Surveying system and method using mobile work machine

A surveying system is provided having a work machine with at least one sensor configured to produce a signal indicative of a longitudinal pitch of the work machine and a lateral roll of the work machine. The work machine additionally includes a locating device configured to determine the location of the work machine, a communicating device configured to communicate over a network, and a controller in communication with the at least one sensor and the locating device. The controller is configured to receive the signals from the at least one sensor, create survey data by linking the signals with the location of the work machine, and communicate the survey data using the communicating device over the network to one or more offboard controllers. At least one offboard controller is configured to compare the survey data to one or more threshold values, calculate variances, and generate a map displaying the variances.

TECHNICAL FIELD

The present disclosure relates generally to a surveying system and method using a mobile work machine, and more particularly, to a surveying system and method that can be used to survey roadways and other surfaces using a work machine having one or more sensors.

BACKGROUND

Maintaining the proper cross slope and longitudinal slope of a roadway is important for water drainage and safe operation of vehicles on the roadway, particularly in mining and construction environments. Cross slope is the transverse slope of the road surface, extending laterally and measured relative to the horizon. Cross slope measures the crown of a roadway, which generally includes a high point at the center and downwardly-sloping sides when viewed as a lateral cross section. Proper cross slope provides a gradient for water runoff into a drainage system such as a street gutter or ditch. Longitudinal slope, by comparison, is the slope of the roadway with respect to the direction of travel relative to the horizon. Longitudinal slope measures the grade of the roadway over a distance traveled, which affects the load on work machines carrying heavy cargo. Traditional methods of measuring cross slope and longitudinal slope include dispatching survey crews to manually measure points along the roadway. This technique is useful but requires a human crew to mark individual points along the roadway one point at a time, which is time consuming and slow.

One method of gathering roadway data using vehicle sensors is described in U.S. Patent Application Publication No. 2006/0276939 (the '939 publication), published to Ameen on Dec. 7, 2006. The '939 publication describes a method, apparatus, and system for estimating a grade angle and superelevation angle of a roadway using a vehicle equipped with accelerometers and a yaw rate sensor. Data from these sensors is used to calculate the estimated grade angle and superelevation angle (e.g., bank angle) of the roadway being traversed by the vehicle.

Although the '939 publication provides a means to estimate the grade angle and superelevation angle, it does not disclose using sensors from a work machine. Nor does the '939 publication disclose generating a real-time map of cross-slope and longitudinal slope variances.

The disclosed system is directed to overcoming one or more of the problems set forth above.

SUMMARY OF THE INVENTION

In one aspect, the present disclosure is directed to a surveying system that includes a work machine having at least one sensor configured to produce a signal indicative of a longitudinal pitch of the work machine and a signal indicative of a lateral roll of the work machine. The system also includes a locating device disposed on the work machine configured to determine the location of the work machine, a communicating device disposed on the work machine configured to communicate over a network, and a controller disposed on the work machine and in communication with the at least one sensor and the locating device. The controller is configured to receive the signals from the at least one sensor, create survey data by linking the signals with the location of the work machine, and communicate the survey data using the communicating device over the network to one or more offboard controllers. The at least one offboard controller is configured to compare the survey data to one or more threshold values and calculate variances, and generate a map displaying the variances.

In another aspect, the present disclosure is directed to a method of surveying that includes receiving signals from at least one sensor on a work machine, the at least one sensor configured to produce a signal indicative of a longitudinal pitch of the work machine and a signal indicative of a lateral roll of the work machine. The method further includes receiving a location of the work machine, creating survey data by linking the signals with the location of the work machine, and communicating the survey data over a network.

In yet another aspect, the present disclosure is directed to a method of surveying that includes receiving sensor data from at least one sensor on a work machine, the at least one sensor configured to produce a signal indicative of a longitudinal pitch of the work machine and a signal indicative of a lateral roll of the work machine. The method further includes receiving a location of the work machine linked to each of the sensor data, comparing the sensor data to one or more threshold values and calculating variances, and generating a map of the variances based on the location of the work machine for each sensor data.

DETAILED DESCRIPTION

FIG. 1illustrates an exemplary disclosed work machine10. In the depicted example, the work machine10is a motor grader. As a motor grader, the work machine10may include a steerable front frame12, and a driven rear frame14that is pivotally connected to the front frame12. The front frame12may include a pair of front wheels16(or other traction devices), and support a cabin18. The rear frame14may include compartments20for housing a power source (e.g., an engine) and associated cooling components, the power source being operatively coupled to rear wheels22(or other traction devices) for primary propulsion of the work machine10. The rear wheels22may be arranged in tandems at opposing sides of the rear frame14. Steering of the work machine10may be a function of both front wheel steering and articulation of the front frame12relative to the rear frame14.

