Wireless Sensor Network Aided Assembly Line Monitoring According to Expectations of Industry 4.0
Round 1
Reviewer 1 Report
Dear Authors,
According to recommendation:
"2.2-3 Harmonization and compatibility of new and existing reference architecture models" (i.e. "There is currently a need for harmonization due to the heterogeneous solutions for reference architecture models in the Industrie 4.0-environment. It is recommended that the reference architecture models (both existing and new) are critically reviewed") given by the publication:
DIN and DKE ROADMAP "German Standardization Roadmap Industrie 4.0. Version 4" Standardization Council Industrie 4.0
(SCI4.0 German Standardization Roadmap Industrie 4.0, ver. 4).
How is Your proposal of "adapted WSN supervision system model" can be mapped for example to IIRA or RAMI4.0 reference architecture models?
It would be great to see what is the superiority of Your approach to define layers as compared with IIRA or RAMI4.0.
That is the only question I would like to state.
Regards,
Author Response
Dear Reviewer
First, we would like to thank You for Your review, and the comments You made regarding the paper. We acknowledge, that Your point of view is right.
In this letter we will answer to the question of how our proposal can be mapped to IIRA or RAMI 4.0 reference architecture models, so in the reminder of this letter, we present the mapping to the RAMI 4.0 architecture model, and a comment regarding to the IIRA.
RAMI 4.0 as a reference architecture model consists of the Asset, Integration, Communication, Information, Function, and Business layers. The proposed model in the paper takes into consideration the aspects which have to be considered if an assembly system supervision is the objective, in this specific case the WSN supervision model for localization purposes. The authors proposed a four layer model that consists of the Production, Preparatory, Control, and Management layers.
Considering the Asset layer and the Integration layer of the RAMI 4.0 model, it can be noted that due to the specificities of the WSN and the assembling lines, both layers of the RAMI 4.0 model are referred in the paper as the Production layer. The reason for this was simply the fact that both the physical objects (the assembled parts, i.e. the holders of the parts on the assembly system, as well as the assembling tools and the assembly line itself) and the wireless sensor units which were to make the transition from the physical to the digital world, were attached, i.e. integrated to the above mentioned physical objects. It has to be pointed out, that the WSN provides information by the IEEE 802.15.4 standard. The Communication layer which grants the access to information is the Preparatory layer in the paper that provides for the data transfer, which is done by wired communication (via standard communication protocols). The Information layer of the RAMI 4.0 model is mapped to the proposed one by the Control layer, which evaluates and compares the unified data provided by the Preparatory layer and data provided during the setup of the assembly process. Based on the comparison, the appropriate decision about the assembly process is generated. This task is performed in the proposed Management layer, which is to be mapped to the Function layer of the RAMI 4.0, and is responsible for the assessments of the quality and effectiveness of the process in the assembly system, i.e. for the proper functioning of the system. In the presented solution the Business layer could also be considered to be part of the proposed Management layer, but this is due to the fact that organizational and business processes were not part of the paper, and therefore only the assembly process supervision process was dealt with.
Having in mind that Industry 4.0 is thought as a fusion of Information and Operational Technologies, the fields of mechanical and electrical engineering rely more than ever on the information and communication technology sectors too. Therefore the IIRA perspectives have to be taken into consideration additionally to the RAMI 4.0 especially if an IIoT system is incorporated to the industry. In the paper, this aspect was not discussed directly, because the objectives of the paper concentrated to obtain the required information to be able to supervise the assembling process, more precisely the localization during the process. However, this is one of the directions for future work, to incorporate IIoT aspects to the problem of process supervision in this field. The prerequisites for successful integration in the future are present, because the information obtained, and the information communicated and stored are dealt with by using standard communication protocols, both in the case of WSN and wired communication, so the information which is to be exchanged in the future can be used to define the future activities, the users, objectives, etc.
We sincerely hope that we were able to present a satisfactory answer to your question, and that our approach in dealing with the problem of assembling process supervision complies to the guidelines of the general architecture models defined in the framework of Industry 4.0.
If You have any additional questions, do not hesitate to contact us.
Yours Sincerely,
The authors.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The topic of the paper is interesting and up-to-date. The processing of individual parts meet general requirements of scientific papers except description of research approach. In the paper is no clear description of the research approach. Authors mention main objective in L74 (no information in abstract) and than divide this main objective into partial sub-objective. It is difficult to find answers to these partial elements in the results and in discussion.
It is necessary to improve this interpretation. After that, paper could be accepted for publishing as average paper.
