# Patent

## Title
Systems and methods for assessing a roof and generating models

## Abstract

A damage assessment module operating on a computer system generating a model undamaged roof shingle includes using a method based on the average nearest-neighbor distance. The damage assessment module identifies a set of points comprising a first point cloud representing a first shingle and a set of points from a second point cloud representing a second shingle. The damage assessment module then calculates an average nearest-neighbor distance for the set of points. Based on the average, the damage assessment module calculates a threshold distance. The damage assessment module then stores the set of points to memory as a point cloud representing a model roof shingle that can be later retrieved and compared to point clouds of individual shingles. The damage assessment module improves the consistency and accuracy associated with assessment of the roof and eliminates the need for the estimator to use subjective assessment results, which can be inadequate.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 14/047,873, filed Oct. 7, 2013, which claims priority to U.S. Provisional Application No. 61/799,452 filed Mar. 15, 2013, which are hereby incorporated by reference for all purposes.


FIELD OF THE DISCLOSURE
This disclosure relates to systems and methods for assessing roof damage for insurance companies.
BACKGROUND
Insurance companies spend considerable amounts of resources estimating damage caused to shingles. Currently an estimator needs to be on site to determine whether or not a roof needs to be replaced. Generally, the estimator uses a subjective assessment of the roof. Unfortunately, subjective assessments generally do not provide a repeatable or consistent approach, resulting in inconsistent and unreliable results. For example, once on the roof, different lighting conditions and shingle types may make it very difficult, even for an experienced estimator, to assess the amount of damage to a roof.
In addition to providing inadequate results, a subjective assessment may expose the estimator to dangerous conditions. For example, the estimator exposes himself or herself to the risk of falling. Windy or rainy conditions, which are common in many locales, enhance this risk.
SUMMARY
A system and method for estimating roof damage provides an analytical approach that is repeatable and consistent, regardless of who is doing the estimation. The systems and methods may be automated, removing the subjectivity of a person doing the estimation and helping new and inexperienced estimators produce consistent results regardless of the level of training and experience.
A system and method for generating a model of an undamaged roof shingle includes causing a processor to identify a set of points, the set comprising points from a first point cloud representing a first shingle and points from a second point cloud representing a second shingle. The system and method further includes causing a processor to calculate an average nearest-neighbor distance for the set. The system and method also includes causing a processor to calculate a threshold distance based on the determined average. The system and method includes causing a processor to store the set to a memory as a point cloud representing a model roof shingle to be later retrieved and compared to point clouds of individual shingles, which may be used in estimating damage to at least part of the roof.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a block diagram of an example system including a computer system for evaluating a roof of a structure in accordance with the described embodiments.
FIG. 2 illustrates a block diagram of an example computer system on which a method for evaluating a roof may operate in accordance with the described embodiments.
FIG. 3 illustrates an example point cloud of a structure and an example point cloud of a roof in accordance with the described embodiments.
FIG. 4 illustrates an example method for estimating damage to a roof in accordance with the described embodiments.
FIG. 5 illustrates a method for identifying individual shingles on a roof in accordance with the described embodiments.
FIG. 6 illustrates an example method for generating a point cloud representing a model shingle in accordance with the described embodiments.
FIG. 7 illustrates an example method for estimating damage to a roof in accordance with the described embodiments.



