Efficiency Improvement using CAE Automation Tools Praneet Gupta Senior Manager Maruti Suzuki India Limited Gurgaon Palam Road Gurgaon-122015 (India) Praneet.Gupta@maruti.co.in K Arun Kumar Manager Maruti Suzuki India Limited Gurgaon Palam Road Gurgaon-122015 (India) KArun.Kumar@maruti.co.in Punit N Kharwar Deputy Manager Maruti Suzuki India Limited Gurgaon Palam Road Gurgaon-122015 (India) PunitNarendra.Kharwar@maruti.co.in Abbreviations: ARD Automated Reporting Director, MVD Model Verification Director, CAE Computer Aided Engineering, CAD Computer Aided Designing Keywords: CAE Process Automation, Hyperworks Directors, ARD, MVD, CAD Data Verification, Post Processing, Automated Report, CAE Efficiency Improvement, Customization. Abstract Virtual validation plays an eminent role in reducing the overall product development time. For a CAE engineer, the challenging task is to reduce the virtual validation cycle time with every subsequent new product. Virtual validation tasks begin from CAD data verification and continued till the report making and result interpretation. CAD data checking and making detailed analysis report are the other time consuming process in addition to the modeling task. Identification of the CAD data penetration regions and giving feedback to design team for CAD data modification consumes considerable time. Similarly while making detailed analysis report it is required to report each of the critical panel and spot weld regions so that constructive feedback can be given to the design team. The manual procedure of CAD data verification and report making become more tedious and time consuming tasks if it is the case of complete BIW. This paper focuses on the upcoming technologies, MVD (Model verification director) and ARD (Automatic reporting director) using which CAE analyst can save the substantial amount of time spent on CAD data checking and detailing out the report. Using these automation tools, manual intervention is lessened and CAE analyst can focus more on understanding the dynamics of the problem and result interpretation. Introduction In order to meet the demands for shortening vehicle development cycles and to reduce the development cost, dependency on virtual validation process has increased. This requires CAE engineer to provide quick and accurate feedback to the design teams in minimum possible time. Apart from the regular CAE evaluation job, another important challenge to the CAE engineer is to review the existing CAE processes regularly and to work for CAE process efficiency improvement. To improve the process efficiency and speed up the CAE evaluation process, the key approach is the implementation of automation at every possible step. Automation also ensures process consistency, accuracy, and elimination of human errors. The best way to automate any process is to capture the best practices from senior analysts and automate it using CAE customization tools automate it. In the present context of work, it is highlighted that how customized tools have aided in automating important steps of CAD to CAE evaluation process there by improving overall efficiency. The Latest versions of Altair Hyperworks include MVD and ARD directors that allow automation of CAD data verification and report making processes. Virtual Validation Process Any CAE process starts from CAD data verification and it ends with giving feedback to the design teams by releasing the report. Apart from the time consuming modeling time, the other two activities which consume substantial time are CAD data verification and making detailed report. The detailed report includes reporting of panel and spot weld stress. These two activities cumulatively consume 16% man-days of CAD to CAE Evaluation Process. CAD to CAE evaluation turnaround time is crucial in providing optimal solutions in minimum time. The conventional process followed at any company from CAD to CAE evaluation is shown below (Figure 7). 1
Figure 1: CAD to CAE evaluation Conventional Process By using two important Hyperworks directors MVD and ARD, human intervention is reduced and the effort required to complete the CAE task is reduced by at least 13 % man-days. The new CAE process is shown below in Figure 2. These two applications of MVD and ARD manage the faster creation of the finite element mesh and report by automating the tasks performed by the CAE specialists. Figure 2: CAD to CAE evaluation New process 2