Author Response
Dear Reviewer,
First, we would like to thank You for Your review, and comments You made regarding the paper. We acknowledge, that Your point of view, i.e. Your comments and suggestions are right, and that it is necessary to improve the interpretation of the main objective, as well as to make it easier to find answers to the defined objectives in the results and in discussion.
In this letter we will answer to the comments and suggestions, and will present them item by item. All the improvements will be presented by first giving the present status, and then the suggested improvement.
The majority of the improvements are done in Chapter 3, but also the Abstract and the Introduction are reinterpreted to better suite the purpose of the paper. By doing so, we hope it is now easier for the reader to follow the text and to find the answers to the defined objectives. In this case, Chapter 4, which gives a discussion of the results obtained in the preceding chapter can also be interpreted with more ease.
- Improvement Line 14-16
- Current status
This research introduces an overall assembling process supervision model, which is based on a modified four-layer control system hierarchy that suits the specific requirements of such systems and uses wireless sensor network technology for data acquisition.
- Improved status
This research introduces both an overall customized assembling system supervision model, which is based on a modified four-layer control system hierarchy that suits the specific requirements of such systems and the developed wireless sensor network technology for assembling process management with a particular focus on localization.
- Improvement Line 74-77
- Current status
The main objective of the paper is twofold; to develop an overall customized supervision model that fits the requirements of the assembling systems, and to incorporate wireless sensor network (WSN) technology for assembling process management, i.e. for solving localization problems during the assembling process.
- Improved status
Therefore, the main objective of the paper is to develop an overall customized supervision model that fits the requirements of the assembling systems, and to incorporate wireless sensor network (WSN) technology for assembling process management, i.e. for solving localization problems during the assembling process.
- Improvement Line 300
- Current status
There is the beginning of Chapter 3, but with no introduction.
- Improved status
This chapter presents the test-laboratory setup, the determination and the distribution of the initial off-line RSSI values of the anchors, and the test results and the comparison of the results accuracy in on-line mode, which are required for the assembly system evaluation.
- Improvement Line 300
- Current status
The beginning of this chapter is placed without a separate subchapter.
- Improved status
A subchapter is inserted: 3.1 Laboratory setup
- Improvement Line 300
- Current status
The industrial laboratory used for the experiments is presented in Figure 5.
- Improved status
The industrial laboratory used for testing the proposed model is presented in Figure 5.
- Improvement Line 324
- Current status
3.1 Distribution of the RSSI values of the anchors in of-line mode
- Improved status
The subchapter is moved just after Figure 6, because the two paragraphs before the title belong after the title, and the numeration of the title is changed.
3.2 Determination and distribution of the initial RSSI values of the anchors in off-line mode
- Improvement Line 345
- Current status
3.2 Test results and the comparison of the result accuracy in on-line mode
- Improved status
3.3 Test results and the comparison of the result accuracy in on-line mode
- Improvement Line 352
- Current status
3.2.1 Cumulative distribution function for quality determination in the case of localization
- Improved status
3.3.1 Quality of the localization algorithms
- Improvement Line 353
- Current status
To be able to compare the results, the cumulative distribution function (CDF) was used.
- Improved status
To be able to evaluate the assembly system, i.e. to compare the results obtained, the cumulative distribution function (CDF) was used.
- Improvement Line 365
- Current status
The quality of the localization algorithm can be valued in the case of test points, which have no RSSI values in the RSSI map (test points with unknown RSSI values).
- Improved status
Following that, the quality of the localization algorithm was valued for test points, which had no RSSI values in the RSSI map (test points with unknown RSSI values).
- Improvement Line 375
- Current status
3.2.2 Influence of the anchor structure to the quality of the localization
- Improved status
3.3.2 Influence of the anchor structure to the quality of the localization
- Improvement Line 385
- Current status
3.2.3 Influence of the laboratory structure to the quality of the localization
- Improved status
3.3.3 Influence of the laboratory structure to the quality of the localization
- Improvement Line 401
- Current status
To be able to interpret the results obtained, it has to be noted, that the laboratory, as well as the assembling line itself, consists of metal elements such as tools, holders, cables, etc. therefore at no circumstances could a homogenous distribution be obtained.
- Improved status
To be able to evaluate the assembly system, i.e. to interpret the results obtained, it has to be noted, that the laboratory, as well as the assembling line itself, consists of metal elements such as tools, holders, cables, etc. therefore at no circumstances could a homogenous distribution be obtained.
We sincerely hope that we were able to present acceptable improvements to the paper, and that the presented improvements raise the quality of the paper to the level which is acceptable for publishing.
If You have any additional questions, do not hesitate to contact us.
Yours Sincerely,
The authors.
Author Response File: Author Response.pdf
