a vehicle  10  and more particularly in the form of a skid steer loader  10 . The present invention is applicable to any vehicle and particularly to vehicles using controls that do not inherently have a reaction force directed back to the control that relates to a task undertaken by an operator of machine  10 . Machine  10  includes a frame or chassis  12 , a set of ground engaging devices, here illustrated as wheels  14 , and a tool  16 , here shown as a bucket  16 . A control system  18  interfaces with parts of machine  10  that are not illustrated such as a transmission, an engine and other control systems. Control system  18  includes a controller  20 , an operator control  22 , sensors  24  and actuators  26 . Controller  20  may be a stand-alone controller that communicates with other controllers used in machine  10 , or the functions of controller  20  may be incorporated in another controller that performs other functions, such as an engine control unit (ECU) of machine  10 . 
         [0036]    Operator control  22  may be in the form of a joystick  22  having feedback actuators, which may be electrical motors, hydraulic actuators, pneumatic actuators or the like. For purposes of discussion, electrical actuators will be considered as providing a force feedback to joystick  22 . While joystick  22  is discussed in the singular, it is understood that machine  10  may have more than one joystick  22  for controlling different aspects of machine  10  and the exemplification carried out on the two or more joysticks may be similar or different and that the force feedback may be coordinated between multiple joysticks. Controller  20  receives controlling information from joystick  22  as the operator moves joystick  22 , and controller  20  sends feedback to joystick  22  to thereby enhance the experience of the operator, or to alert the operator to a new condition of machine  10 , or the environment around machine  10 , or a communication to the operator from a device other than machine  10 . 
         [0037]    Now, additionally referring to  FIG. 3 , there is illustrated a method  100 , where at step  102  controller  20  determines whether machine  10  is approaching a maximum productivity and if so then at step  104  the force feedback, at least in the direction joystick  22  is being moved, has an increased stiffness or a vibration applied to joystick  22  to alert the operator of the condition. It is to be understood that the when the words “vibration” or “shaking” are used it can mean a buzzing sensation that is modulated, a fixed frequency vibration, a variable frequency vibration, of a singular or multiple amplitudes. The operator will experience the sensation in the feel of joystick  22 , but that movement is such that it is either not picked up by the position sensors of joystick  22  or is eliminated by controller  20  so that such a movement is not translated into a movement of the element of machine  10  that is being controlled by joystick  22 . 
         [0038]    Now, additionally referring to  FIG. 4 , there is illustrated a method  200 , where at step  202  it is determined whether the speed of machine  10  is beyond a predetermined amount, and if so at step  204  the axis in which joystick  22  is being moved for steering is stiffened by increasing the force feedback (based on a calculation from element  210 ) to thereby ensure that a steering motion is not too extreme. Then at step  206  once the speed is reduced then the force feedback in that axis is reduced to a normal force feedback, which may be reduced to zero. If the speed is still high then the steering force is again reevaluated at step  204 . This method may be carried out in a gradual manner, for example, as a forward speed is increased the stiffness is increased proportionately. Conversely, as the speed is decreased then the stiffness is proportionately decreased. 
         [0039]    Now, additionally referring to  FIG. 5 , there is shown a method  300 , where at step  302  it is determined if machine  10  is enabled. For purposes of this example two joysticks are assumed, one controlling the direction and power applied to wheels  14 , and one for the operation of bucket  16 . The right side of method  300 , having elements  304 ,  306  and  308 , where, as the load in bucket  16  changes, vibration feedback applied to one joystick is related to the load in bucket  16 . On the left side of method  300 , having elements  310 ,  312  and  314 , is illustrated the movement of machine  10  as it is, for example, driven so that bucket  16  encounters a load on the ground, with an accompanying vibration feedback provided to the joystick controlling the movement of machine  10  and relating to the force encountered by wheels  12  as they push into a load. 
         [0040]    Now, additionally referring to  FIG. 6 , there is shown a method  400 , where at step  402  it is determined if the terrain is rough, such as a predetermined amount of bounce is being experienced by machine  10 . If so, then at step  404  the stiffness of movement of joystick  22  is increased by an increase in the force feedback applied thereto. Once it is determined (at step  406 ) that the terrain is no longer too rough, then at step  408  the stiffness of movement of joystick  22  is reduced. This helps to preclude unintended movement of joystick  22  when machine  10  is encountering unusually uneven ground. 
         [0041]    Now, additionally referring to  FIG. 7 , there is shown a method  500 , where at step  502  it is determined whether the bucket shake selection is active and bucket  16  is being emptied. If so, then the force feedback to joystick  22  is reduced at step  504  to allow the operator to easily shake bucket  16  to knock loose any material therein. Then if the bucket is not being emptied hence bucket shake is no longer active, as determined at step  506 , then the force feedback is returned to a normal or previous level at step  508 . 
