System for controlling operation of mobile crane

Abstract

The present application relates to a method and a corresponding system for controlling the operation of a mobile crane, the operation comprising a user input comprising a command to change the configuration of the mobile crane, the method comprising the steps of: determining a current tipping moment of the mobile crane, the tipping moment comprises a moment around a tipping line of the mobile crane; predicting the effect of the user input on the tipping moment of the mobile crane; and altering the response to the user input if the predicted impact of the user input is increasing the tipping moment of the mobile crane by more than a predetermined amount. Another aspect relates to a user interface for displaying to a user an effect of a user input on a tipping moment of a mobile crane, the user interface displaying a safe range of the effect of the user input and a non-safe range of the effect of the user input, which may lead to a tipping of the mobile crane.

Description

[0001] This application is a divisional application of the PCT international invention patent application with application number 202080073354.2, application date October 16, 2020, and invention name “Operation Control of Mobile Crane”. Technical Field

[0002] Embodiments relate to controlling the operation of a mobile crane, particularly a pick and carry crane, and more particularly to a system for controlling the operation of a mobile crane. Background Art

[0003] A pick and carry crane is a crane that is capable of moving (i.e., traveling) while having a load suspended from the boom of the crane. Some pick and carry cranes are capable of traveling on public roads at highway speeds, where they are classified as special purpose vehicles. The design of a pick and carry crane can vary depending on the application of the crane. Some designs of pick and carry cranes allow for more operational flexibility than other crane types. For example, when a pick and carry crane is articulated, the entire crane can fit within the turning circle of the crane. This design feature can enable an articulated pick and carry crane to be used in narrow or confined spaces to lift and move loads, such as loads on the floor of a manufacturing facility.

[0004] Pick and carry cranes can also take the form of a "taxi crane", where the crane travels with all the equipment required to operate the crane within the full capabilities of the crane. Many cranes cannot operate as taxi cranes because they cannot transport all the components required for operation, so a support vehicle is often required to carry additional components such as counterweights and rigging including slings and hooks.

[0005] Typically, in a pick and carry crane, the same operator station is used to control the crane when it is traveling (such as on a public road) as when the crane is operated in a facility. This "single-chamber" arrangement helps simplify the crane configuration and provides flexibility for the operator (i.e., not having to move back and forth between the operator's cab and the crane cab).

[0006] Such pick and carry cranes have a tipping line defined by the contact point between the crane and the ground (i.e., the tires). Thus, when the moment about the tipping line is sufficient, the crane will tip or fall about the tipping line. There are many factors that affect the extent of the moment about the tipping line ("tipping moment"), such as boom extension, boom luff, load weight and weight distribution, ground inclination and crane orientation relative to that inclination, extension of the crane articulation, sway of the load, etc.

[0007] Since pick and carry cranes are often sized to fit on public roads, tipping can be a significant concern. Tipping of a crane can not only damage the crane, but it can also create significant safety issues for the operator of the tipping crane and anyone nearby who might be put in danger by the tipping crane.

[0008] With other mobile cranes, outriggers can be used to minimize susceptibility to tipping. However, such outriggers are used when the crane is operating in a stationary position. As pick and carry cranes need to travel with the load, this means that outriggers cannot usually be used.

[0009] It should be understood that reference to prior art herein does not constitute an admission that such art forms part of the common general knowledge of a person skilled in the art in Australia or any other country. Summary of the invention

[0010] Embodiments relate to a method of controlling operation of a mobile crane, the operation including user input including a command to change a configuration of the mobile crane, the method comprising the steps of:

[0011] determining a current or future tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0012] predicting the effect of user input on the tipping moment of a mobile crane; and

[0013] If the predicted effect of the user input is to increase the tipping moment of the mobile crane beyond a predetermined amount, the response to the user input is altered.

[0014] The current or future tipping moment of the mobile crane may be determined with reference to the current or future configuration of the mobile crane.

[0015] The predetermined quantity may be assessed for one or more of: one or more tipping lines of the mobile crane; the distance between the centre of gravity of the crane and the one or more tipping lines; and the load carried by the mobile crane.

[0016] If the rate of change in the configuration of the crane exceeds a predetermined rate, the response to the user input may be altered.

[0017] The configuration of a mobile crane may include the location of the center of gravity of the crane relative to one or more tipping lines of the mobile crane.

[0018] The user input may correspond to a function of the mobile crane, the function having a function speed, and wherein the response to a change in the user input may include reducing the function speed.

[0019] The functionality of user input can correspond to changes in one or more of the following:

[0020] The speed of the mobile crane;

[0021] luffing angle of the mobile crane's boom;

[0022] Extension of the boom;

[0023] The articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane;

[0024] Actuation of winches of mobile cranes;

[0025] The lateral articulation angle of the mobile crane's boom;

[0026] The pitch of the mobile crane's undercarriage; and

[0027] Tumbling of the undercarriage of a mobile crane.

[0028] The method may further comprise determining one or more of: a position, velocity and acceleration of the load or boom head; and varying a response to the user input based on the determination.

[0029] The method may also include determining an acceleration of the boom head and varying a response to the user input based on the determination.

[0030] The method may also include further altering the response to the user input if the predicted impact of the user input is to increase the tipping moment of the mobile crane beyond a further predetermined amount.

