Search or add a thesis

Advanced Search (Beta)
Home > Development of an Integrated Framework for Optimization of Sheet Metal Work Through Bi-Directional Information Flow Between Design and Manufacturing Processes.

Development of an Integrated Framework for Optimization of Sheet Metal Work Through Bi-Directional Information Flow Between Design and Manufacturing Processes.

Thesis Info

Access Option

External Link

Author

Faraz, Zahid

Program

PhD

Institute

National University of Sciences & Technology

City

Islamabad

Province

Islamabad

Country

Pakistan

Thesis Completing Year

2016

Thesis Completion Status

Completed

Subject

Mechanical Engineering

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/10197/1/Zahid_Faraz_Mechanical_Engineering_2016_HSR_NUST_15.11.2016.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727733179

Asian Research Index Whatsapp Chanel
Asian Research Index Whatsapp Chanel

Join our Whatsapp Channel to get regular updates.

Similar


Present day low quantity, high variety, and make-to-order manufacturing scenario demands concurrent product development. Major attributes required for concurrent product development are: seamless and bi-directional data flow among design, manufacturing and quality control cycles. This thesis documents research in to the field of generic feature based design and manufacturing process planning of discrete sheet metal bend parts. In this context sheet metal forming is subjected to various variations, due to which state of the art in sheet metal pressbrake forming is still recognized as a separate and vague island of automation. Formal integration of standards and specifications is required for knowledge retrieval, generated during manufacturing phase. Sheet metal pressbrake forming is subjected to various process and material variations and ultimate shape of a 3D formed part depends upon the capability and health of the equipment of a native manufacturing setup. Process planning and process parameters are optimized by altering some of the design attributes. Valuable knowledge generated during this activity is lost and is not communicated back to the upstream design stage. This research highlights several issues regarding feature based design and manufacturing of discrete sheet metal parts. Contemporary standards STEP (STandard for Exchange of Product data) and STEP-NC ( STandard for Exchange of Product data for Numerical Control ) are utilized to formulate a framework for feature based design and manufacturing of discrete sheet metal parts augmented with the capability of knowledge retrieval. Major contribution of this research is a proposed framework for feature based design and manufacturing of discrete sheet metal parts developed on the basis of STEP and STEP-NC standards. It outputs a generic feature based manufacturing process plan that could be mapped and optimized according to the capabilities of a native manufacturing environment. In the proposed framework STEP enabled manufacturing process plan communicates generic information independent of any vendor specific detailing which is mostly based on rigid data formats such as ISO 6983. Functional requirements of the framework are categorized into three independent modules for the CNC pressbrake process control unit: 3 (1) Feature based design development of discrete sheet metal parts (2) Generic feature based process planning of discrete sheet metal parts (3) Offline process plan optimization according to the capabilities of a native manufacturing environment. The framework was validated through experimentation on a CNC pressbrake with 3-axis back gauge locating capabilities. STEP & STEP-NC compliant framework for feature based design and manufacturing of discrete sheet metal parts provides a powerful tool for generating generic process plans and knowledge retrieval generated during final process plan optimization and execution. Prototype system using ST-Developer® Visual C++ libraries is developed to demonstrate the functionality of the proposed framework.
Loading...
Loading...

Similar Books

Loading...

Similar Chapters

Loading...

Similar News

Loading...

Similar Articles

Loading...

Similar Article Headings

Loading...

مبشر سعید

کوئی ملتا ہی نہیں سوختہ پا میری طرح
جس کو معلوم ہو وحشت کا پتا میری طرح
میرے جیون کو اُداسی سے ملانے والا!
دشت میں پھِرتا رہے آبلہ پا میری طرح
میں نے احباب کو آواز لگا کر پوچھا
کوئی رہتا ہے شبِ غم میں سدا، میری طرح؟
اے کئی دن سے مرے ذہن پہ چھائے ہوئے شخص
تو مجھے وصل کے سپنے نہ دکھا میری طرح
رات بھر چاند کو احوال سنانے کے لیے
کیا ٹھہرتی ہے دریچوں میں ہوا، میری طرح؟
زندگی! میری طرف دیکھ کے ایماں سے بتا
ایک بھی شخص کوئی تجھ کو مِلا، میری طرح
تند اور تیز ہواؤں کے علاقے میں سعید
زیست کرتا ہے فقط دل کا دِیا میری طرح

Analisis Pola Komunikasi Interpersonal: Fondasi Pilar Keluarga Sakinah

This study addresses the issue of interpersonal communication patterns in establishing a harmonious family.  Communication is emphasized in the holy Qur'an as a crucial aspect of human life, particularly for Muslims. Poor communication is one of the factors that can lead to marital disharmony or discomfort within the family. Therefore, effective communication is essential for a healthy family life. To achieve a harmonious and content family, it is essential to understand the patterns of interpersonal communication within the family. This will lead to a peaceful and comfortable environment for all members. The authors aim to discuss effective communication techniques, both in general and within a religious context, to establish a happy family. The research focuses on examining theories related to positive communication patterns within the family. The methodology employed for this research is library research. A balanced communication pattern is essential for forming a harmonious family. Additionally, precise subject-specific vocabulary should be used when it conveys the meaning more precisely than a similar non-technical term. This involves open communication where each member has an equal opportunity to express their opinions about family life. It is important to avoid any biased or emotional language and to use clear, objective, and value-neutral language. The text is grammatically correct and follows conventional academic structure and formatting. No changes in content have been made.

