Construction site monitoring system

A job site monitoring system includes a tower-mounted scanner that is situated to monitor all or substantially all of a particular construction site. The scanner is configured to provide data to a processor configured to determine the height of fill material deposited at a job site. The processor is adapted to communicate with a remote client who can review the data collected at the job site. The processor may also be configured to compare the live fill height data to predetermined parameters to determine whether an error condition exists. An alert may be issued upon detection of such an error to enable corrective action to be taken before construction continues at the site.

BACKGROUND

The present disclosure relates to construction sites, ranging from the construction of mechanically stabilized (MSE) systems to road construction to commercial or residential building construction. Most construction sites involve several sub-contractors who report to a general contractor who bears overall responsibility for the completion of the construction project. While the general contractor continuously monitors the activities and work product of the sub-contractors, it is still difficult to find all the errors, accidental or deliberate, that can occur. In particular, it is often difficult to ensure that every aspect of a construction job is performed according to the specifications and plans for the job. The problem is particularly difficult when the general contractor is faced with sub-contractors trying to short-cut the process.

FIG. 1depicts a typical MSE wall installation which includes a plurality of reinforcement straps projecting into several levels of reinforced fill. In the typical MSE construction, each layer of back fill must be compacted to a predetermined thickness in order to ensure the proper structural integrity to both support the MSE wall and anchor the reinforcement straps. Improper compaction can lead to a loose back fill that is unable to prevent movement of the reinforcement straps. Eventually the reinforcement straps can work loose in the back fill with the potential of a catastrophic failure of the MSE wall.

In the typical MSE job site, each layer of fill is dumped at the site at a depth of fill or backfill height”, which is the height of the loose fill material after it has been leveled but before compaction. Many regulations, such as promulgated by state or federal departments of transportation, require the backfill height to be no more than 12 inches. The backfill is then compacted to another regulated height, typically 8 inches. Once one layer of backfill has been fully compacted, the next layer is dumped and graded, and the compaction process is repeated. The reinforcement straps are added at particular layers.

The leading causes of failures of MSE walls are:poor geometrypoor or inadequate backfill placementpoor or inadequate compactioninexperienced installation contractors.

Most regulatory agencies have inspectors that monitor all MSE construction sites, but the inspectors cannot be everywhere at all times. Poor backfill processes are not necessarily easily detected by visual inspection of the site throughout the construction process. In spite of diligent inspections MSE wall systems can fail due to poor construction.

Consequently, there is a need for a system that can continuously monitor a construction job site to spot errors interactively. Such a system could be used to stop the improper construction in god time to effect remedial treatment of the job site. This will avoid hidden defects that come to light much later after the construction is complete. Such a system would also catch poor construction early enough in the process so that remediation is relative simple and inexpensive.

SUMMARY

A job site monitoring system includes a tower-mounted scanner that is situated to monitor all or substantially all of a particular construction site. The scanner is configured to provide data to a processor configured to determine the height of fill material deposited at a job site. The processor is adapted to communicate with a remote client who can review the data collected at the job site. The processor may also be configured to compare the live fill height data to predetermined parameters to determine whether an error condition exists. An alert may be issued upon detection of such an error to enable corrective action to be taken before construction continues at the site.

DETAILED DESCRIPTION

The job site monitoring system of the present disclosure utilizes one or more site monitoring subsystems10shown inFIG. 2. the sub-system includes a mobile tower12that supports a scanner15. The tower is configured to be placed at a job site with the scanner15elevated high enough to survey the entirety of or some portion of the job site. Thus, as depicted inFIG. 3, the scanner15is elevated at a height, such as 100 ft., and positioned so that a 3-D beam transmitted by the scanner can provide coverage of a large area. The subsystem may further include a GPS antenna16that can be used to establish the location of the subsystem10in global coordinates. A light17and a security camera18may also be supported on the tower12and arranged so that the field of view of the camera coincides with the scan pattern of the scanner15so that all three components are surveying the same region of the job site. The camera field of view is preferably large enough to entirely encompass the scanned region of the job site.