[0031] The user input comprising a command to change the configuration of the mobile crane may be a command to change the configuration of the mobile crane by a change amount. The step of changing the response to the user input may be to vary the change amount so that the tipping moment of the mobile crane remains within a predetermined amount after the configuration has been changed.

[0032] The amount of modification may vary depending on the difference between the determined tipping moment and the predetermined amount. The amount of modification may be reduced. The amount of modification may be small or zero for larger differences and may be larger for larger differences.

[0033] The method may also include predicting characteristics of terrain that the mobile crane may traverse, wherein the user input includes acceleration or deceleration, and wherein changing the response to the user input includes decreasing, increasing, or preventing acceleration or deceleration.

[0034] Another embodiment extends to a user display system for a mobile crane, the user display system comprising a user display and a configuration determiner, the user display comprising at least one display element corresponding to a feature of the mobile crane affected by a user input, each display element comprising a first portion designating a safety zone for the corresponding feature and a second portion designating a warning zone for the corresponding feature,

[0035] wherein the configuration determiner determines a current or future tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0036] predicting an effect of the user input on a tipping moment of the mobile crane; and if the predicted effect of the user input is to increase the tipping moment of the mobile crane by more than a predetermined amount, then:

[0037] designating a first range of impact of the user input as a safety range, and designating a second range of impact of the user input as a warning range;

[0038] The first portion and the second portion are displayed according to a relationship between the first range of influence and the second range of influence.

[0039] The user display may include a representation of a mobile crane. The display element may be part of the representation of the mobile crane and may represent a range of configurations that correspond to changes from the user input. The first portion and the second portion may be displayed as an overlay on the representation of the crane. The overlay may correspond to features affected by the user input. For example, where the user input in question affects boom articulation, the first and second portions may be overlaid on a representation of the range of possible boom articulations.

[0040] The system may also include updating the display in response to a change in the configuration of the crane. The change in configuration may be the result of a user input or a change in the orientation or load of the mobile crane.

[0041] The predetermined quantity may be evaluated for one or more of: one or more tipping lines of the mobile crane; the distance between the center of gravity of the crane and the one or more tipping lines; and the load carried by the mobile crane.

[0042] Mobile crane features may correspond to one or more of the following:

[0043] The speed of the mobile crane;

[0044] luffing angle of the mobile crane's boom;

[0045] Extension of the boom;

[0046] The articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane;

[0047] Actuation of winches of mobile cranes; and

[0048] The lateral articulation angle of the boom of a mobile crane.

[0049] The user display may include a plurality of display elements, each display element corresponding to a different mobile crane feature.

[0050] The at least one display element may include a rectangle, wherein the first portion and the second portion are corresponding first and second portions of the rectangle.

[0051] The relative size of the first portion of the rectangle relative to the second portion of the rectangle may be related to the size of the first range compared to the size of the second range.

[0052] The display element may include a first dimension and a second dimension, wherein the first dimension corresponds to the first user input and the second dimension corresponds to the second user input. In this embodiment, the display element will be divided into a plurality of display portions, each portion being designated as a safety type or a warning type. In one embodiment, there are a plurality of types, each type having a severity level. The display may depend on the severity level. The color of the portion may be related to the severity level.

[0053] Mobile crane features may correspond to one or more of the following:

[0054] The pitch of the mobile crane's undercarriage; and

[0055] Tumbling of the undercarriage of a mobile crane.

[0056] The user display may include a terrain display adapted to display terrain that the mobile crane may traverse, wherein the displayed terrain is divided into at least two parts, wherein a first part corresponds to a safety range for pitch and / or roll and a second part corresponds to a warning range for pitch and / or roll, and wherein the determiner is adapted to display the first part in a first color and the second part in a second color. The first color may be green and the second color may be orange.

[0057] You can also specify a third section of the display element that corresponds to the danger zone. The first section can be displayed in green. The second section can be displayed in orange. The third section can be displayed in red.

[0058] The system may also include updating the display in response to a change in the configuration of the crane. The change in configuration may be the result of a user input or a change in the orientation or load of the mobile crane.

[0059] Another embodiment extends to a method of updating a user display system for a mobile crane, the user display system comprising a user display and a configuration determiner, the user display comprising at least one display element corresponding to one or more mobile crane features affected by user input, each display element comprising a first portion specifying a safety zone for the corresponding feature and a second portion specifying a warning zone for the corresponding feature, the method comprising:

[0060] determining a current or future tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0061] predicting an effect of the user input on a tipping moment of the mobile crane; and if the predicted effect of the user input is to increase the tipping moment of the mobile crane by more than a predetermined amount, then:

[0062] designating a first range of impact of the user input as a safety range, and designating a second range of impact of the user input as a warning range;

[0063] The first portion and the second portion are displayed according to a relationship between the first range of influence and the second range of influence.

[0064] Another embodiment extends to a system for controlling operation of a mobile crane, the system comprising a user operable control that generates a user input comprising a command to actuate an actuator for changing a configuration of the mobile crane, the system further comprising a determiner adapted to:

[0065] determining a current tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0066] Predicting the effect of user input on the tipping moment of a mobile crane; and

[0067] If the predicted effect of the user input is to increase the tipping moment of the mobile crane beyond a predetermined amount, then the response to the user input command is altered.

[0068] The predetermined quantity may be evaluated for one or more of: one or more tipping lines of the mobile crane; the distance between the center of gravity of the crane and the one or more tipping lines; and the load carried by the mobile crane.