DETAILED DESCRIPTION
A damage assessment module operating on a computer system automatically evaluates a roof, estimating damage to the roof by analyzing a point cloud. Based on the analysis, the damage assessment module generates a report on the roof damage. The report may be used to determine the financial cost of the damage and/or determine whether the roof should be replaced or repaired. The damage assessment module eliminates the need for an estimator to physically climb onto a roof for evaluation purposes. Moreover, the damage assessment module completely eliminates the need for a human estimator to travel to the physical site where the roof is located. The damage assessment module also improves the consistency and accuracy associated with estimating damage to a roof. While environmental factors, such as poor lighting, can negatively affect the consistency and reliability of current damage estimation techniques, the damage assessment module greatly reduces the significance of such factors. Because the damage assessment module relies on an objective analysis of a detailed point cloud rather than a subjective opinion of a human estimator relying on a visual inspection of the roof, the damage assessment module enables a high level of consistency and reliability with regard to estimating damage to roofs. Finally, due to the automated nature of the damage assessment module and the objective analysis implemented by the damage assessment module, human estimators will be capable of using the damage assessment module to produce high quality results, regardless of the level of training or experience.
System Overview
FIG. 1 illustrates a block diagram of an example system 100 including a computer system 200 for evaluating a roof 115 of a structure 110 in accordance with the described embodiments. The roof 115 includes potential areas of damage 122, 124, and 126.
The example system 100 includes a 3D scanner configured to scan an object and generate a point cloud. The 3D scanner 130 may implement any of a number of techniques to scan an object, including, for example, time-of-flight techniques or triangulation techniques. The 3D scanner 130 may implement systems utilizing laser, white light, audio, infrared, or any other technology suitable for scanning the roof 115.
In operation, the 3D scanner 130 generates a point cloud based on a scan of the roof 115 and transmits the point cloud via a network 140. The computer system 200 receives the point cloud via the network 140, storing the point cloud to memory. The computer system 200 then estimates damage to the roof 115 by analyzing the point cloud. For example, the computer system may identify points corresponding to the damaged areas 122, 124, and 126. After estimating the location and/or extent of damage to the roof 115, the computer system 200 may generate a report of the damage.
In some embodiments, the computer system 200 may receive the point cloud from another device or system. For example, the computer system 200 may receive the point cloud from a computer system such as a server. The computer system 200 may also receive the point cloud from a storage device connected to the computer system 200 (such as a USB device or an SD card, for example).
FIG. 2 illustrates a block diagram of an example computer system 200 on which a method for evaluating a roof may operate in accordance with the described embodiments. The computer system 200 may take the form of any general purpose or special purpose computer or computing device. For example, the computer system 200 may be a personal computer, server, laptop, tablet, a set-top box, a multiprocessor system, a microprocessor system, or any other type of computer. Further, the computer system 200 may be a distributed computing environment including multiple computing devices.
The computer system 200 includes one or more processors 205, a computer-readable memory 210, a network interface 215, a user interface 220, and a system bus 250. The processor 205 communicates with the other components of the computer 200 via the system bus 250. The processor 205 is configured to fetch and execute instructions stored at the memory 210.
The network interface 215 is configured to establish communication via a network and may include an antenna, a port for wired connection, a connection to a modem, a connection to a router, or some combination thereof. The User Interface (UI) 210 includes a display 262 and an input device 264 in this example. Generally speaking, the UI 210 may include any suitable input or output devices, such as a touchscreen, a keyboard, a mouse and/or speakers. In some embodiments, some or all of the UI 210 may be remotely located relative to the other components of the computer system 200 and the UI 210 may communicate with the components of the computer system 200 via the network interface 215.
The memory 210 is configured to store data, including instruction sets making up one or more services or programs and any data operated on or produced by such services or programs. The memory 210 may include volatile (e.g., RAM) and/or non-volatile memory (e.g., a harddisk) and may be removable or non-removable memory. More particularly, the memory 210 includes point cloud data 252, a damage assessment module 254, and report data 256. The point cloud data 252 includes one or more point clouds representing a surface of a structure, roof and/or shingle, each point cloud being a set of data points in a three-dimensional coordinate system. The point cloud data 252 may include point clouds used as input for the damage assessment module 254, as well as point clouds generated or modified by the damage assessment module 254. Each data point in a point cloud corresponds to a particular point on the surface of the structure/roof/shingle. As discussed further below, the damage assessment module 254 is a program for estimating damage to a roof. The report data 256 is generated in response to the estimation performed by the damage assessment module 254. The report data may be produced by the damage assessment module 254 or by a reporting module (not shown).
The processor 205 may perform the methods or operations described herein. In some instances, performance of certain parts of the methods or operations described herein may be distributed among one or more processors residing across a plurality of machines. The one or more processors may share a similar geographic location in some instances (e.g., a server farm), or may be distributed across a number of geographically distinct areas. Moreover, the one or more processors may operate to support performance of relevant operations in a “cloud computing” environment. For example, at least some of the operations may be performed by a group of computers or by the previously described plurality of machines, wherein the operations are accessible via a network (accessible by, e.g., the network interface 215).