The subsystem may incorporate solar panels19mounted on the tower to provide power to at least the four components15,16,17,18mounted at the top of the tower. The solar panels may also provide power to the control module20situated at the base of the tower. The control module includes a processor22that can communicate with the four components15,16,17,18at the top of the tower. The components may thus be wired directly to the processor22or may communicate via a wireless communication module28, which can be a Bluetooth module or module capable of wireless communication between nearby components.

The control module20may further include a cellular modem24adapted for cellular communication to a telephone system, and a WiFi modem26or other IEEE 802.11 standard transmitter capable of wireless connection to a remote network, such as the Internet or the “Cloud”. The processor may thus be configured for cloud computing as a means to provide remote access to data generated by the subsystem10at a job site. The control module20may include its own power supply30that may be provided in lieu of or in addition to the solar panels to provide power to the processor and/or the tower mounted components.

The subsystem10is configured to operate continuously, at least during working hours at the job site. The scanner15and security camera18are thus configured to continuously transmit signals to the processor22indicative of the data generated by the component. For instance, the security camera transmit video images to the processor, and preferably digital video images that can be readily stored and accessed, either on the processor, on a remote storage medium, or in the Cloud.

The heart of the subsystem10is the scanner15. The scanner is configured to accurately determine the geometry of the features at the job site. For instance, the scanner can generate digital 3-D data concerning the geometry of the MSE wall that can be used to verify that the MSE wall is being properly constructed according to the job site blueprints. Perhaps more importantly, the scanner can generate data indicative of the height of fill added to the job site. This height data can be used to calculate the backfill height as well as the compaction height which data can then be compared to the job site specifications, such as dictated by DOT regulations. The scanner may also be configured to generate data indicative of the material being scanned.

In one embodiment, the scanner is an OPAL™ 3D laser scanner or LIDAR (light detection and ranging) device, sold by Neptec Technologies Group. The OPAL™ 3D LIDAR incorporates obscurant-penetrating technology and is designed to operate in harsh environments where the scanner may be subjected to significant amounts of dust, vibration, shock, and wide operating temperature ranges. The OPAL™ sensor uses a 1540 nm pulsed laser and a fast canning Risley prism design to produce up to 200,000 points-per-second data acquisition. The scan pattern or the laser avoids data gaps so that the entire job site can be accurately scanned. The scanner15generates digital data points for a 3D representation of the job site based on the reflected laser beam across the scan pattern. The digital data can be manipulated by the processor22or remotely to focus on specific areas of the job site, such as a particular backfill operation at the job site. This 3D digital data allows a client to extract relevant information automatically and interactively as the work progresses at the job site. For instance, the 3D data generated by the OPAL™ scanner can be used to calculate backfill height per lift and compacted height by comparing the current height of the fill to a previously acquired height of the fill. Once it is calibrated, the scanner15can determine height of objects, such as back fill, based on the differential timing of the reflected laser beam relative to the calibrated or baseline timing.

It can be appreciated that since the data acquisition process is continuous, the data obtained at any particular time may not be indicative of the true backfill height or compacted height. For instance, when the backfill is initially introduced to the job site it will necessarily be mounded. The backfill height at this point in time would necessarily be outside specifications. During the construction process this mound of backfill is graded and leveled to the true backfill height. The processor can evaluate the trends in the backfill height for a given lift and determine when the change in backfill height over some time unit is essentially zero. The same process can be used to ensure an accurate compacted height. Thus, in one embodiment, the processor22is operable to evaluate the incremental change in measured height and establish a stable, or substantially uniform or unchanging height value when the incremental change is zero or within a small tolerance.

