Use of the iPhone 13 Pro LiDAR Scanner for Inspection and Measurement in the Mineshaft Sinking Process
Round 1
Reviewer 1 Report (Previous Reviewer 1)
As some contents about mineshaft sinking (volume change) have been added, I have no further comments.
Author Response
Dear Sir/Madam,
Thank You for Your review!
Best regards,
Wojciech Rutkowski
Reviewer 2 Report (New Reviewer)
This article explores the use of the iPhone 13 Pro LiDAR scanner for inspections and measurements in the mineshaft sinking process. The study evaluates the accuracy and usefulness of 3D models created by the scanner at various depths during the construction of the GG-1 ventilation shaft in Kwielice, Poland. The results demonstrate that the iPhone 13 Pro LiDAR scanner is effective for inspections that do not require high levels of accuracy. Additionally, the study highlights a quick and reliable method of volume calculation using open-source software. The manuscript is useful and interesting. Nevertheless, the paper requires to go through a careful revision before publication. I invite the authors to modify their manuscript according to the below comments.
The introduction requires significant improvement as it lacks informativeness. In any piece of writing or research paper, the introduction plays a crucial role in setting the tone, capturing the reader's attention, and providing a clear overview of the topic being discussed. It is essential to include relevant background information on smartphone applications in various research fields. Additionally, apart from discussing lidar applications, it is important to highlight the significance of photogrammetry as another important aspect of smartphone technology. (e.g., https://doi.org/10.1002/esp.3648 ; https://doi.org/10.1016/j.enggeo.2023.107170)
The manuscript should provide a detailed comparison of the iPhone 13 Pro LiDAR scanner's accuracy and usefulness with the professional TLS, highlighting the advantages and limitations of each technology.
The study focuses only on the GG-1 ventilation shaft in Kwielice, Poland, which limits the generalizability of the results. The manuscript could discuss potential implications and limitations of the findings in a broader context.
The manuscript should address potential sources of error in the LiDAR scanning process and how they might impact the accuracy of the measurements and inspections. This would provide a more comprehensive understanding of the reliability of the results.
A more in-depth analysis of the advantages and disadvantages of LiDAR scanning compared to traditional measurement methods are suggested, highlighting any significant differences in accuracy, efficiency, and cost-effectiveness.
While the manuscript mentions the use of open-source software for volume calculation, it fails to discuss the limitations and potential accuracy issues associated with such software. This should be addressed to provide a more balanced evaluation.
The manuscript should discuss any potential environmental or safety considerations related to the use of LiDAR scanning in the mineshaft sinking process. This information is essential for assessing the practicality and feasibility of implementing this technology.
The manuscript could benefit from a comparative analysis between the iPhone 13 Pro LiDAR scanner and other emerging technologies in the field of inspections and measurements. This would provide readers with a broader understanding of the available options.
The implications of the study's findings and potential future research directions should be outlined. This would ensure that readers understand the significance of the results and how they can contribute to further advancements in the field.
Author Response
Dear Sir/Madam
I believe that the introduction covers the issue broadly enough and additional references to literature allow for detailed answers to any questions and doubts. However, as per your review and suggestion, I added the smartphone photogrammetry apps in references 13 and 14. They can be found in lines 42-43. If there is any information missing from the article, I will be grateful if you point it out.
As for iPhone and FARO comparison I added table 6 in which most important properties are compared.
The research focuses on this particular embankment because measurements could only be carried out in Poland on this embankment. I would like to emphasize that the GG-1 shaft was at that time the only deepening shaft in Poland and probably one of the few deepening shafts in the EU. I'm sorry, but collecting data from other wells during the sinking process is beyond the authors' capabilities due to logistical constraints. It should be emphasized that regardless of the location of the shaft, the sinking process is similar and what is important is the demonstrated accuracy of the measurements, assessed on the basis of the repeatability of observations at different depths and therefore in different conditions of the geometry of the shaft being sunk.
Considering potential sources of errors I added lines 162-167 with our experiences in using iPhone 13 Pro for measurements.
As for advantages of iPhone scans compared to classicals method I believe that they are pointed out in lines 198-199. iPhone measurements are less biased while time is similar. As a person who has done classical measurements many times I can say that in many cases measurement is far from perfect due to uneven footwall and sidewall or
The volume calculation is done by multiplying surface of each stripe by its height which was tested from 1cm to 1mm and then compared to real value of concrete used. Stripes are generated based on points coordinates so software accuracy is based on point accuracy and that was already mentioned. It does not matter what program is used for the above procedure. We used the described open-source program because it was convenient for accelerating multiple calculations with stripes of different heights.