In operation, the computer system 200 receives point cloud data at the network interface 215 (via, e.g., the network 140 shown in FIG. 1). Alternatively, the point cloud data 252 may be received at the UI 210 or at a peripheral device interface (not shown), such as a Universal Serial Bus (USB) interface. In any event, the received point cloud data is stored as at least part of the point cloud data 252 at the memory 210. Any type of communication protocol may be implemented at the computer system 200 for receiving the point cloud data. For example, in some embodiments the computer system 200 receives the point cloud data 252 via a transfer initiated by another system, while in other embodiments the computer system 200 requests the point cloud data 252 from another system, resulting in the other system transferring the point cloud data 252 to the computer system 200.
In further operation, the processor 205 executes the damage assessment module 254 to estimate damage to a roof by analyzing a point cloud representing the roof or a structure with the roof. As discussed in further detail below, estimating damage to the roof may include: (i) identifying individual shingles (i.e., segmenting shingles) within the point cloud, (ii) identifying points of potential damage to each of the shingles, and (iii) determining which areas of the roof are damaged based on the identified points of potential damage to the shingles.
Finally, the computer system 200 may generate a report of the estimated damage to the roof and save the report to the memory 210 as at least part of the report data 256. The report may include information pertaining to the location of the damaged areas on the roof, as well as the extent of damage to the roof. The report may be a file or data set including information pertaining to some or all of the estimated damage to the roof. Furthermore, the report may enable various textual or graphical representations of the estimated damage to be generated (e.g., images, video, diagrams, charts, text, etc.). For example, in some embodiments an output may be provided at the display 262 (such as a television or computer monitor) based on the report. In other instances, a printer (not shown) may print one or more documents based on the report. The printer may be connected to a peripheral device interface at the computer system 200 (not shown), or may be in network communication with the computer system 200 via the network interface 215. In still other instances, the report may be saved as a file and transferred to another system (via, e.g., the network interface 215).
FIG. 3 illustrates an example point cloud 310 of the structure 110 and an example point cloud 315 of the roof 115 in accordance with the described embodiments. The point cloud 310 includes areas 322a, 324a, and 326a of potential damage. The point cloud 315 includes areas 322b, 324b, and 326b of potential damage.
The point cloud 310 may be received and stored at a computer system (such as the computer system 200 shown in FIG. 2). The computer system may identify the points from the point cloud 310 corresponding to the roof 115 by identifying features associated with the roof 115. For example, shingles, which are typically only found on a roof, generally have a distinct shape and pattern in comparison to the rest of a structure. Thus, the computer system may identify points corresponding to shingles on the roof 115 based on the shapes of the shingles. The computer system may then generate the point cloud 315 based on the identified points. In some embodiments, the computer system may receive the point cloud 315 from a second system rather than generating the point cloud 315 from the point cloud 310. For example, the computer system may receive the point cloud 315 from a 3D scanner, a second computer device, a network device on a network, etc.
As discussed further below, the computer system may identify one or more individual shingles represented in the point cloud 315. In some instances, the computer system may generate a point cloud corresponding to each shingle (shingle point cloud). The shingle point clouds may be analyzed to identify points representing potential areas of damage to the shingle. In some instances, points identified as potential damage may then be mapped to a point cloud representing the roof or structure associated with the shingles (such as the original point cloud from which the shingle point clouds were identified). Using the points identified as potential damage, the computer system may identify groups or clusters of potential damage to identify areas on the roof having physical features consistent with roof damage.
Example Methods for Estimating Damage to a Roof Based on a Point Cloud
FIG. 4 illustrates an example method 400 for estimating damage to a roof in accordance with the described embodiments. The method 400 may be implemented, in whole or in part, on one or more devices or systems such as the computer system 200 of FIG. 2. The method 400 may be saved as a set of instructions, routines, programs, or modules on memory such as the memory 210 shown in FIG. 2. In particular, the method 400 may be saved as at least part of the damage assessment module 254 shown in FIG. 2. In particular, the method 400 may be saved as at least part of the damage assessment module 254 shown in FIG. 2.
The method 400 begins when a computer system generates, based on a point cloud of a roof (roof point cloud), point clouds representing individual shingles (shingle point cloud) (block 405). By identifying individual shingles (i.e., shingle segmentation) on the roof, the computer system may identify areas of potential damage to individual shingles, allowing the computer system to estimate damage to the roof as a whole. Identifying damage to particular shingles may be simpler than identifying damage to the roof as a whole because shingles tend to have consistent and predictable physical characteristics, such as shape and size. Consequently, as described below, shingles may offer the benefit of having a reliable reference model to which they may be compared.