DAD Data Verification using Model Verification Director (MVD) CAD data verification process is first and important step in CAE activities. At this stage key focus is on filtering and reporting CAD errors and identifying common mesh by comparing the new CAD with mesh data in existing vehicle database. The challenge is to ensure the CAD data is error free in minimum possible time. By using MVD director, CAE analyst can perform three important activities as listed below. 1. Checking CAD errors Checks all the components for the CAD error like component intersections & Part mismatch. It highlights all the error locations with cross mark symbols. Automatic report generation in presentation format which is 3D interactive report in which error locations can be viewed directly in Hyperview player. 2. Comparing CAD & Mesh data and identifying the similar & dissimilar regions. Compares geometry, thickness, & materials of one model with respect to reference model. It can be performed on CAD-Mesh or Mesh-Mesh or CAD-CAD combinations. It mainly identifies and differentiates matching and un-matching areas of two compared parts. Comparing same stage CAD & Mesh data and finding mesh accuracy in terms of percentage (%age) of matching. It highlights how close the CAD is captured with mesh. Automatic report generation in excel format which is again 3D interactive report in which all the compared parts listed part by part and can be viewed directly in hyperview player. MVD differentiates matching/un-matching areas with two different colors and % value is printed against each part. 3. Checking Spot weld errors Checks all the spot weld connection and identifies spot weld errors like missing spot welds, spot welds on features & fillets etc., and highlights error locations with cross symbol. Automatic report generation in presentation format which is 3D interactive report similar to CAD error report. In all the above cases, MVD generates ready to use reports. These reports can be directly sent to the concerned designer/analyst as a feedback. These reports are 3D interactive and designer/analyst can directly view the concerned parts or area in hyper view player. Designer can easily view the concerned area in the Hyperview player and can do the necessary changes. The below image (Figure 3) shows few glimpses of MVD CAD Error report. It can be seen in the below image that all the error locations are identified & marked with cross symbol. After CAD Error report is generated it is directly send to the concerned designer for CAD corrections. The designer can directly view components in hyperview player and quickly locate the error locations which is time saving as compared 2D static image. Similar kind of report is generated in spot weld error check, highlighting all the error spot weld locations. 3
Figure3. CAD Intersection errors MVD report For every new developed model there is commonality between the new model parts and benchmark model parts. Besides identifying the common and uncommon panel area by MVD the additional useful feature is to ensure the quality of the meshed model. The below image (Figure 4) shows few glimpses of MVD comparison report in which the new model CAD data & existing benchmark model mesh is compared part by part to identify the common and uncommon areas. Based on this comparison report, analyst can estimate the time required to model uncommon areas and subsequent plan of action is made to model the uncommon areas. Figure 4: CAD to Mesh comparison MVD report 4
The conventional approach of checking the Mesh/CAD data component by component and providing feedback to the design team for CAD corrections consumes significant time and there is always a possibility of human error in manual process. By using the new approach using MVD, process has been automated and 80% time reduction is achieved in CAD Verification process. And the process time has been reduced from 9% man-day to 2% man-days of CAD to CAE evaluation process. Post Processing & Report generation using Automatic Reporting Director (ARD) Post Processing and Report generation is the last step in CAD to CAE evaluation process which is a tedious time consuming task as CAE Analyst has to study and report the results in detail. In this step, the key focus is on identifying the hotspots per each load case in BIW and capturing the images of those locations and placing them in the report in proper layout. In addition of reporting high stress location, Analyst has to prepare bill of materials of concerned parts and describe the loads and boundary conditions used in the model. Altogether consumes around 7% man-days of CAD to CAE evaluation process. Automatic Reporting Director (ARD) is one of the Hyperworks director which enables automatic generation of customized report as per our requirement. With some additional customization to the existing base solution, post processing and report making can be automated which reduces the manual intervention to the large extent. ARD can be accessed through Hyperview menu bar under directors menu by selecting the option ARD. Below figure (Figure 5) shows the GUI of ARD. Custom Template Selection: Figure 5: Automated Reporting Director GUI Based on type of report to be prepared, the respective template is loaded from the Report template selection box. In the subsequent selection boxes analysis models and result files are loaded. Custom GUI Tab: Custom Tab GUI is made based on post processing requirement and user input required to generate the report automatically. Following image (Figure 6) shows the glimpses of Custom Tab GUI to feed the user input. 5