The motor grader may also include a ground-engaging work tool such as, for example, a moldboard blade24(e.g., a motor grader blade). The moldboard blade24may be operatively connected to and supported by the front frame12. In the disclosed embodiment, the moldboard blade24is suspended from a general midpoint of the front frame12, at a location between front and rear wheels16,22. It is contemplated that the moldboard blade24, however, may be alternatively be connected to and supported by another portion of the work machine10, such as by another portion of front frame12and/or rear frame14.

As shown inFIGS. 1 and 2, as the work machine10travels about a worksite or otherwise across a distributed area, the work machine10can communicate with one or more offboard controllers55,56using a communicating device38and transmit location signals using a locating device36. The locating device36may include a Global Navigation Satellite System (GNSS)48, a land-based cellular network, a local laser tracking system, or another type of positioning device or system may monitor the movements of the work machine10and generate signals indicative of its position. The position signals may be directed to a controller34for processing in conjunction with sensor data, or the position signals may be sent only to one or more of the offboard controllers55,56.

The communicating device38may include hardware and/or software that enables sending and receiving of data messages over a wireless network40. The communicating device38may also facilitate communication between the controller34and/or between the controller34and one or more of the offboard controllers55,56. This communication may include, for example, the coordinates, speeds, and/or route of the work machine10generated based on signals from locating device36. The communication may also include data messages including sensor data taken and processed by the controller34for further processing by the one or more offboard controllers55,56. Data messages may be sent and received via the wireless network40. The wireless communications may include satellite, cellular, infrared, and any other type of wireless communications that enable communicating device38to exchange information between one or more of the offboard controllers55,56and the controller34of the work machine10.

Controller34may embody a single microprocessor or multiple microprocessors that include a means for processing data received from sensors on the work machine10. Numerous commercially available microprocessors can be configured to perform the functions of controller34. Controller34may include a memory, a secondary storage device, a processor, and any other components for running an application. Various other circuits may be associated with controller34such as power supply circuitry, signal conditioning circuitry, solenoid driver circuitry, and other types of circuitry.

The work machine10includes at least one sensor configured to produce a signal indicative of a longitudinal pitch of the work machine10and the lateral roll of the work machine10while the work machine10is mobile. The signals generated by the at least one sensor are communicated to the controller34for processing or for transmission to the one or more offboard controllers55,56.FIG. 3illustrates the disclosed embodiment, in which one more sensors are provided on the motor grader. The sensors may include a single multi-axis inertial measurement unit70configured to produce a signal indicative of the longitudinal pitch of the work machine10and a signal indicative of the lateral roll of the work machine10. Inertial measurement units are self-contained sensor systems capable of generating signals indicative of linear and angular motion. A multi-axis inertial measurement unit70includes two or more gyroscopes and accelerometers for measuring linear and angular motion in at least two dimensions (e.g., along two axes). In the disclosed embodiment, the axes of the multi-axis inertial measurement unit70are aligned with the longitudinal axis and the lateral axis of the work machine10to generate signals indicative of the longitudinal pitch and lateral roll of the work machine10.

Alternatively, the sensors may include a single-axis inertial measurement unit70configured to produce the signal indicative of the longitudinal pitch of the work machine10, and a blade slope sensor72configured to produce a signal indicative lateral slope of the moldboard blade24. The axis of the single-axis inertial measurement unit70is aligned with the longitudinal axis of the work machine10to generate signals indicative of the longitudinal pitch of the work machine10, while the blade slope sensor72generates signals indicative of the lateral roll of the work machine10when the moldboard blade24is aligned with a lateral axis of the work machine10.

In yet another embodiment, the sensors may include the single-axis inertial measurement unit70, the blade slope sensor72, and a rotation sensor71configured to produce a signal indicative of the angle of the moldboard blade24relative to the front frame12and lateral axis of the work machine10. The rotation sensor71produces a signal indicative of the direction of the moldboard blade24relative to the travel of the work machine10. The rotation sensor71can be used in conjunction with the blade slope sensor72to determine the lateral roll of the work machine10when the moldboard blade24is aligned with the lateral axis of the work machine10, ensuring the signals from the blade slope sensor72are measuring the slope of a roadway that is perpendicular to the direction of travel.

Finally, the sensors may additionally include a pressure sensor73. The pressure sensor73is configured to produce a signal indicative of the moldboard blade24when contacting a ground surface, thereby signaling that the moldboard blade24is flush with the ground and measuring its profile.

Data is communicated from the work machine10and to one or more offboard controllers55,56for further processing using the communicating device38. The offboard controllers55,56may include any suitable means for monitoring, recording, storing, indexing, processing, and/or communicating various operational aspects the work machine10. These means may include components such as, for example, a memory, one or more data storage devices, a central processing unit, or any other components that may be used to run an application. Furthermore, although aspects of the present disclosure may be described generally as being stored in memory, one skilled in the art will appreciate that these aspects can be stored on or read from different types of computer program products or computer-readable media such as computer chips and secondary storage devices, including hard disks, floppy disks, optical media, CD-ROM, or other forms of RAM or ROM.