After generating the shingle point clouds, the computer system detects which points in each of the shingle point clouds, if any, represent points of potential damage to the shingles (damaged points) (block 410). In typical embodiments, the computer system detects damaged points by comparing each of the shingle point clouds to a model point cloud. The model point cloud generally represents an undamaged shingle, though it may have characteristics consistent with normal wear and tear. Thus, for example, the shingle cloud may be superimposed on the model point cloud and points corresponding to undamaged areas of the shingle will be near one or more points in the model point cloud. Points corresponding to damaged areas of the shingle, on the other hand, will tend to be further away from points in the model point cloud. Consequently, outlier points in each of the shingle point clouds may be identified as damaged points.
After detecting the damaged points by comparing the shingle point clouds to a model point cloud, the computer system may map the damaged points to the roof point cloud and identify clusters of damaged points to estimate which areas of the roof are damaged (block 415). In some embodiments, the computer system determines which, if any, of the identified clusters represent a false positive. The computer system may also, in certain circumstances, identify an extent or severity of the damage associated with each cluster.
FIG. 5 illustrates a method 500 for identifying individual shingles on a roof in accordance with the described embodiments. The method 500 may be implemented, in whole or in part, on one or more devices or systems such as the computer system 200 of FIG. 2. The method 500 may be saved as a set of instructions, routines, programs, or modules on memory such as the memory 210 of FIG. 2. In particular, the method 500 may be saved as at least part of the damage assessment module 254 shown in FIG. 2.
The method 500 begins when a computer system identifies a first point from a point cloud representing a roof (block 505). The computer system adds the first point to a set (block 510). The computer system then calculates a first measurement of the surface shape of the set (block 515). The computer system adds a second (unevaluated) point (i.e., a point not previously added to the set) to the set (block 520) and determines a second measurement of the surface shape of the set (block 525). When the difference between the first and second measurement exceeds a threshold, the second point is removed from the set (block 530).
The computer system may determine whether there are unevaluated points in the point cloud (block 535). If there are points the computer system has not evaluated for adding to the set, the computer system may implement blocks 515-535 with regard to the unevaluated points. If there are no more points to evaluate, the computer system may store the set as a point cloud representing a shingle (block 540). In some instances, the method 500 may be implemented multiple times to identify multiple objects from the point cloud representing the property
FIG. 6 illustrates an example method 600 for generating a point cloud representing a model shingle in accordance with the described embodiments. The method 600 may be implemented, in whole or in part, on one or more devices or systems such as the computer system 200 of FIG. 2. The method 600 may be saved as a set of instructions, routines, programs, or modules on memory such as the memory 210 of FIG. 2. In particular, the method 600 may be saved as at least part of the damage assessment module 254 shown in FIG. 2.
The method 600 begins when a computer system generates a point cloud representing two or more shingles (aggregate point cloud) (block 605). The computer system aligns the shingle point clouds in a normalized coordinate system. The shingle point clouds are aligned at one or more reference points, such as along a center point associated with each of the shingle point clouds. The resulting aggregate point cloud includes points from each of the two or more shingle point clouds.
Next, the computer system may select a set of points (block 610). The set of points may be selected by sampling the aggregate point cloud. Alternatively, the set of points may include all of the points from the aggregate point cloud.
The computer system may then determine the mean nearest-neighbor distance for the set of points (block 615). The computer system may also calculate the standard deviation of the squared Euclidean distance of all the points in the set.
The computer system may calculate a threshold based on the mean nearest-neighbor distance for the set of points (block 620). For example, the threshold may be calculated as a scaled number of standard deviations away from the mean. The computer system may save the set of points to a memory as a model point cloud (block 630). After the model point cloud has been created, the shingle point clouds may be compared to the model point cloud. Each point from the model point cloud may be compared, point-by-point, to each of the points in the shingle point clouds. If any point in the model point cloud is farther away from its nearest-neighbor in the shingle point cloud than the predetermined threshold, the point in the model point cloud may be marked as potentially damaged. The points marked as potentially damaged may be mapped back to the original roof or structure point cloud.
FIG. 7 illustrates an example method 700 for estimating damage to a roof in accordance with the described embodiments. The method 700 may be implemented, in whole or in part, on one or more devices or systems such as the computer system 200 of FIG. 2. The method 700 may be saved as a set of instructions, routines, programs, or modules on memory such as the memory 210 of FIG. 2. In particular, the method 700 may be saved as at least part of the damage assessment module 254 shown in FIG. 2.
The method 700 begins when a computer system identifies individual shingles from a point cloud representing a roof or a structure with a roof (i.e., the computer system segments the point cloud into single shingle segments) (block 705). This may include generating shingle point clouds corresponding to each shingle. While some embodiments implement region growing segmentation, the computer system may implement any segmentation method (such as planar segmentation or difference of normals segmentation, for example). Region growing starts by adding a single point or small group of points to a set. Then, the curvature and/or smoothness of the set is calculated. If the smoothness or curvature goes over a specified value, the computer system may remove the added point or small group from the set. This process may occur in an iterative manner, with the computer system adding and removing points depending on how the shape of the set is affected. Eventually, the cluster of points remaining in the set after being added and evaluated represent a single segment or shingle.