[0069] If the rate of change in the configuration of the crane exceeds a predetermined rate, the response to the user input command may be further altered.

[0070] The configuration of a mobile crane may include the location of the center of gravity of the crane relative to one or more tipping lines of the mobile crane.

[0071] The actuator actuated by the user input may correspond to a function of the mobile crane, the function having a function speed, and wherein the response to the change in the command of the user input includes reducing the function speed.

[0072] The functions entered by the user can correspond to one or more of the following:

[0073] The speed of the mobile crane;

[0074] luffing angle of the mobile crane's boom;

[0075] Extension of the boom;

[0076] The articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane;

[0077] Actuation of winches of mobile cranes;

[0078] The lateral articulation angle of the mobile crane's boom;

[0079] The pitch of the mobile crane's undercarriage; and

[0080] Tumbling of the undercarriage of a mobile crane.

[0081] The system may also include one or more sensors for determining one or more of: position, velocity and acceleration of the load or boom head, and wherein the determiner varies the response to the user input command based on the determination.

[0082] The system may also include determining an acceleration of the boom head and varying a response to the user input based on the determination.

[0083] The determiner may be adapted to further alter the response to the user input command if the predicted effect of the user input is to increase the tipping moment of the mobile crane beyond a further predetermined amount.

[0084] The system may also include predicting terrain features that the mobile crane may traverse, wherein the user input includes acceleration or deceleration, and wherein changing the response to the user input includes decreasing, increasing, or preventing acceleration or deceleration.

[0085] A mobile crane may be a pick and carry crane. A mobile crane may be a taxi crane. A mobile crane may not include outriggers. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Embodiments are described herein with reference to the accompanying drawings, in which:

[0087] Figure 1 A perspective view of an embodiment of a pick and carry crane is shown;

[0088] Figure 2 A side view of a pick and carry crane is shown;

[0089] Figure 3 and Figure 4 A top view of a pick and carry crane is shown;

[0090] Figure 5 Details of the boom attachment are shown;

[0091] Figure 6 The lateral articulation of the boom of a pick and carry crane is shown;

[0092] Figure 7 is a schematic diagram of the layout of the components of the pick-and-carry crane;

[0093] Figures 8 to 11 Various aspects of a user display for a pick and carry crane are shown. DETAILED DESCRIPTION

[0094] Figure 1 , Figure 2 and Figure 3 A pick and carry crane 10 is shown. The crane 10 has a front body 12, which is the front portion of the crane 10. The front body 12 is pivoted by a pivot arrangement 30 ( Figure 2 and Figure 3 The front body 12 is pivotally connected to the rear body 14 of the crane 10 (shown by dashed lines in FIG. 1 ). A movable linkage (in this case a hydraulic link, but other linkages are known) is provided at the pivot point 30 to control the pivot angle of the front body 12 relative to the rear body 14. Adjusting the pivot angle using the movable linkage facilitates turning the crane 10.

[0095] When the front body 12 pivots relative to the rear body 14, a rollover line 34 is defined (see Figure 4 ).

[0096] In the embodiment of the pick and carry crane 10 as shown, the rollover line 34 is an imaginary longitudinal axis extending between the point where the outer tires T1 of the front body contact the ground via wheels 20 and the point where the outer tires T3 of the rear body contact the ground via wheels 18. Thus, the tires T1 of wheels 20 and the tires T3 of wheels 18 define the point about which the crane may roll sideways. The crane 10 includes two sets of rear tires T3 and T2. In this embodiment, the frontmost set T3 is used to define the rollover line because the rearmost set T2 can be lifted during taxi mode so that those tires are no longer in contact with the road or other driving surface.

[0097] The pick and carry crane is shown as having three axles, but it will be appreciated that in different embodiments the mobile crane may have two axles or more than three axles.

[0098] A boom support arm 24 is attached to the rear end of the front body 12. The boom support arm 24 may be a separate structure mounted (e.g., welded or bolted) to the front body 12. In one embodiment, the boom support arm 24 forms part of the chassis of the front body 12. The boom support arm 24 pivotally supports a boom 26, which is pivotally connected around a pin 27 ( Figure 2 ) is raised and lowered. The boom 26 is retractable. Other forms of linear actuators and booms may be used in place of or in addition to the link 28 and the boom 26.

[0099] Figure 5 The joint between the boom 26 and the boom support arm 24 is shown. The embodiment uses boom articulation, which allows the boom to be articulated up and down as well as side to side. Figure 5 In the illustrated embodiment, the double articulated joint 40 provides two forms of articulation.

[0100] In this embodiment, lateral movement of the boom 26 is limited to 5° either side of the vertical, so that the total lateral movement of the boom is limited to 10°.

[0101] In an alternative embodiment, the total lateral movement of the boom is limited to 20°, 10° either side of the vertical.

[0102] Figure 6 The boom 26 is shown articulated laterally at an angle α. As shown, the pick and carry crane 12 is shown here on inclined terrain "G" at an angle θ relative to the horizontal. The slope of the terrain "G" will move the center of gravity away from the center of the pick and carry crane, thereby increasing the tipping moment and making the crane unstable. By articulating the boom 26 laterally as shown, the center of gravity is brought back toward the center of the crane, thereby reducing the tipping moment and potentially improving stability.

[0103] In alternative embodiments, the range of lateral movement may be set based on a number of factors, such as the maximum length of the boom when extended, the capacity of the crane, operating conditions, etc.