The OPAL™ scanner and associated 3D processing software can also be configured for object recognition and tracking. The processor may thus be loaded with object parameters representative of objects normally encountered at a construction job site, such as earth moving equipment and workers. The scanner may thus determine that the backfill is being graded and leveled upon detection of a grader at the job site. Once the grader leaves the area under surveillance the processor can determine that the grading process is complete and measure a true backfill height. A similar process can be used to determine the true compacted height. The processor22may also be configured to determine the reflectivity of the material being scanned and ascertain the material composition based on that reflectivity. In particular, certain materials may scatter the laser beam so that the reflected beam is of much lower intensity than the original scanning beam. The degree of reflected intensity can be correlated to materials typically found at a job site, such as aggregate, dirt, concrete and steel.

As depicted inFIG. 3, the scanner15of subsystem10scans the job site in which an MSE wall construction is occurring. The processor22of the subsystem receives the 3D data from the scanner and executes software instructions operable to process the data to generate the desired information. This information is then transmitted view cellular or WiFi to the computers or handheld devices of one or more clients or stakeholders. The client(s) can then take appropriate action. For instance, if the client is a general contractor, the contractor can contact the site supervisor to notify him/her of a problem in the construction, such as an inadequate backfill or compaction. A DOT inspector might take similar action and then evaluate later data from the subsystem10to verify that remedial action has been taken. Alternatively, the client might be the subcontractor task with constructing the MSE wall. The data acquired from the subsystem10might be used to verify that the construction was according to specifications. The subcontractor might also use the data to gauge the performance of a particular crew.

The processor22can acquire the information from the scanner15and the camera18to provide images to the client as shown inFIG. 4. The left image is the digital representation of the job site acquired by the scanner15, while the camera view is shown in the image at the right. These same images can be manipulated by a client to focus on an area of interest as denoted by a rectangle superimposed on the camera view image. The processor can execute software instructions that allow the client to identify the area of interest and then display the 3D scanner data corresponding to that area of interest. The processor can provide the client with further images identifying the stages in the backfill operation, as shown in the images ofFIG. 5. The initial image can show the baseline for a fill height calculation, namely the existing compacted base on which a new layer of backfill is to be added. The second image in the sequence shows the graded height of the loose fill with the depth calculation obtained by comparing the 3D height of the compacted base with the 3D scanned height of the loose fill. The difference is the depth which can be displayed with the loose fill image. The third image shows the fill depth after compaction, generated by comparing the 3D scanned height of the compacted fill to the baseline 3D height of the compacted base. These images provide an immediate visual representation of the backfill operation at a particular location within the job site.

FIG. 6shows another collection of images that can be generated from the 3D scanner data and camera image data. In these images the entire job site is shown with particular areas of interest identified and labeled and then correlated to the digital image stored in the Cloud. The stored digital image can provide a graphic representation of fill height throughout the job site, including at the three identified areas to provide an immediate visual indication of any problem areas. In this particular image inFIG. 6, the backfill associated with the region labeled “222” can be colored in shades of red representing deviation from the backfill specifications.

The construction site monitoring system of the present disclosure contemplates a network of multiple job sites being monitored by a particular client. In the example ofFIG. 7, three job sites are being remotely monitored by a DOT inspector and by a site foreman via their respective mobile devices. The mobile devices implement an app that allows them to view the data generated by the processor22and stored in the “Cloud”. A third client can access the Cloud-based data from a fixed station at a DOT monitoring center where specific quality assurance and inspection reports can be generated. The mobile app and the fixed location computer can operate a multi-site dashboard that provides the client with immediate and comprehensive access to the data generated by the subsystem10at each of the networked job sites. Thus, inFIG. 8a first page of the dashboard can be a map showing the location of the networked job sites. This dashboard page can display a quality figure indicative of the ratio of out-of-spec backfill operations to in-spec operations. Any of the monitored job sites can be selected for more detailed review in a CSMS Site dashboard shown inFIG. 9. This dashboard page provides data summaries of the backfill activity in the graph at the lower left and a quality overview in the grid map in the lower right. The “Activity Overview” shows the backfill height as it progress over the construction process. The oscillations represent the addition of loose fill followed by compaction, followed by the addition of more loose fill, etc., until the final compaction is completed. Uniform peaks and valleys are generally indicative of good backfill practices. In the example shown inFIG. 9, the backfills occurring between 6 am on February 21 and 6 am on February 22 appear to have a substandard loose fill height and possibly inadequate compaction. The “Quality Grid Overview” chart provides a clear indication of the substandard fill locations within the job site. The data is summarized in the upper left of the Site Dashboard, where it can be seen that the total volume of backfill added to the job site is displayed, which can provide another measure of the overall quality of the backfill operation.