The computer system may align all of the segmented shingles to a common alignment (block 710). Alignment may include rotating and translating the roof point cloud so that its centroid is located at an origin point of a 3D coordinate system and the roof's surface normal is aligned to the z-axis of the 3D coordinate system. The computer system may utilize a number of methods for alignment, including a normal alignment method and an iterative closest point method. Alignment may additionally or alternatively include aligning each of the shingle point clouds. The normal based alignment method causes the computer system to identify the median or average normal of each shingle point cloud. The computer system may then align the centroid of each shingle point cloud to (0,0,0) and align the median normal of each shingle point cloud to the vector facing (0,0,1). In other embodiments, the computer system may use the iterative closest point (ICP) method during alignment.
In some instances, the computer system may identify clusters (i.e., groups) of shingle point clouds (block 715). One of ordinary skill in the art will appreciate that numerous clustering methods may be implemented to identify such clusters or groups, any one of which may be implemented in accordance with block 715. Accordingly, the subsequently described examples serve illustrative purposes only and are non-limiting in nature. For example, the shingle point clouds may be grouped by size and/or shape. The computer system may implement clustering methods such as the k-medoids method to separate the shingles into separate groups. In implementing such a method, selecting the initial cluster centers may be performed by selecting the first medoid uniformly at random. A medoid may be a point in a shingle point cloud whose average dissimilarity to all the points in the shingle point cloud is minimal. In some instances, the medoid of a shingle point cloud is the most centrally located point in the shingle point cloud. The computer system may calculate the difference in the dimensions of the bounding box that encloses the first medoid. The computer system may select the next medoids based on the shingle point clouds that have the largest variance between the initial medoid. This may result in an initial set of medoids that are already separated into bins by their shape and only require a few iterations to converge. In some embodiments, the computer system may implement a k-means method for identifying clusters of shingle point clouds using the “model shingle” as a mean.
The computer system may then detect points corresponding to potentially damaged sections of each shingle (i.e., damage extraction) (block 720). In order to detect said points, a model shingle point cloud representing an undamaged shingle may be created (model). In some instances, the model represents an average of all of the scanned shingles on the roof. While damage will vary from shingle to shingle, normal wear and tear will generally be consistent across all shingles. Thus, the significance of most shingle damage will be negligible when creating the model, while wear and tear consistent across the majority of the shingles will generally be accounted for in the model. As discussed in further detail below, the model may be compared to each of the shingle point clouds by comparing the coordinate positions of the points in the model to the coordinate positions of the points in each of the shingle point clouds. Any outlier points in the shingle point clouds (i.e., any point with a nearest-neighbor point in the model shingle that exceeds a certain threshold) may be identified as damaged points or potentially damaged points (damaged points). The damaged points may be mapped to a point cloud, and in particular, to the original roof point cloud.
In some embodiments, creating a model shingle point cloud may comprise transforming the shingle point clouds so that the shingles share a common alignment. In one embodiment, the transformation may be implemented using an iterative closest point (ICP) method. The computer system may manipulate two shingle point clouds at a time, continually transforming the two shingle point clouds until either the sum of the distances between the points is lower than a given threshold, or a maximum number of iterations is reached. This ICP method may be implemented with regard to some or all of the shingle point clouds to give the shingle point clouds a common alignment.
The computer system may filter the resulting points using, for example, a voxel grid down sampling of the points. A voxel grid down sampling may create boxes of a specified width and all the points that lie inside one box may be reduced down to their centroid. The computer system may then automatically select a classification threshold for each shingle point cloud by iterating through each of the shingle point clouds and selecting points at random. The computer system may obtain each point's k nearest-neighbors in the model and compute the mean and/or standard deviation of the squared Euclidean distances over the points. The threshold of a shingle point cloud may be selected based on a scaled number of standard deviations away from the mean, where the scaled value is a parameter.
After generating one or more models and/or identifying thresholds for shingle point clouds, the computer system may identify points of potential damage within the shingle point clouds by comparing, point-by-point, one or more points from the model(s) to one or more points from the shingle point cloud(s). In some embodiments, when any point in the model is farther than the specified threshold away from its nearest-neighbor in the shingle point cloud, the point in the model may be marked as damage or potential damage. The computer system may take the points marked as damage in the model point cloud and map them back to points in the original dataset (i.e., the roof point cloud). This mapping back to the original dataset may be advantageous because the points in the model may not represent real points in the shingle. Further, mapping the points to the shingle point cloud may result in losing points along the edge, or may result in damaged segments that may not be included in the shingle point cloud. A method is briefly outlined below (this does not include transforming the clouds to new coordinate frames for comparison):