[0104] Hydraulic linkages 28A and 28B control the up and down articulation and the side articulation of boom 26. For certain embodiments, it may be advantageous to use hydraulic linkages to control the up and down articulation and the side articulation because known pick and carry cranes include such hydraulic linkages. Thus, there is no need to develop and install a new articulation mechanism to accommodate the side articulation in addition to the existing up and down articulation.

[0105] Features of pick and carry cranes related to the control of tipping are described in PCT / AU2014 / 000261, PCT / AU2017 / 050999, AU2018903904 and AU2019903890, the contents of which are incorporated herein. It will be appreciated that the lateral articulation of the boom as described herein may be incorporated into the anti-tip considerations and controls discussed in those applications.

[0106] Figure 7 A system 100 for controlling the operation of a mobile crane 10 is shown. The system includes two user controls 114A and 114B connected to a detector 112. Two actuators 118A and 118B are also connected to the detector 112, as are two sensors 116A and 116B. In use, a user will actuate one of the user controls 114A or 114B, which sends a command to the detector 112. The detector 112 will process the command in the manner described below and actuate the corresponding actuator as appropriate.

[0107] In the illustrated embodiment, each user control 114A and 114B corresponds to an actuator, such that user control 114A may actuate actuator 118A and user control 114B may actuate actuator 118B.

[0108] The detector 112 receives input from sensors 116A and 116B and uses the input in the following manner.

[0109] Figure 7 The user controls may correspond to controls for any of the following functions of the mobile crane 10:

[0110] The speed of the mobile crane;

[0111] The luff angle of the boom 26 of the mobile crane;

[0112] Extension of the boom 26;

[0113] The articulation of the front underframe or body 10 of the mobile crane relative to the rear underframe or body 14 of the mobile crane;

[0114] the actuation of a winch on a mobile crane; or

[0115] The lateral articulation angle of the boom 26 of the mobile crane.

[0116] The mobile crane is driven by varying speed and steering corresponding to articulation of the front chassis relative to the rear chassis. The pitch and roll of the front and rear chassis may be affected as the mobile crane travels across different terrains, and thus the pitch and roll of the front and rear chassis are additional features of the mobile crane that may be affected by user input.

[0117] Thus, user controls 114A and 114B correspond to, for example, a luff up / luff down lever or a boom extend / retract lever. The manner of controlling each of the above functions (features) of a crane is known in the art and will not be described further herein. For the present description, it is sufficient to note that each user control will actuate a corresponding actuator 118A and 118B. Each command issued by a user control will typically have a direction and magnitude associated with it.

[0118] Thus, if the user control corresponds to raise / lower), the corresponding actuators would be hydraulic links 28A and 28B.

[0119] The determiner 112 includes a central processing unit 120 connected to a memory 122. When the determiner 112 receives a command from the user control 114A, the determiner will first evaluate the current tipping moment of the crane. In this embodiment, the tipping moment is evaluated by determining the position of the center of gravity of the crane relative to the tipping line 34. It should be appreciated that there are three other tipping lines that may be relevant, see Figure 4 , four lines connect the outer tires in contact with the running surface. In practice, only the rollover line is relevant, since a mobile crane is unlikely to tip forward or backward due to its weight distribution.

[0120] Therefore, in this embodiment, the rollover moment is calculated by first determining the distance between the center of gravity and the nearest rollover line. However, in other embodiments, the calculation can be repeated for the forward and rearward rollover lines.

[0121] The location of the center of gravity may not always be known exactly. In one embodiment, the tipping moment is estimated by determining the top position of the boom based on sensor data or usage data and assuming that the load is directly below the attachment point of the boom. The vertical position of the load relative to the attachment point may be estimated based on sensor data or usage data from the winch. In one embodiment, the center of gravity is determined based on the weight of the load, the angle and extension of the boom, and the vertical height of the load.

[0122] In this embodiment, the overturning moment is calculated as follows:

[0123] The distance from the load to the tipping line is multiplied by the weight of the suspended load.

[0124] It will be appreciated that to achieve the best results both the vertical and lateral distances between the tipping line and the load are taken into account.

[0125] The determined tipping moment is then compared to a predetermined amount by the detector 112. In this embodiment, since an approximation is used, the predetermined amount is set to 90% of the rated capacity of the crane. This will provide sufficient margin to account for most errors.

[0126] The determiner will then predict the effect of the user input on the tipping moment of the mobile crane. To do this, the determiner 112 will effectively run a simulation whereby it assumes that a command corresponding to the user input is executed and determines the effect of that command on the tipping moment. To do this, the determiner stores a mathematical model of the mobile crane (including the position of the load), determines how the command will change the configuration of the crane (including the position of the load, the articulation of the crane, and (if applicable) the pitch and roll of the front and rear chassis), and then recalculates the tipping moment in the manner described above.

[0127] If the detector subsequently determines that the user's command will cause the tipping moment to exceed a predetermined amount (90% of the rated capacity), the detector will change the response to the user input. It should be recognized that the manner in which the response to the user input is changed will depend on the user input. However, in some embodiments, where the command issued by the user control has a direction and a magnitude associated with it, the detector will change one or both of the direction and the magnitude.

[0128] For example, if the operator actuates the raise / lower lever to execute a command to raise the boom 20°, and the detector determines that the command will cause the tipping moment to exceed a predetermined amount, the command may be limited to 4°. Alternatively, the detector will determine a maximum allowable value and replace that maximum allowable value.