Considering safety and environment I would like to highlight that positive impact on safety is mentioned lines 212-221. As for safety of using smartphone in underground mine it is not ex-proof so using it in coal mining is not possible but in copper mine such as KGHM this problem does not occur but I added lines 172-175 about explosion risk.
Unfortunately, the GG-1 shaft is already finished and it is not possible to conduct another comparative analysis, but the obtained observation values and their analysis during construction indicated much better compliance with the design data than classic measurements. This translated into measurable technical and economic benefits related to, for example, monitoring the correctness of concrete consumption in the process of creating the housing.
As You suggested I added lines 378-380 in conclusions where I outline authors belief that such low-cost scanners will be used in future shafts.
Kind regards,
Wojciech Rutkowski – corresponding author
Round 2
Reviewer 2 Report (New Reviewer)
The authors have carefully revised the manuscript and addressed all the issues raised by me. This version can be accepted for publication.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
From the content, this manuscript validates the effectiveness of iPhone 13 Pro in estimating mine volume. The topic is interesting while this manuscript is more like an engineering report. Detailed comments are listed below.
Major
The topic is inspection of mineshaft sinking process while the content is mainly about volume estimation. It seems the topic is not fully focused. As volume estimation is a quite basic processing, no novelty is shown in this manuscript.
The organization is not suitable. Methodology part does not introduce the workflow of the use of iPhone 13 Pro LiDAR on inspection of mineshaft sinking. It seems only traditional methods are introduced.
Others
Figure 4: Theoretically, the accuracy of iPhone point cloud is related with many parameters, such as scanning area at once, scanning range , the operator, etc. The quality of point cloud should be discussed after those conditions are clear. The definition of high or low quality is vague in current description.
lines 15-17: Commonly, validation result and conclusion are introduced at the last of abstract. So suggest move this sentence to the front.
lines 188-190: Remove it.
lines 193-199: Suggest visualizing the reference points.
Table.2 and Table.5: Both tables show the comparison of volume estimation, but the data organization is confusing. In table.2, 7 lining are compared while only one group of data is shown in Table.5. More details about the comparison in Table.5 should be added.
lines 241-242: Contents about pre-inspection of bolting patterns are not discussed in experiment.
Author Response
Dear Sir/Madam,
Thank You for the review, I have to disagree about volume estimation using smartphone in mineshaft sinking condition not being novelty, according to my studies this solution was not yet proposed by anyone in this area. Of course volume estimation in general is basic and well known processing but in GPS-denied, underground mineshaft environment it is quite new. Moreover manuscript is not fully focused on volume estimation, but I understand that other parts were not elaborated enough so I corrected that. I also added part in methodology describing measurements with smartphone. As for point cloud accuracy in figure 4 I meant that quicker scan is blurred and might miss some areas. I elaborated it in the text. According to Your suggestion I reordered abstract, removed lines 188-190, added visualization of reference points. As for table 2 and 5 both show the comparison of volume estimation but in table 2 smartphone volume estimation are compared with real values of used concrete and in table 5 comparison is done between volume estimated from two scans. Due to technical and time constraints only one interval was scanned both with smartphone and TLS. Last but not least pre-inspection of bolting patterns are discussed in part 3.1 but I elaborated it so it is more visible.
Yours sincerely Wojciech Rutkowski
Reviewer 2 Report
This paper presents an interesting implementation of the LiDAR facility of iPhone 13 in really adverse conditions of a mine pit. However, the comparison and accuracy evaluation are not adequate enough. Firstly, there is no mention of the initial specs and accuracy requirements for this kind of application. Only at the end, there is a comment that the 2 cubic meters difference is within the limits! Secondly, the assessment of the iPhone LiDAR is also missing. Reference to a paper for iPhone 12 is not enough. Moreover, the effect of the adverse conditions in 1200m depth is not handled in the paper as it should be. Finally, some English language corrections should be performed.
There are some expressions in English that should be corrected. Minor checks.
Author Response
Dear Sir/Madam,
Thank You for the review, I would like to start with initial specs and accuracy required for this application. Generally there were no initial requirements. For shift handover part the main requirement is possibility to let next foreman or manager see what is currently underground. For rock bolts distances check accuracy should be lower than maximum deviation form the project which is 10% in case of KGHM regulations. As for concrete assessment 2m3 accuracy is great improvement from currently used method described in manuscript. iPhone LiDAR assessment was done in section 4.1 “Accuracy comparison between iPhone 13 Pro and FARO FOCUS 130”. For validation purposes two point clouds were aligned using iterative closest point (ICP) algorithm and distanced between points were calculated with CLOUDCOMPARE feature “cloud to cloud distance”. Results are also presented in the manuscript. I corrected chart 1 and now it is clearer to read. Please find every correction I have made in new version of manuscript.