For each region in regionGrownClouds:









For each point in model:









neighbor = region.nearestNeighborTo(point)



distance = neighbor.getDistanceTo(point)



If (distance > threshold):









damagePoints.add(point)









For each point in damagePoints:









neighbor = dataset.nearestNeighborTo(point)



damagePoints.add(point)









return damagePoints










After detecting damaged points for each shingle, the computer system may segment the damaged points into clusters of points that may be considered a single cluster of damage (i.e., damage segmentation) (block 725). While an isolated single damage point is unlikely to represent a significant physical feature (it may represent a measurement error, for example) and thus unlikely to represent an area of damage to be concerned about, a cluster of damaged points likely represents physical features consistent with a damaged area. Damage segmentation may enable the computer system to use the clusters for classification training. Damage segmentation may be carried out by the computer system using methods such as Euclidean clustering.
Once clusters of damage have been identified, the computer system may reduce the effects of noise in the shingle point clouds by identifying false positives (i.e., clusters that were likely misidentified as damaged regions). The computer system may implement classification methods to identify areas that were wrongly identified as damaged areas. For example, areas near shingle edges may sometimes be wrongly identified as damaged. This may be due to the fact that areas between shingles tend to have more variation in shape and position, making it difficult to identify a baseline for determining whether an area near or on the shingle edge is damaged. Learning models, such as support vector machines (SVM), that recognize patterns may be used to identify false positives.
Additional Considerations
The following additional considerations apply to the foregoing discussion. In some embodiments, the disclosed methods and systems may store, at a database, manually classified damage regions (i.e., classified by a user or estimator as, e.g., hail damage, not damage, fraud, etc.). The systems and methods may rely on the classified regions to help classify new damaged regions.
In some embodiments, the disclosed methods and systems may be used to determine a roof needs to be replaced based on the amount of damage showing on the roof, using the size and number of dents. Furthermore, the disclosed methods and systems may utilize models that account for different types of roof material, shingle size, and amount of wear already on the roof. Each of these roof parameters may be stored at a database and used to increase the accuracy of roof models.
Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein.
Certain implementations are described herein as including logic or a number of components, modules, or mechanisms. Modules may constitute either software modules (e.g., code implemented on a tangible, non-transitory machine-readable medium such as RAM, ROM, flash memory of a computer, hard disk drive, optical disk drive, tape drive, etc.) or hardware modules (e.g., an integrated circuit, an application-specific integrated circuit (ASIC), a field programmable logic array (FPLA)/field-programmable gate array (FPGA), etc.). A hardware module is a tangible unit capable of performing certain operations and may be configured or arranged in a certain manner. In example implementations, one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware modules of a computer system (e.g., a processor or a group of processors) may be configured by software (e.g., an application or application portion) as a hardware module that operates to perform certain operations as described herein.
Unless specifically stated otherwise, discussions herein using words such as “processing,” “computing,” “calculating,” “determining,” “presenting,” “displaying,” or the like may refer to actions or processes of a machine (e.g., a computer) that manipulates or transforms data represented as physical (e.g., electronic, magnetic, or optical) quantities within one or more memories (e.g., volatile memory, non-volatile memory, or a combination thereof), registers, or other machine components that receive, store, transmit, or display information.
As used herein any reference to “one implementation,” “one embodiment,” “an implementation,” or “an embodiment” means that a particular element, feature, structure, or characteristic described in connection with the implementation is included in at least one implementation. The appearances of the phrase “in one implementation” or “in one embodiment” in various places in the specification are not necessarily all referring to the same implementation.
Some implementations may be described using the expression “coupled” along with its derivatives. For example, some implementations may be described using the term “coupled” to indicate that two or more elements are in direct physical or electrical contact. The term “coupled,” however, may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. The implementations are not limited in this context.
As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
In addition, use of the “a” or “an” are employed to describe elements and components of the implementations herein. This is done merely for convenience and to give a general sense of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.
Upon reading this disclosure, those of skill in the art will appreciate still additional alternative structural and functional designs for a system and a process for inspecting a structure to estimate the condition of a structure through the disclosed principles herein. Thus, while particular implementations and applications have been illustrated and described, it is to be understood that the disclosed implementations are not limited to the precise construction and components disclosed herein. Various modifications, changes and variations, which will be apparent to those skilled in the art, may be made in the arrangement, operation and details of the method and apparatus disclosed herein without departing from the spirit and scope defined in the appended claims.

## Claims

1. A computer system for generating a model roof shingle, the computer system comprising:
one or more processors; and
one or more memories coupled to the one or more processors, the one or more memories including non-transitory computer readable instructions that, when executed at the one or more processors, cause the one or more processors to:
(A) identify, from one or more scans of one or more roofs including a first shingle and a second shingle, a first point cloud representing the first shingle and a second point cloud representing the second shingle;
(B) generate a model point cloud representing a model roof shingle based on the one or more scans of the one or more roofs, the generated model point cloud including a set of points, the set of points including points from the first point cloud representing the first shingle and points from the second point cloud representing the second shingle;
(C) generate one or more metrics for the model point cloud, the generated one or more metrics for the model point cloud including:
(i) an average nearest-neighbor distance calculated by the one or more processors for the set of points in the model point cloud, and
(ii) a threshold distance calculated by the one or more processors based on the calculated average nearest-neighbor distance for the set of points in the model point cloud, wherein the threshold distance represents a maximum nearest-neighbor distance metric o be used in determining whether a particular point is considered to be potentially damaged;

(D) store the model point cloud to one of the one or more memories;
(E) generate a report for a damage estimate generated based on a comparison between the model point cloud and a comparison point cloud representing a shingle, the generated report including a textual or graphical representation of the damage estimate;
wherein when the model point cloud is compared to the comparison point cloud:
(i) a nearest-neighbor distance is determined for a plurality of points within the comparison point cloud; and
(ii) when a point from the plurality of points within the comparison point cloud is determined to have a nearest-neighbor distance exceeding the calculated threshold distance, the point is marked as potentially damaged; and

wherein the comparison point cloud is one of the following: the first point cloud representing the first shingle, the second point cloud representing the second shingle, or a third point cloud representing a third shingle.