The offboard controllers55,56may be configured to execute instructions stored on computer readable medium to process sensor and location data from the work machine10, create alert based on that data, and dispatch additional work machines to address problems with the roadway derived from the data. The offboard controllers55,56may include a single offboard controller for communicating with the work machine10and for processing the data, or the offboard controllers55,56may include a first offboard controller55for communicating with the work machine10and second offboard controller56for processing the data. In the latter case, data may be transmitting from the first offboard controller55to the second offboard controller56for processing, while the second offboard controller56is not in direct communication with the work machine. This allows the second offboard controller56to be dedicated to processing and handling the data, while the first offboard controller55communicates with the work machine10. In either embodiment, each of the offboard controllers55,56may include a singular computer system or a plurality of networked computer systems.

The offboard controllers55,56may communicate with the work machine10and process data from the work machine10either entirely independently from human control, or in some hybrid form. In the disclosed embodiment, the data is processed by one or more of the offboard controllers55,56and a display is provided for generating visual output for human interrogation. The data includes survey data, in which sensor data indicating roadway measurements (e.g., cross slope and longitudinal slope) are linked to location data. A map of the survey data is provided on the display (seeFIG. 6) for providing a visual depiction of the survey data and for further human analysis.

As illustrated inFIGS. 1 and 2, the work machine10may include a motor grader or any other type of work machine with sensors configured to generate signals indicative of the pitch and roll of the work machine as it moves along a roadway surface. The work machine10may also be any machine with work tools and sensors configured to generate signals based on the position of the work tools, where the work tools can be oriented so as to indicate the pitch and roll of the work machine10.

INDUSTRIAL APPLICABILITY

The disclosed surveying system may be applicable to any work machine that includes sensors capable of generating signals indicative of the longitudinal pitch and lateral roll of the work machine. The disclosed surveying system allows a roadway to be surveyed by a mobile work machine as it moves along the roadway surface. This reduces the need for roadside surveying crews. The surveying system employs sensors on a work machine to determine the longitudinal slope82and cross-slope80of a roadway90(seeFIGS. 4 and 5), and communicate that data to one or more offboard controllers for processing. The system may improve real-time monitoring of roadway conditions on a worksite or across a distributed area (e.g., across a county, etc.). In the disclosed embedment, the roadway includes a gravel, dirt, or otherwise unpaved surface, including one that may be at a worksite. The operation of surveying system will now be explained.

As shown inFIGS. 4 and 5, the surveying system of the present disclosure is configured to utilize sensors on a work machine10to determine the longitudinal slope82and cross-slope80of a roadway90. The one or more sensors generate signals indicative of the pitch and roll of the work machine10, which indicate the longitudinal slope82and cross-slope80of the roadway90. The sensors gather data and include a sampling rate that allows longitudinal slope82and cross-slope80of the roadway90to be determined at numerous points along a section of travel. This allows operators to determine where the roadway is within specifications, and where variances occur outside of allowable ranges. In particular, the longitudinal slope82and cross-slope80of the roadway90can be compared to one or more threshold values in order to calculate variances. Those variances can then be used to determine where repairs may be necessary along the roadway90.

The one or more sensors of the work machine10generate the signals indicative of the pitch and roll of the work machine10, which are communicated to the controller34. The controller uses the communicating device38to transmit those signals to one or more offboard controllers55,56. The controller34also receives location data from the locating device36, and uses the location data to link the position of each sensor data point. Therefore, the pitch and roll of the work machine is measured and tagged to a position to create survey data. In the disclosed embodiment, the survey data is created by the controller34before it is transmitted to one or more of the offboard controllers55,56. However, the signals indicative of the pitch and roll of the work machine10and the position data may be sent separately in some embodiments for processing by one or more of the offboard controllers55,56.

The signals indicative of pitch and roll of the work machine10indicate the longitudinal slope82and cross-slope80of the roadway90as the work machine10travels down the roadway. Roll of the work machine10, as illustrated inFIG. 4, is measured as an angle between a lateral axis67of the work machine10and the horizon. Roll of the work machine10can also be measured as an angle between a vertical axis65of the work machine10and a vertical line in a plane defined between the lateral axis67and vertical axis65of the work machine10. When the work machine10is level and the sensors are aligned with a longitudinal axis66and a lateral axes67of the work machine10, where roll of the work machine10indicates the cross-slope80of the roadway90.