[0129] In another example, the operator actuates a raise / lower control, but the control is limited to controlling the speed of the boom luffing and has 10 different speeds and directions (up or down). In this case, the detector can predict the impact of the command over a predetermined time (e.g., 30 seconds) and evaluate the change in the crane tipping moment over that predetermined time, and if the tipping moment exceeds a predetermined amount, for example, limit the speed of change of the boom luffing.

[0130] In another example, the time period used by the detector will depend on the assessment of the current rollover moment. If the current rollover moment is determined to be close to the predetermined amount, the time period for predicting the effect of the command will be shorter than if the current rollover moment is further away from the predetermined amount.

[0131] In another embodiment, the detector evaluates the rate of change of the tipping moment. This can more accurately determine whether the crane is in imminent danger of tipping, because especially in the case of variables such as the roll change of the chassis, if the boom is extended and has a relatively large luffing angle, the tipping moment may be affected exponentially.

[0132] In one embodiment, the velocity of the boom head is determined and used as an approximation of the rate of change of the tipping moment. If the velocity of the boom head is compared to the current tipping moment.

[0133] When determining the tipping moment as described, the position of the load needs to be known. In one embodiment, the load is assumed to be positioned vertically below the attachment point of the boom, and the attachment point of the boom is calculated using sensors that determine the angle and extension of the boom, the height of the load, and the articulation of the crane. In an alternative embodiment, the data is used to determine the current configuration of the crane (angle and extension of the crane).

[0134] In another embodiment, the crane includes sensors that determine the position, velocity and acceleration of the load, and these measurements are used to determine the tipping moment. An advantage of such an embodiment may be that any sway of the load may be determined and combined with the determination of the tipping moment. Small changes in the configuration of the crane may result in large changes in the load sway, particularly when articulated and the boom is oriented away from the rest position (no articulation, boom lowered and fully retracted).

[0135] In these cases, when the load is in a position that tends to increase the tipping moment, the determination of load swing can be used to limit the response to the user command. In one embodiment, the command is executed in a manner that can reduce the load swing, especially when the command is related to the lateral articulation of the boom.

[0136] It will be appreciated that in further embodiments, modifications may be made. For example, the detector may vary its response to the user input depending on the difference between the determined tipping moment and a predetermined amount. Thus, if the difference is large, the command corresponding to the user input is not restricted, but as the difference becomes smaller, the restriction increases until the predetermined amount has been reached, at which point the user input is completely blocked.

[0137] In some embodiments, the tipping moment may be calculated in the future. For example, if it is known that the configuration may change in the future, these changes may be taken into account when calculating the tipping moment. For example, if it is known that the configuration of the crane will change due to the characteristics of the terrain that the crane will traverse, these changes may be taken into account when calculating the tipping moment.

[0138] Figure 8A user display 130 is shown connected to the detector 100. In this embodiment, the user display 130 includes three display elements 132A, 132B, and 132C. Each display element corresponds to a different command initiated by the user input. Thus, in this embodiment, display element 132A corresponds to a raise; display element 132B corresponds to a lower; and display element 132C corresponds to a boom extension.

[0139] When the user initiates the user input, the determiner determines the current tipping moment of the mobile crane and predicts the effect of the user input on the tipping moment of the mobile crane; and determines whether the predicted effect of the user input is to increase the tipping moment of the mobile crane beyond a predetermined amount. This is done in the manner described above. The determiner then designates a first range of the effect of the user input as a safe range, and a second range of the effect of the user input as a warning range. For example, for the first range, the indicator may determine that a tipping moment within 75% of the predetermined amount is safe, and a tipping moment between 75% and 100% of the predetermined amount is a warning zone.

[0140] It will therefore be appreciated that the predetermined amount corresponds to a tipping condition for the mobile crane (in other words, a set of crane configurations where the crane is likely to tip over, taking into account such variables as swings on the load and uneven distribution of the load).

[0141] Then, the determiner divides the corresponding display element into two parts, and displays the available range of the corresponding command as the corresponding display parts, which are represented according to the relationship between the range corresponding to the safety zone and the range corresponding to the warning zone.

[0142] For example, if the user initiates a lift command, the detector will determine the amount of lift that can be safely performed and the amount by which the crane is close to tipping. For example, if the safety zone is determined to be 5° from the current position and the warning zone is 15° beyond that position, the display element 132A will be divided into two parts: 134A and 136A to show the operator the relative safety zone remaining in this operational aspect of the mobile crane.

[0143] This can provide the operator with a quick and intuitive representation of the available safe operations of the crane.

[0144] In this embodiment, the portion 136A corresponding to the warning zone is displayed in red, and the portion 134A corresponding to the safety zone is displayed in green. This allows the operator to make a more intuitive assessment.

[0145] In this embodiment, the display is continuously updated as the configuration of the crane changes. If the user's actions tend to increase the tipping moment, the user will see the corresponding warning portion of the display increase. In addition, as the configuration of the crane changes over time, the user will see the warning portion of the display change accordingly.

[0146] When representing multiple user inputs on the screen, such as Figure 8 As shown (only three examples are shown; it should be appreciated that more examples may be shown), a representation is provided to the user that can be quickly evaluated. This aspect may be usefully combined with the previous aspect of varying the response to user input. In one embodiment, as the size of the red area on the display increases, the user may experience a decrease in responsiveness to commands.