The processor22of the subsystem10is also configured to generate alerts that can be transmitted as a cellular text transmission to the portable devices of the clients. The processor is continuously monitoring the job site and comparing the detected fill data to the specifications. Any deviation from spec results in the generation of an alert providing the details of the alert condition. In the example inFIG. 10, the alert indicates that the lift height or the height of the loose fill immediately prior to compaction exceeded the threshold by a significant amount. Upon receipt of this alert, the client can immediately contact the site supervisor to require remediation, usually in the form of removing and redepositing the loose fill.

The job site monitoring system of the present disclosure allows a client to access archived or logged data over the entire course of the construction work at the job site, as shown in the dashboard screen depicted inFIG. 11.

The construction site monitoring system disclosed herein has several capabilities.

Measure change in height over a specified area of fill dirt behind MSE walls, compare to applicable standards and notify clients, inspectors or stakeholders of noncompliance. Each MSE wall case is identified and monitored independently. The associated area of backfill measured behind each wall would be the width of the wall case multiplied by the known strip length at the current height of the wall. The average height of this area is measured by the 3D scanner and compared to the standard. If the change in height from one compaction event to the next is outside the standard, plus a given tolerance, then the system will automatically notify the stakeholders of this noncompliance and provide an image with the area of interest outlined and named. This insures backfill is dense enough to correctly support the road above and provides the MSE Wall System enough weight and consequently enough friction force on the MSE wall straps to keep the wall panels plum.

Measures angle of walls and individual panels and notifies stakeholders if wall is off plum.

3) Volume of Fill Dirt Loads

Calculates the volume of fill dirt loads received and compares the calculated value to quantity ordered and notify stakeholders of discrepancies in quantities.

4) Quality/Consistency of Fill Dirt

Ability to determine quality of fill dirt by using ranges of reflectivity to identify different materials. If the mix of fill dirt is relatively consistent, then the sensor15should sense a smaller range of reflectivity than it would if the fill dirt contains a larger mix of materials (ex. large amounts of concrete, stone, etc.). The processor22can thus be configured to evaluate the data points based on reflectivity standards for the backfill material specifications.

The integrated GPS data allows the client to overlay the scanner position on a map and have the stakeholders tap into any scanner at any jobsite at any time. The software and the processor22may be configured to permit remote activation of a scan in cases where the subsystem10is not always operating.

Each time the system scans the jobsite it takes generates a point cloud data set or 3D model of the job site and sends it to a common server. Data from multiple scanners at a single job site can be overlaid by an on-site processor22or an off-site processor to compile a complete 3D snapshot of the jobsite. Each 3D snapshot can be used as a “frame” in an animation to show the progression of construction over time.

7) Off the Grid

The site monitoring system's low power consumption will allow it to be powered by solar energy.

8) Target Identification

The scanner15and processor22can be capable of importing object parameters indicative of the physical configuration of the object, such as an MSE Panel, MSE Strap, Rebar, Semi Truck, Dump Truck, Construction Workers, etc. The subsystem can compare point cloud data to “identify” objects within the field of view. The identified objects could be counted and associated with the time stamped scan. This allows the client to monitor delivery quantities and timing, workers and worker placement. This should be relatively easy to accomplish because of the accuracy of the 3D laser and consistency of objects seen at the jobsite.