2. The system of claim 1, wherein the calculated average nearest-neighbor distance corresponds to distances between points within the set of points, wherein the non-transitory computer readable instructions that cause the one or more processors to calculate the average nearest-neighbor distance for the set of points further comprise instructions that cause the one or more processors to:
identify a first point in the set of points and a first distance measurement, the first distance measurement being a distance between the first point and a point within the set of points that is nearest to the first point relative to other points within the set of points;
identify a second point in the set of points and a second distance measurement, the second distance measurement being a distance between the second point and a point within the set of points that is nearest to the second point relative to other points within the set of points; and
calculate the average nearest-neighbor distance based, at least in part, on the identified first distance measurement and the identified second distance measurement.

3. The system of claim 2, wherein the one or more memories further comprise non-transitory computer readable instructions that cause the one or more processors to:
identify squared Euclidean distances (i) between the first point in the set of points and the point within the set of points nearest to the first point, and (ii) between the second point in the set of points and the point within the set of points nearest to the second point;
wherein the average nearest-neighbor distance is calculated based, at least in part, on the identified squared Euclidean distances.

4. The system of claim 1, wherein the one or more scans of the one or more roofs were obtained by scanning a single roof including both the first shingle and the second shingle.

5. The system of claim 1, wherein the one or more memories further include non-transitory computer readable instructions that, when executed at the one or more processors, cause the one or more processors to:
after identifying the first point cloud representing the first shingle and the second point cloud representing the second shingle: align the first and second point clouds, wherein the first and second point clouds are aligned at one or more reference points, such as along a center point associated with each of the first and second point clouds.

6. The system of claim 5, wherein aligning the first and second point clouds comprises transforming the first and second point clouds using an iterative closest point (ICP) method so that the first and second point clouds share a common alignment.

7. The system of claim 5, wherein aligning the first and second point clouds comprises manipulating the first and second point clouds by continually transforming the first and second point clouds until either a sum of distances between points in the first and second point clouds is lower than a given threshold, or a maximum number of iterations is reached.

8. The system of claim 1, wherein the non-transitory computer readable instructions that cause the one or more processors to calculate the threshold distance based on the calculated average nearest-neighbor distance for the set of points comprise instructions that cause the one or more processors to:
calculate the threshold distance as a scaled number of standard deviations away from the calculated average nearest-neighbor distance for the set of points;
wherein the system further comprises non-transitory computer readable instructions that, when executed, cause the one or more processors to:
(i) compare a plurality of comparison point clouds each representing a shingle to the model point cloud, wherein each point from the model point cloud may be compared, point-by-point, to each of the points in each of the plurality of comparison point clouds;
(ii) for each of the plurality of comparison point clouds: mark as potentially damaged any point that is farther away from its nearest-neighbor in the model point cloud than the calculated threshold distance; and
(iii) map any points marked as potentially damaged to a point cloud that: (a) represents a roof or structure that includes the first and second shingles, and (b) was the original point cloud from which the first and second points clouds were derived.

9. The system of claim 1, wherein the one or more memories further comprise non-transitory computer readable instructions that cause the one or more processors to:
select a classification threshold for each of the first and second point clouds by iterating through each of the first and second point clouds and selecting points at random:
wherein the set of points is a filtered subset of all of the points included in the first point cloud and the second point cloud.

10. The system of claim 1, wherein the calculated average nearest-neighbor distance corresponds to distances between points from the first point cloud and points from the set of points,
wherein the non-transitory computer readable instructions that cause the one or more processors to calculate the average nearest-neighbor distance for the set of points comprise instructions that cause the one or more processors to:
align the set of points and the first point cloud so that the set of points and the first point cloud share a reference coordinate position;
identify a first point in the set of points and a first distance measurement, the first distance measurement being a distance between the first point and a point within the first point cloud nearest to the first point;
identify a second point in the set of points and a second distance measurement, the second distance measurement being a distance between the second point and a point within the first point cloud nearest to the second point; and
calculate the average nearest-neighbor distance based, at least in part, on the identified first distance measurement and the identified second distance measurement.

11. The system of claim 10, wherein the reference coordinate position is a coordinate position for both:
(i) a point from the set of points; and
(ii) a point from the first point cloud.

12. The system of claim 10, wherein the reference coordinate position is either:
(i) a coordinate position for both a center position identified from the set of points and a center position identified from the first point cloud; or
(b) a coordinate position for both a corner identified from the set of points and a corner identified from the first point cloud.