         [0042]    Now, additionally referring to  FIG. 8 , there is shown a method  600 , where at step  602  it is determined if the hydraulic system of vehicle  10  is enabled, if not then at step  604  the force feedback to joystick  22  is increased to lock joystick  22  from being moved. Alternatively, a neutral lock can be applied to joystick  22 . Once the hydraulic system is enabled, as detected at step  606 , then any extra force or neutral lock is removed at step  608  from joystick  22 . 
         [0043]    Now, additionally referring to  FIG. 9 , there is shown a method  700 , where at step  702  controller  20  is alerted to an active fault code, then at step  704  that information is conveyed to the operator by a change in the force feedback and/or by using a vibration of joystick  22 . This may result in the operator then being made aware of an element now being displayed on a display (not illustrated). The continuation of a serious fault continues to alert the operator until the fault is cleared (step  706 ), or after a predetermined amount of time. It is contemplated that a vibration of joystick  22  may be in an axis, which is not currently being activated, or even in an unused axis. For example, if joystick  22  only operates in an X-Y plane, then the vibration may be in the Z direction. 
         [0044]    Now, additionally referring to  FIG. 10 , there is shown a method  800 , which is again perhaps a two joystick situation, where at steps  802  and  804  it is determined respectively if the loader arm and the bucket are close to target positions and if so then the particular joystick has a change in the force feedback and/or a vibration applied (steps  806  and  808 ) to alert the operator that a target has been approached. The illustration shows inputs from elements  810 ,  812 ,  814  and  816  respectively, which may include information from sensors  24 . The magnitude of the force and/or vibration feedback is based on the velocity and/or distance from the target position. 
         [0045]    Now, additionally referring to  FIG. 11 , there is shown a selection method  900 , where at elements  902 ,  904  and  906  it is determined if the operator is selecting an aggressive setting ( 902 ), a smooth setting ( 906 ) or in between, a mid setting ( 904 ). As a result of the selection then the application of the force feedback, of the other methods discussed herein, are respectively selected to thereby correspond with the selected element  908 ,  910  or  912 . 
         [0046]    Now, additionally referring to  FIG. 12 , there is shown a method  1000 , where at step  1002  it is determined if the operator is receiving a notification. If so, then joystick  22  has the force feedback changed or a vibration is caused in joystick  22  at step  1004 . The notification may be the operator&#39;s cell phone (by way of a Bluetooth® connection) or a radio squelch being broken and conveyed to controller  20 . There may be a cell phone interface in the form of a Bluetooth Connectivity module that sends an alert to controller  20  when the operator&#39;s cell phone rings, which in turn causes the joystick vibration actuator to vibrate joystick  22  to thereby alert the operator to answer a phone call. Other forms of communication are also contemplated that may result in a similar alert to the operator. If more than one form of communication signal is sent to controller  20  the vibration sent to joystick  22  can be selected to have a unique vibration sensation to correspond with the specific communication signal. For example, one form could be an intermittent vibration, and another a constant vibration. 
         [0047]    Now, additionally referring to  FIG. 13  there is shown functional elements of an embodiment of the present invention that may exist in control system  18 . Sensors  24  may be in the form of proximity sensors (back, left and right), sensors reporting the states of vehicle  10 , and/or ground terrain sensors, all of which provide information to controller  20 . Also illustrated is the connectivity of a cell phone. Actuators  26  provide motion to the drives of machine  10  upon the command from joystick  22 . The X-axis and Y-axis force actuators are also depicted as part of joystick  22 . The vibration actuator of joystick  22  is also illustrated. It is shown that the force feedback can be effected individually by the X, Y or vibration actuators or in a coordinated manner, and that they can be related either to the ground drive or the loader. 
         [0048]    Now, additionally referring to  FIG. 14  there is shown a flowchart illustrating the functioning of an embodiment of the present invention in the form of a method  1100 . At steps  1102 ,  1104  and  1106 , the respective sensors  24  detect an object that is less than a predetermined distance (X, Y-left or Y-right) from machine  10 . Then if joystick  22  is being directed in the direction that would bring machine  10  closer to the object (respectively steps  1108 ,  1110  or  1112 ), then the force feedback in that direction and/or the vibration actuator is activated, and may increase as the object is more closely approached. The force feedback can be in the form of an increased force feedback in the direction that relates to the position of a detected object. For example, if an object is detected on the left side, then the force feedback associated with that part of the joystick is increased. Additionally, the vibration actuator may be actuated to alert the operator that something has been detected and that machine  10  may be on a collision course with the object. 
         [0049]    While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.