9) Target Tracking

Target tracking can be achieved if the 3D scanner is continuously scanning.

An augmented reality application could compare previously generated 3D CAD drawings of the planned finished project or of different phases of the project and compare the data to point cloud data collected by the 3D scanner15and processor22. The client can then walk through the jobsite and “view” the conformance to the design. This also allows the user/users to accurately visualize/measure the conformance of the work at different phases of the project as a 3D model in the field rather than looking at multiple 2D plan views.

An augmented reality application could incorporate 3D CAD drawings of the planned finished project and overlay the 3D model to the point cloud data collected by the 3D scanner. The user could then walk through the jobsite with any GPS/camera enabled device and “view” finished design over the image taken in by their camera. This allows the user to identify obstructions/complications which might have been overlooked before construction begins, avoiding costly delays. This also allows the user to accurately Visualize/measure the end product as a 3D model in the field rather than looking at multiple 2D plan views. The construction site monitoring system includes x core components.

The construction site monitoring system disclosed herein is a versatile system designed to monitor all types of construction, including but not limited to: commercial/residential/industrial building construction; highways, ramps and bridges; and agricultural. The system measures all parameters of the jobsite, at every stage, and compares dimensions to known construction plans. Below is a list of steps outlining the sequence of events that would take place on a sample job site using the monitoring system disclosed herein.

Taking the dimensions of the final construction build in mind, the system operator finds a vantage point for the system to provide a desirable reflectivity operating range with minimal blind spots. Multiple scanners may be installed as needed to avoid blind spots, with the scanners15installed at different vantage points. The multiple scanners communicate with a common processor and the processor executes software adapted to combine and correlate the data from each of the scanners to form a complete 3D rendition of the entire job site.

The newly installed system is tested by and an initial scan is conducted to provide baseline point cloud data of the job site before construction begins for future comparison. The cloud data includes the global location of the job site monitoring system and each subsystem so that subsequent clients can access a specific system or subsystem from multiple systems being monitored.

A CAD Model of the completed job or completed job phase can be overlaid on the initial scan to provide future locations and dimensions of all parameters of the jobsite.

From the overlaid model, all objects are identified by the system into individual zones/stations. These zones/stations are individually named and organized in a method familiar to the contractor in a catalog with each individual objects dimensions and location

Tolerances and specifications for each object in the catalog are set.

Applicable standards are uploaded to the processor and attached to associated objects in the catalog for reference.

Scheduled scans are set for beginning and end of every day. This is to make sure regular scans will always capture progress on the jobsite if there are communication/service issues between the contractor and the system.

The contractor is instructed to log in to the system with a phone/tablet. The contractor is provided with a unique username and password and granted limited access to the system scanner controls. The contractor is also allowed access to the catalog, plan views, and applicable standards for reference.

The contractor is instructed to initiate an additional scan before and after each step of the process.

When the contractor initiates this additional scan, they will select which object in the plans they are about to work on out of the catalog of objects—for instance a particular leg of an MSE wall construction. This allows the system to easily monitor multiple processes and associate beginning/end scans of multiple objects by the unique object/process name selected by the contractor.

Each time the system scans the jobsite it creates and records a point cloud data set and panoramic picture.

Any change in the specified zones, outside the tolerance set, triggers a message to stakeholders, identifying which zones are outside of the tolerance and by how much. This message will also include the panoramic picture with the zone highlighted and the associated change in height.

All scan data is saved on the onsite computer hard drive and uploaded to a shared network to be viewed remotely. Different levels of access are granted to different stakeholders. For example, contractors are not allowed to cancel beginning/end of day scans, or control any scanner settings.

At the end of the project, all data sets and panoramic pictures are compiled and presented in the order they were received. This will show the progress over time on the jobsite, identifying each time an object/process was constructed/altered and prove the contractor followed applicable standards and the end result meets specification.

The present disclosure should be considered as illustrative and not restrictive in character. It is understood that only certain embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the disclosure are desired to be protected.