Pitch of the work machine10, as illustrated inFIG. 5, is measured as an angle between the longitudinal axis66of the work machine10and the horizon. Pitch of the work machine10can also be measured as an angle between the vertical axis65of the work machine10and a vertical line in a plane defined between the longitudinal axis66and vertical axis65of the work machine10. As with the cross-slope, when the work machine10is level and the sensors are aligned with the longitudinal and lateral axes66,64of the work machine10, the pitch of the work machine10indicates the longitudinal slope82of the roadway90.

In processing the longitudinal slope82and cross-slope80of the roadway90, this data is linked to location data so that longitudinal slope82and cross-slope80can be analyzed and presented with reference to location along the roadway90. The controller34receives the signals from the at least one sensor on the work machine10, creates survey data by linking the signals with the location of the work machine10, and communicates the survey data using the communicating device38over the network40to one or more offboard controllers55,56. At least one of the offboard controllers55,56processes the survey data by first receiving it, either directly from the communicating device38or from another intermediate source. After receipt, data at each location along the roadway90is compared to one or more threshold values or ranges (e.g., threshold longitudinal slope and threshold cross-slope) to calculate a variance. The variance is the difference between the indicated longitudinal slope or cross-slope from a maximum allowable value, a mean value, or desired value. As shown inFIG. 6, a map101of the variances103is generated for each location along the roadway90, in which the variances103are overlaid onto the roadway90. The generated map101may be presented as a heat map, providing a visual indication of the magnitude of the variances103at all locations for which survey data is available. The color, line weight102, or alternative variable related to the overlaid variances103may vary with the magnitude of the variance103.

The threshold values represent predetermined longitudinal slope and cross-slope values for different points along the roadway90. The predetermined values may be desired or intended longitudinal slope and cross-slope of the roadway for particular points along a roadway, within a worksite, or in a particular region (e.g., for all roadways within a particular county, etc.). The threshold values may be set by an administrator of the surveying system and may reflect government, administrative, industry, or organization standards. The predetermined values may also be derived from other sources or be determined based on a given section of roadway taking into account safety, the roadway environment, and the vehicles that will use the roadway. The threshold values may be set and may be changed using the one or more offboard controllers55,56, and set during and/or after the work machine10traverses a particular roadway, collects data, and transmits the data to the one or more offboard controllers55,56. The threshold values may also be changed after the longitudinal slope and cross-slope data has been gathered to change the map101and engage in further analysis. The threshold values are used as a measure of the maximum and/or minimum allowable longitudinal slope and cross-slope, and thus are used to control the shape of the roadway.

In the disclosed embodiment, the map101is generated on a display and within a user interface100. The user interface100is a dashboard in which a human operator can view the map101of the survey data and take additional action. The map101is preferably dynamically updated as survey data is received, both for new locations for which no survey data exists, and for locations with preexisting survey data. From the user interface100, the operator may initiate an alert if the variances103exceed an alert threshold. Alternatively the offboard controller processing the data may automatically initiate the alert. In addition, the user interface100may allow the operator to communicate instructions dispatching one or more work machines to one or more locations in which the variances103exceed a repair threshold. For human operator initiated requests, an initiate alert button120and dispatch button121may be provided. However, these functions may also be automatically initiated by the offboard controller without human intervention or human request, and based solely or in part on the survey data being received.

The user interface100may provide additional information to a human operator via the display. In particular, the path of a particular work machine and the work machine details130can be viewed. The usage of the work machine131can be viewed. The user interface100may also allow the human operator to track more than one work machine10, initiate alerts, and dispatch one or more assets on demand.

In instances in which a motor grader with a moldboard blade24is employed as the work machine10, it may be necessary for further processing to be conducted in order to calculate the longitudinal slope82and cross-slope80of the roadway90. In particular, if the sensors measuring the moldboard blade24are employed, and the moldboard blade24is not aligned with the lateral axis of the motor grader, additional calculations will be necessary to derive the longitudinal slope82and cross-slope80of the roadway90. In particular, the at least one offboard controller may be further configured to correlate the signal indicative of a longitudinal pitch of the work machine10to a longitudinal slope82of the roadway and correlate the signal indicative of a lateral roll of the work machine10to cross slope80of the roadway by accounting for the moldboard blade24position. After this, the variances103can be calculated

Several advantages over the prior art may be associated with the survey system of the present disclosure. These include leveraging existing sensors on work machines to survey a worksite or a distributed roadway network, and using a mobile machine rather than human survey crews to create survey data. The use of sensors on a work machine allow data to be gathered over a broad area swiftly and economically, where real-time updates can be made and viewed from a remote location. This allows road conditions to be monitored and addressed, improving production and safety. Worksite, construction, and municipal operators would benefit from the disclosed survey system.

It will be apparent to those skilled in the art that various modifications and variations can be made to the surveying system. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed surveying system. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.