13. The system of claim 10, wherein the one or more memories further include non-transitory computer readable instructions that, when executed at the one or more processors, cause the one or more processors to:
calculate a second average nearest-neighbor distance for the set of points, the second average-nearest neighbor distance corresponding to distances between points from the second point cloud and points from the set of points; and
calculate a second threshold distance based on the calculated second average nearest-neighbor distance, the second threshold distance particular to the second point cloud.

14. A computer-implemented method for generating a model roof shingle, the method comprising:
(A) identifying, from one or more scans of one or more roofs including a first shingle and a second shingle, a first point cloud representing the first shingle and a second point cloud representing the second shingle;
(B) generating a model point cloud representing a model roof shingle based on the one or more scans of the one or more roofs, the generated model point cloud including a set of points, the set of points including points from the first point cloud representing the first shingle and points from the second point cloud representing the second shingle;
(C) generating one or more metrics for the model point cloud, said generating including:
(i) calculating an average nearest-neighbor distance for the set of points;
(ii) calculating a threshold distance based on the calculated average nearest-neighbor distance for the set of points in the model point cloud, wherein the threshold distance represents a maximum nearest-neighbor distance metric to be used in determining whether a particular point is considered to be potentially damaged;

(D) storing the set of points to one or more memories, as a model point cloud representing the model roof shingle, to be later retrieved and compared to a comparison point cloud representing a shingle;
(E) generating a report for a damage estimate generated based on a comparison between the model point cloud and a comparison point cloud representing a shingle, the report including a textual or graphical representation of the damage estimate;
wherein when the model point cloud is compared to the comparison point cloud:
(i) a nearest-neighbor distance is determined for a plurality of points within the comparison point cloud; and
(ii) when a point from the plurality of points within the comparison point cloud is determined to have a nearest-neighbor distance exceeding the calculated threshold distance, the point is marked as potentially damaged; and

wherein the comparison point cloud is one of the following: the first point cloud representing the first shingle, the second point cloud representing the second shingle, or a third point cloud representing a third shingle.

15. The method of claim 14, wherein calculating the average nearest-neighbor distance for the set of points comprises:
identifying a first point in the set of points and a first distance measurement, the first distance measurement being a distance between the first point and a point within the set of points that is nearest to the first point relative to other points within the set of points;
identifying a second point in the set of points and a second distance measurement, the second distance measurement being a distance between the second point and a point within the set of points that is nearest to the second point relative to other points within the set of points; and
calculating the average nearest-neighbor distance based, at least in part, on the identified first distance measurement and the identified second distance measurement.

16. The method of claim 15, further comprising:
identifying squared Euclidean distances (i) between the first point in the set of points and the point within the set of points nearest to the first point, and (ii) between the second point in the set of points and the point within the set of points nearest to the second point;
wherein the average nearest-neighbor distance is calculated based, at least in part, on the identified squared Euclidean distances.

17. The method of claim 14, further comprising obtaining the one or more scans of the one or more roofs by scanning a single roof including both the first shingle and the second shingle.

18. The method of claim 14, further comprising:
after identifying the first point cloud representing the first shingle and the second point cloud representing the second shingle:
aligning the first and second point clouds, wherein the first and second point clouds are aligned at one or more reference points, such as along a center point associated with each of the first and second point clouds.

19. The method of claim 18, wherein aligning the first and second point clouds comprises transforming the first and second points clouds using an iterative closest point (ICP) method so that the first and second point clouds share a common alignment.

20. The method of claim 18, wherein aligning the first and second point clouds comprises manipulating the first and second point clouds by continually transforming the first and second point clouds until either a sum of distances between points in the first and second point clouds is lower than a given threshold, or a maximum number of iterations is reached.

21. The method of claim 14, wherein calculating the threshold distance based on the calculated average nearest-neighbor distance for the set of points includes:
calculating the threshold distance as a scaled number of standard deviations away from the calculated average nearest-neighbor distance for the set of points;
wherein the method further comprises:
(i) comparing a plurality of comparison point clouds each representing a shingle to the model point cloud, wherein each point from the model point cloud may be compared, point-by-point, to each of the points in each of the plurality of comparison point clouds;
(ii) for each of the plurality of comparison point clouds: marking as potentially damaged any point that is farther away from its nearest-neighbor in the model point cloud than the calculated threshold distance; and
(iii) mapping any points marked as potentially damaged to a point cloud that: (a) represents a roof or structure that includes the first and second shingles, and (b) was the original point cloud from which the first and second points clouds were derived.

22. The method of claim 14, further comprising:
selecting a classification threshold for each of the first and second point clouds by iterating through each of the first and second point clouds and selecting points at random:
wherein the set of points is a filtered subset of all of the points included in the first point cloud and the second point cloud.