6: Automated Reporting Director Custom Tab GUI Figure The important tasks performed by the ARD module are: - Reading the Solver input file format and results format in Hyperview. - Reads information from the Bill of materials thereby generating part numbers, thickness and material details in the tabular format for user selected parts. - Reading the stress data and pointing out the high stress locations as per the user defined threshold range. - Giving collective information about the total number of weak panel and spot welds regions in BIW. - Comparing the result of two models (Model-A and Model-B) if required. - Differentiation of various hotspot locations as per the user defined classification like not acceptable locations and warning zone locations. - Capturing the images of concerned locations and placing them in the user designed layouts. - Capturing Loading and boundary condition details from the model and inserting into the report. Below image (Figure 7) shows the glimpses of report generated by Figure 7: Report - Automated Reporting Director 6
The new approach using Customized ARD, post processing & Report preparation time has been automated and 85% time reduction is achieved. The process time has been reduced from 7 man-days to 1 man-days in CAD to CAE evaluation process. Results & Discussions The traditional approach of checking the Mesh/CAD data component by component and providing feedback to the design team for CAD corrections and doing post processing & preparing the report without any automation consumes significant time and there is always a possibility of human error in manual process. The conventional approach of CAD Verification & Report generation process consumes 9 man-days and 7 man-days respectively in CAD to CAE evaluation process. By new approach using MVD & ARD, CAD Verification and Report generation time has been reduced by 80% and 85% respectively. Overall CAD to CAE evaluation process time is reduced from 16 man-days to 3 man-days and efficiency is improved by 13%. Benefits Summary There are multiple Benefits of using MVD & ARD director. CAE analyst can anticipate the modeling time required to complete the FE model of BIW and schedule the tasks accordingly. CAD errors can be quickly filtered in early stage of CAE process and feedback can be sent to the design team. The common and uncommon regions of BIW can be easily identified and focus can be given to the uncommon regions. Common mesh available in existing BIW models can be identified and utilized in new models. After completing the meshing work CAE analyst can judge the quality of mesh by comparing it with the CAD data. Automatic generation of ready to use 3D interactive reports. Post processing time can be reduced significantly by setting the model and results automatically. Automatic identification of hotspots in BIW and capturing those locations and placing them in the user designed layouts Automatic report generation with minimum manual intervention. Key Challenges The key challenge was capturing the best practices followed by CAE domain experts and customization of those practices in MVD and ARD tools. In the ARD tool some of the biggest hurdles were to identify the high stress locations and distinguishing between the panel and spot weld stress and placing the images as per user selected layouts. Future Plans To further reduce the model import and validation time in Hyperview, integration of MVD with the team center engineering software will be explored so that CAD data can be directly read into the Hyperview. As of now the module of ARD is being developed mainly for Durability domain but in future it shall be implemented for NVH and Crash domains also. Conclusions The installation of MVD and ARD modules is quite easy. It requires minimum IT effort to install, configure and maintain. Both the tools are simple and intuitive to use. The inventive feature of this tool is that it has automated the tasks of CAD data verifications and report making which historically have been performed manually, and requires extensive human and time 7
resources. A major portion of work routinely carried out in CAE activities is now performed automatically and supervised by CAE analysts, thereby increasing efficiency. The CAE specialist can focus his time on solving problems and result interpretation rather than spending time on CAD data checking and report making. Altair Hyperworks directors have provided the required tools to build the knowledge into Hyperview and automate the repetitive task and avoid non value added activities. ACKNOWLEDGEMENTS The authors acknowledge the kind support of Maruti Management and Altair ARD & MVD support teams for this work. The authors would like to thank Mr. M V Surendra Reddy and Mr. R Radhesh Kumar for customizing the ARD tool as per MSIL requirement. REFERENCES [1] http://www.marutisuzuki.com [2] MVD, http://www.altair.com/company.aspx?t=2&top_nav_name=services&item_name=model%20verification%20director [3] Process Automation, http://www.altairpd.com/page.aspx?category=what-we-do&item=process-automation 8