[0147] In another embodiment, the display element can be divided into three areas, and the detector calculates the safe area, the warning area and the forbidden area. In this embodiment, the part corresponding to the safe area can be represented by green, the part corresponding to the warning area can be represented by orange, and the part corresponding to the forbidden area can be represented by red.

[0148] Fig. 9 A display 160 is shown according to another embodiment. Display 160 represents the terrain over which the crane may move. This may come from map data, radar, or elsewhere. In the embodiment shown, the ground has flat portions 142 and sloped portions 144. Using the range and altitude information, the detector divides the terrain into areas that do not affect the tipping moment (area 144), areas that affect the tipping moment but are acceptable in the current configuration (area 146), and areas that will cause the crane to tip in the current configuration (area 148).

[0149] The detector classifies the terrain area by determining the effect of tilt on the pitch and roll of the front and rear chassis, calculating the tipping moment for these values ​​(assuming the rest of the configuration remains unchanged) and comparing these values ​​to predetermined values ​​(here again 90% of the rated capacity).

[0150] In one embodiment, the effect of the user input may vary depending on how close the crane configuration is to tipping or how fast the tipping moment approaches a tipping condition. It will be appreciated that this may be done with any user input, but finds particular application with those where the user can determine the rate of change as well as the direction of the change. Fig. 9 A set of examples of terrain descriptions that can reduce the impact of user input is related to the control of the speed and direction of the crane.

[0151] For example, if the user selects that the mobile crane should be subjected to maximum forward acceleration (by placing their foot flat on the accelerometer pedal), and the detector determines that there are tight undulations in the terrain (which would result in a tipping situation if the mobile crane were driven there), the detector will not provide the full acceleration to the user, but for example only half of the available acceleration.

[0152] Similar considerations may apply to steering and other changes in the configuration of the mobile crane.

[0153] It will be appreciated that the amount by which the effect of the user input is suppressed may depend on the current configuration of the mobile crane. The closer the current configuration is to a tipping state, the more limited the effect will be.

[0154] Fig.10 A display 200 according to another embodiment is shown. The display 200 includes a representation of a mobile crane. In this embodiment, the display includes a display element 202 that displays the safety zone for boom extension and luffing (together forming the radius of the load relative to the body of the crane) and crane articulation. The display element 202 has two dimensions "x" and "y", where the x dimension corresponds to the radius formed by the boom extension and luffing, and the y dimension corresponds to the articulation. As shown, the element 202 is divided into display portions 202, 204, 206, 208 and 210 that reduce the risk of crane configuration. Marking 250 displays the current position of the end of the boom and therefore represents the current configuration of the mobile crane.

[0155] Display element 202 is generated by a detector that calculates how changes to the current configuration will affect the tipping moment of the crane. Display element 202 is broken down into a series of pixels (which may or may not correspond to display pixels on an associated display), each pixel representing the radius and length of the boom. In this embodiment, each pixel represents a change of 0.1 m in radius and a change of 5° in articulation, but in other embodiments, coarser or finer resolutions may be used.

[0156] For each of these pixels, the tipping moment of the crane is calculated and classified according to the likelihood of the crane tipping in that configuration. In order to communicate the tipping likelihood to the user, each pixel is assigned a color according to the corresponding likelihood. In the illustrated embodiment, red is selected for those configurations that are almost certain to result in tipping; pink indicates that tipping is unlikely to result; light green configurations are almost certain to be safe; and dark green indicates those configurations that are safe.

[0157] If the crane is in the corresponding configuration, increasing the articulation or boom extension will tend to tip the crane, as reflected by the severity level of the section. The key 220 displays the severity level, in this case designated by the corresponding color. In the illustrated figure, the key 220 is labeled "Hook Load (Tons)". However, in this embodiment, the load weight has been determined and incorporated into the calculation of the pixel color of the display element 202. Therefore, a more correct label for the key 220 would be "Percentage Rated Capacity" as this is intended to show the relative amount of rated capacity available to the operator.

[0158] It will be appreciated that in this embodiment the detector predicts the effect that boom extension and luffing and articulation will have on the tipping moment. For the purpose of determining pixel colour it is assumed that the roll and pitch of the crane will remain constant.

[0159] However, as the roll and pitch of the crane changes, display element 202 will be updated.

[0160] Fig.11 shows a similar Fig.10 Display 300 is a display element 302 that is similar to display element 202, but for a different model of crane. Display element 302 differs from display element 202 in that the differently colored regions are not arranged symmetrically about the boom. This is because in this configuration the crane is located on uneven terrain (3° slope, as shown in display 300) so that the tipping moment is asymmetrical about the boom.

[0161] Typically, the display 200 or 300 will update as the pitch and roll of the crane changes over time to reflect to the user how changes in configuration can affect the tipping moment.

[0162] The present invention provides the following implementation modes:

[0163] Embodiment 1. A method of controlling the operation of a mobile crane, the operation comprising user input, the user input comprising a command for changing the configuration of the mobile crane, the method comprising the following steps:

[0164] determining a current tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0165] predicting an effect of the user input on the tipping moment of the mobile crane; and

[0166] If the predicted effect of the user input is to increase the tipping moment of the mobile crane beyond a predetermined amount, then a response to the user input is altered.