Yours sincerely Wojciech Rutkowski
Reviewer 3 Report
In general this is an interesting paper that could be published. However it needs some editing and some more information needs to be given.
The paper lacks information how georeferencing was done. This is important also because the paper suggests that this will be a repetitive survey thus this is needed. Also the accuracy of this feet needs to be given.
Also the authors neglect to say what mode of IPhon LIDARA app they are using and since LIDAR app partly works on SfM this is important. I would also like to know what were the light settings during the survey and is they have been changed from that is in the shaft for this experiment.
L9 remove ‘workings’ also calling Iphone a scanner is not 100% right – it is a a scanning app or a scanning device
L9 Lidar scanner is too much
L26 “Although such methods are reliable and familiar 26 from many years of practice, there is nevertheless room for improvement with the use of 27 new technologies” change to “Although such methods are reliable and have been tested over the years, there is still room for improvement”
L40-41 needs a grammar check
L44 augmenting??
L146 time consuming
L145-152 this whole part is not written in a clear way and needs explanation
L172 remove sight
L180-201 – EDITING!
Cart 1 (it is not exactly a chart) is unreadable – pleas edit the scale
L211 – accuracy and method of this alignment is needed
The language is OK
Author Response
Dear Sir/Madam,
Thank You for the review, I would like to start my reply with georeferencing. Inspections were not georeferenced at all. Although surveys were repetitive there was no necessity to link scans between themselves, so every scan in single entity. In most cases it was just scan with PolyCam application in LiDAR mode with auto(video) recording. As for light, correct measurement required additional lamps, it was set of 3 bosch 1900 lumens battery lamps. I also corrected every suggestion that You made. Alignment in L211 was made using four point of interest. They were visible on both scans and were used to align both point clouds. Accuracy of those point alignment is mentioned in table 3. Alignment was done using iterative closest point (ICP) algorithm. Please find every correction I have made in new version of manuscript.
Yours sincerely Wojciech Rutkowski
Round 2
Reviewer 1 Report
Reviewer has to disagree with author’s disagree. From the view of actual operation, using smartphone may make some difference. But actually and substantially, it is to use point cloud for volume estimation, which has been fully resolved. If it hasn’t been resolved, how can authors just use software to compute volume? Indeed, this function has been embedded in many softwares. It is unreasonable to regard using point cloud (even captured from smartphone) to estimate volume as novelty. Effective and more combination between professional area (such as inspection of the mineshaft sinking process) and specific technology can create novelty instead of discussing volume estimation all times.
Besides, it seems authors misunderstand reviewer by stating “Moreover manuscript is not fully focused on volume estimation, but I understand that other parts were not elaborated enough so I corrected that.” First, almost nothing is corrected. Second, reviewer means the manuscript is not focused on the title ”inspection of mineshaft sinking process”, especially in experiment and discussion, which are all talking about volume. So what is the realtion between volume estimation and the title?
In total, now that so large divergence exists and considering authors’ low willing for revision and response, reviewer has nothing else to add about the second version, which is almost the same to the first.
Author Response
Dear Sir/Madam,
Thank Your for second review, because it inspired me to add more content. I added subsections about using iPhone scans for safety reasons and basic geometry control of steel formwork used in our cycle, I believe now manuscript is more diversed and not focused only on volume measurement. Please find listed changes in cover letter and in the manuscript.
Yours sincerely, Wojciech Rutkowski
Reviewer 3 Report
Dear author I do agree you do not need to georeference scans in this case, however I fail to see how you can compare point clouds without registering them to one coordiante system. I think, but looking at the text is just a guess now, that you did target registration in this example since both data were taken roughly at the same time.
What the text is is missing is
- accuracy of this alighment for both point clouds
- If this time of registration would be good for long therm usage of the Iphone.
Also the information about light settings should end up in the paper.
Author Response
Dear Sir/Madam,
Thank Your for the second review. I added all missing informations and clarified part about alignment, it was, as You guessed, aligned with registered characteristic points and yes, both scans were taken in more or less the same time.
Yours sincerely, Wojciech Rutkowski