Efficient Utilization of Bandwidth for Ofdm Wsn

Wireless Sensor Networks (WSNs) have gained popularity in a lot of emerging areas since their evolution, like the monitoring of natural phenomena concerning geosciences in various disciplines. Some relevant areas include the monitoring of oil and gas exploration field, earth quake and volcanic eruptions etc. In these processes real time phenomena are monitored in remote fields and after data collection through WSN, it is ported to the far flung research centers for further investigation and decision making. Here 2-tier WSN is considered with lower tier of sensor nodes in WiFi and upper tier of WiMAX as a backhaul for data transportation to distant research facility. However WiMAX has already popularity for applications with main configuration of downlink data delivery direction, like serving internet hot spots and similar amenities. This innovative research work is concerned with previously mentioned phenomena monitoring which needs high data throughput efficiency in the uplink direction. For dense sensor node concentration, in order to transport consolidated output form all sensor nodes in real time phenomena of impulsive nature, sufficient uplink throughput is needed with low latency which forms a bottleneck in these cases for WiMAX backhaul. Real time applications constrain end-to-end delay and hence throughput which severely affect the performance and the accuracy of the monitoring. To the system only fixed bandwidth is available, for which resources of slots have to be shared between downlink and uplink. Here WiMAX OFDM in TDD mode is considered. Initially analysis has been presented to point out main important constituent parameters of WiMAX which contribute to throughput. This research work proposes a solution to enhance uplink bandwidth allocation efficiency for these phenomena through adaptive shift of WiMAX frame ratio. In this regard for WiMAX adaptive ratio shift researchers have used a number of scenarios but all of them are not very efficient and have drawbacks. Some of them are using either fixed margins or some other are using fixed step sizes for upward or downward (increment) without any calculation. If a link (uplink or downlink) is running near full capacity then any kind of sudden appearance of internal system overheads in the form of system message or broadcast may bring the link to fragmentation. And fragmentation successively may contribute to increase the link overheads further, causing either increased delay or some other problem related to packet drop, re-transmission or transmission failure. If problems are induced, this may take relatively longer at a reduced data transfer rate. In order to avoid similar problems, relevant calculations have to be performed to guarantee good QoS values of maximum link throughput while keeping low delay and packet drop, which needs adequately more resources. In fact keeping in view the complex trade-off between QoS parameters and system resources, the optimization problem is formulized to maximize the uplink throughput while keeping the latency and packet drop of downlink to minimum limit, to facilitate the efficient operation of uplink’s momentarily bulky traffic. A novel solution to this problem is obtained through the incorporation of stochastic processes with random variable in finite state space. The analytical and mathematical expressions are contributed for the different analytical models. A MMPP traffic model is formed for OFDMA transmission. This is supported with a DTMC system model for queuing theoretic performance modeling. Analytical and numerical values of performance parameters like throughput, packet delay and probability of packet drop are estimated for resource allocation through mathematical models of stochastic process. First of all to restrict the downlink traffic to minimum level a traffic pattern is defined from downlink to WSN sensor nodes. While considering packet scheduling, two scenarios are taken into account, one is concerned with known MCS distribution and the other is concerned with unknown MCS distribution. In this process mainly affecting factors of frame overheads are also taken into account. Then by using all these analytic and mathematical models, an algorithm is formulated to find out minimum optimal resource requirement on down link after considering these QoS parameters. Through this manipulation rest of the resources can be transferred to facilitate uplink operation. Another DTMC model is designed to check and quantify the uplink frame utilization. When uplink frame utilization is beyond normal, the frame resources have to be incremented to previously calculated maximum limit by adaptively remapping the frame ratio. Also when utilization on uplink reduces below normal, it is remapped to normal frame ratio. The main algorithm is formed by appropriately including all these previous analytical models. This sets the adaptive ratio to the best suitable maximum value, to facilitate the uplink bulky traffic, and saves the link from congestion and slowing down. This also ensures minimization of previously mentioned errors of delay, drop or timeout related problems. This process achieves highest degree of convergence in just one step by providing maximum throughput on uplink without degrading QoS parameters on the downlink operation. In order to prove the results firstly analytical results are obtained from the computations of the algorithm in MATLAB. Secondly intensive simulations are conducted around Rayleigh flat fading channel through models in three steps. One simulation model gives results for downlink minimum traffic, next model is for uplink maximum traffic and another model is for uplink normal ratio traffic. All these results together prove the accuracy and superiority of the algorithm by showing an outstanding uplink bandwidth efficiency enhancement without degrading the downlink operation. Future research directions are to further enhance the analytical models for more states. Also more variations to overhead analysis can be added by more realistic models and with more overhead reduction techniques.