[0167] Embodiment 2. A method according to embodiment 1, wherein the predetermined quantity is evaluated for one or more of the following: one or more tipping lines of the mobile crane; the distance between the center of gravity of the crane and the one or more tipping lines; and the load carried by the mobile crane.

[0168] Embodiment 3. The method of embodiment 2, wherein the response to the user input is further altered if the rate of change in the configuration of the crane exceeds a predetermined rate.

[0169] Embodiment 4. The method of any preceding embodiment, wherein the configuration of the mobile crane includes a position of the center of gravity of the crane relative to one or more tipping lines of the mobile crane.

[0170] Embodiment 5. The method of any preceding embodiment, wherein the user input corresponds to a function of the mobile crane, the function having a function speed, and wherein the response to a change in the user input includes reducing the function speed.

[0171] Embodiment 6. A method according to any preceding embodiment, wherein the function of the user input corresponds to a change in one or more of the following:

[0172] the speed of the mobile crane;

[0173] the luffing angle of the boom of the mobile crane;

[0174] extension of the boom;

[0175] articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane;

[0176] actuation of a winch of the mobile crane;

[0177] the lateral articulation angle of the boom of the mobile crane;

[0178] the pitch of the undercarriage of the mobile crane; and

[0179] Tumbling of the undercarriage of the mobile crane.

[0180] Embodiment 7. The method according to any preceding embodiment, further comprising: determining one or more of: the position, velocity, and acceleration of the load or the boom head; and changing the response to the user input based on the determination.

[0181] Embodiment 8. The method of embodiment 7 further comprising determining an acceleration of the boom head and changing a response to the user input based on the determination.

[0182] Embodiment 9. The method of any preceding embodiment, further comprising: if the predicted impact of the user input is to increase the tipping moment of the mobile crane beyond a further predetermined amount, further varying the response to the user input.

[0183] Embodiment 10. A method according to any of the preceding embodiments, wherein the user input comprising a command to change the configuration of the mobile crane is a command to change the configuration of the mobile crane by a change amount, and wherein the step of changing the response to the user input comprises varying the change amount so that the tipping moment of the mobile crane remains within a predetermined amount after the configuration has been changed.

[0184] Embodiment 11. The method according to embodiment 10, wherein the modification amount varies according to the difference between the determined tipping moment and the predetermined amount.

[0185] Embodiment 12. The method of any preceding embodiment, further comprising predicting characteristics of terrain that the mobile crane can traverse, wherein the user input comprises acceleration or deceleration, and wherein changing the response to the user input comprises reducing, increasing, or preventing the acceleration or deceleration.

[0186] Embodiment 13. A user display system for a mobile crane, the user display system comprising a user display and a configuration determiner, the user display comprising at least one display element corresponding to one or more mobile crane features affected by the user input, each display element comprising a first portion specifying a safety zone for the corresponding feature and a second portion specifying a warning zone for the corresponding feature,

[0187] wherein the configuration determiner determines a current tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0188] predicting an effect of the user input on the tipping moment of the mobile crane; and if the predicted effect of the user input is to increase the tipping moment of the mobile crane by more than a predetermined amount, then:

[0189] designating a first range of influence of the user input as a safety range, and designating a second range of influence of the user input as a warning range;

[0190] The first portion and the second portion are displayed according to a relationship between the first range of influence and the second range of influence.

[0191] Embodiment 14. The system of embodiment 13 further comprises updating the display in response to a change in the configuration of the crane.

[0192] Embodiment 15. A system according to embodiment 13 or 14, wherein the predetermined quantity is evaluated for one or more of the following: one or more rollover lines of the mobile crane; the distance between the center of gravity of the crane and the one or more rollover lines; and the load carried by the mobile crane.

[0193] Embodiment 16. The system of any preceding embodiment, wherein the mobile crane feature corresponds to one or more of:

[0194] the speed of the mobile crane;

[0195] the luffing angle of the boom of the mobile crane;

[0196] extension of the boom;

[0197] articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane;

[0198] actuation of a winch of the mobile crane; and

[0199] The lateral articulation angle of the boom of the mobile crane.

[0200] Embodiment 17. The system of embodiment 16, wherein the user display includes a plurality of display elements, each display element corresponding to a different mobile crane feature.

[0201] Embodiment 18. A system according to any one of Embodiments 13 to 17, wherein at least one display element comprises a rectangle, and wherein the first portion and the second portion are corresponding first and second portions of the rectangle.

[0202] Embodiment 19. A system according to embodiment 18, wherein the relative size of the first portion of the rectangle with respect to the second portion of the rectangle is related to the size of the first range compared to the size of the second range.

[0203] Embodiment 20. The system of any one of Embodiments 13 to 19, wherein the mobile crane feature corresponds to one or more of:

[0204] the pitch of the undercarriage of the mobile crane; and

[0205] Tumbling of the undercarriage of the mobile crane.

[0206] Embodiment 21. A system according to embodiment 20, wherein the user display includes a terrain display, the terrain display being suitable for displaying terrain that the mobile crane can traverse, wherein the displayed terrain is divided into at least two parts, wherein a first part corresponds to a safety range for pitch and / or roll, and a second part corresponds to a warning range for pitch and / or roll, and wherein the detector is suitable for displaying the first part in a first color and the second part in a second color.

[0207] Embodiment 22. A system for controlling operation of a mobile crane, the system comprising a user operable control that generates a user input comprising a command to actuate an actuator for changing a configuration of the mobile crane, the system further comprising a determiner adapted to:

[0208] determining a current tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane;

[0209] predicting an effect of the user input on the tipping moment of the mobile crane; and

[0210] If the predicted impact of the user input is to increase the tipping moment of the mobile crane beyond a predetermined amount, a response to the user input command is altered.

[0211] Embodiment 23. A system according to embodiment 22, wherein the predetermined quantity is evaluated for one or more of the following: one or more rollover lines of the mobile crane; the distance between the center of gravity of the crane and the one or more rollover lines; and the load carried by the mobile crane.

[0212] Embodiment 24. The system of embodiment 23, wherein the response to the user input command is further altered if the rate of change in the configuration of the crane exceeds a predetermined rate.

[0213] Embodiment 25. The system of any one of Embodiments 22 to 24, wherein the configuration of the mobile crane includes a position of the center of gravity of the crane relative to one or more tipping lines of the mobile crane.

[0214] Embodiment 26. A system according to any one of Embodiments 22 to 25, wherein the actuator actuated by the user input corresponds to a function of the mobile crane, the function having a function speed, and wherein the response to the change in the command of the user input includes reducing the function speed.

[0215] Embodiment 27. The system of any one of Embodiments 22 to 26, wherein the function of the user input corresponds to one or more of the following:

[0216] the speed of the mobile crane;

[0217] the luffing angle of the boom of the mobile crane;

[0218] extension of the boom;

[0219] articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane;

[0220] actuation of a winch of the mobile crane;

[0221] the lateral articulation angle of the boom of the mobile crane;

[0222] the pitch of the undercarriage of the mobile crane; and

[0223] Tumbling of the undercarriage of the mobile crane.

[0224] Embodiment 28. A system according to any one of embodiments 22 to 27, further comprising one or more sensors for determining one or more of: the position, velocity, and acceleration of the load or the boom head, and wherein the detector changes its response to the command input by the user based on the determination.

[0225] Embodiment 29. The system of embodiment 28 further comprising determining an acceleration of the boom head and changing a response to the user input based on the determination.

[0226] Embodiment 30. A system according to any one of Embodiments 22 to 29, wherein the detector is adapted to further alter the response to the user input command if the predicted impact of the user input is to increase the tipping moment of the mobile crane beyond a further predetermined amount.

[0227] Embodiment 31. A system according to any one of Embodiments 22 to 30, further comprising predicting characteristics of terrain that the mobile crane can traverse, wherein the user input includes acceleration or deceleration, and wherein changing the response to the user input includes reducing, increasing, or preventing the acceleration or deceleration.

[0228] Embodiment 32. The method of any one of Embodiments 1 to 12, wherein the method is a method of operating a pick and carry crane.

[0229] Embodiment 33. A pick and carry crane comprising a user display system according to any one of Embodiments 13 to 21.

[0230] Embodiment 34. A pick and carry crane comprising a system for controlling the operation of a mobile crane according to any one of Embodiments 22 to 31.

Claims

1. A system for controlling the operation of a mobile crane, the system comprising a user operable control generating a user input comprising a command to actuate an actuator for changing a configuration of the mobile crane, the system further comprising a detector adapted to: determining a current tipping moment of the mobile crane, the tipping moment comprising a moment about a tipping line of the mobile crane; predicting an effect of the user input on the tipping moment of the mobile crane; and If the predicted impact of the user input is to increase the tipping moment of the mobile crane beyond a predetermined amount, a response to the user input command is altered.

2. The system according to claim 1, wherein: The predetermined quantity is evaluated for one or more of: one or more tipping lines of the mobile crane; a distance between the center of gravity of the crane and the one or more tipping lines; and a load carried by the mobile crane.

3. The system according to claim 2, wherein: If the rate of change in the configuration of the crane exceeds a predetermined rate, the response to the user input command is further altered.

4. The system according to any one of claims 1 to 3, wherein: The configuration of the mobile crane includes the location of the center of gravity of the crane relative to one or more tipping lines of the mobile crane.

5. The system according to any one of claims 1 to 4, wherein: The actuator actuated by the user input corresponds to a function of the mobile crane, the function having a function speed, and wherein the response to the change in the command of the user input includes reducing the function speed.

6. The system according to any one of claims 1 to 5, wherein: The function of the user input corresponds to one or more of the following: the speed of the mobile crane; the luffing angle of the boom of the mobile crane; extension of the boom; articulation of the front underframe of the mobile crane relative to the rear underframe of the mobile crane; actuation of a winch of the mobile crane; the lateral articulation angle of the boom of the mobile crane; the pitch of the undercarriage of the mobile crane; and Tumbling of the undercarriage of the mobile crane.

7. The system of any one of claims 1 to 6, further comprising one or more sensors for determining one or more of: position, velocity and acceleration of the load or the boom head, and wherein: The determiner changes a response to the user-input command based on the determination.

8. The system of claim 7, further comprising determining an acceleration of the boom head and varying a response to the user input based on the determination.

9. The system according to any one of claims 1 to 8, wherein: The determiner is adapted to further alter the response to the user input command if the predicted effect of the user input is to increase the tipping moment of the mobile crane beyond a further predetermined amount.

10. The system of any one of claims 1 to 9, further comprising predicting features of terrain that the mobile crane can traverse, wherein The user input comprises an acceleration or a deceleration, and wherein changing the response to the user input comprises decreasing, increasing or preventing the acceleration or the deceleration.

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