Computer Aided Drafting Software (CAD) are very powerful tools. Up to this point, I considered myself proficient when it came to designing objects on CAD software such as Autodesk Inventor, Solidworks, and Creo (formally known as ProE). Little did I know that I was scratching the surface of the full potential and utility of these software. A very powerful tool available to me via these CAD software is something called Finite Element Analysis (FEA). FEA is a tool that can be used to run simulations on part performance. This includes observing how an object/assembly reacts to different forces, how it reacts to thermal sources, how parts interact as they move together, and can even be used to optimize a design. This project introduced me to the world of FEA and demonstrated to me how useful it can be. I plan to implement this tool in all of my future projects (where applicable).
Project Goals: The goal of this project was to design an ergonomic pan handle that is both light while conforming to set constraints. The handle can be any design I choose as long as it meets the requirements of the handle. In order to effectively find the best design, a base design must be created on Solidworks and then tested via Finite Element Analysis (FEA).
Learning Objectives: The purpose of this project is to teach me how to use FEA effectively while creating and designing an object. The skills that will be employed throughout this project include:
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Design Constraints and Requirements
There are a few constraints that need to met when designing and choosing the most optimal pan handle for a pan and handle assembly. These constraints are as follows:
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The Design
As I was designing this pan handle, I had two things in mind. I wanted the handle to conform to the natural curves of the hand, making is as comfortable as possible. This would achieve the ergonomic goal of the project. Hence, my decision was to make the entire handle a curve from base to end while making it thicker at the base and thinner at the edge. A consequence of this design as well is that it saves on material as the base needs more material anyways in order to reduce the stress on the handle. To save on more material, a cavity was cut underneath the handle in order to reduce the amount of material and therefore the weight. The second goal was to have holes in order for it to be hung and in order to vent some heat to the environment, making the overall handle cooler to the touch.
As I was creating this design, something I had to keep in mind was that I needed to have the dimensions of the pan reference each other in order to remain proportional. This would be important later on; when the design study was run the computer will automatically change the lengths of some dimensions and regenerate the computer model in order to determine the best design. If the dimensions were not proportional, the design study would ultimately fail because the computer would not be able to rebuild the part.
As I was designing this pan handle, I had two things in mind. I wanted the handle to conform to the natural curves of the hand, making is as comfortable as possible. This would achieve the ergonomic goal of the project. Hence, my decision was to make the entire handle a curve from base to end while making it thicker at the base and thinner at the edge. A consequence of this design as well is that it saves on material as the base needs more material anyways in order to reduce the stress on the handle. To save on more material, a cavity was cut underneath the handle in order to reduce the amount of material and therefore the weight. The second goal was to have holes in order for it to be hung and in order to vent some heat to the environment, making the overall handle cooler to the touch.
As I was creating this design, something I had to keep in mind was that I needed to have the dimensions of the pan reference each other in order to remain proportional. This would be important later on; when the design study was run the computer will automatically change the lengths of some dimensions and regenerate the computer model in order to determine the best design. If the dimensions were not proportional, the design study would ultimately fail because the computer would not be able to rebuild the part.
FEA Analysis
An FEA design study was done on the handle model in order to reduce the mass while conforming to the requirements. To begin, first stress and thermal simulations were performed on the pan and handle assembly in order to establish a base. Next, a design study was started that aimed to change certain dimensions of the pan's handle in order to reduce the overall mass of the assembly while still conforming to the constraints. To optimize the handle, the length of the handle base (from the connection to the pan to the start of the curve), the length of the handle’s curve, the width of the end of the handle, and the thickness of the pan were varied in order to find the best design. After the design study was completed, various designed were generated and the most optimal one was found. Images of the most optimal design, least optimal design, and an intermediate design are below as well as the statistics of each design. The best design was one that was under the max values for stress, displacement, and temperature while being at a weight that was under 3.5 kg.
An FEA design study was done on the handle model in order to reduce the mass while conforming to the requirements. To begin, first stress and thermal simulations were performed on the pan and handle assembly in order to establish a base. Next, a design study was started that aimed to change certain dimensions of the pan's handle in order to reduce the overall mass of the assembly while still conforming to the constraints. To optimize the handle, the length of the handle base (from the connection to the pan to the start of the curve), the length of the handle’s curve, the width of the end of the handle, and the thickness of the pan were varied in order to find the best design. After the design study was completed, various designed were generated and the most optimal one was found. Images of the most optimal design, least optimal design, and an intermediate design are below as well as the statistics of each design. The best design was one that was under the max values for stress, displacement, and temperature while being at a weight that was under 3.5 kg.
Take-Aways
The improved design is makes sense for the following reasons. The base of the handle is short; this part of the handle does not need to be too long because it just needs support the weight of the pan without being over stressed. Hence, this base is as short as possible, saving on material. Further, the handle’s length and end width was optimized such that is was able to radiate enough heat away such that it does not become too hot. The holes by the base of the handle also do this, which has the consequence of saving on weight. And finally, the pan thickness was reduced simply because it does not need to be as thick in order to meet the requirements, saving on weight again. All in all, the final design is a pan handle that does not max out stress, displacement, or temperature while being as light as possible.
Some designs are better than others because they find a balance between the dimensions and the tolerances. For some designs, the dimensions are small and the assembly is light, however with the dimensions that small the handle cannot stand up to the stress and displacement requirements, as evident by the worst design. In other cases, the pan handle is significantly under the required stress, temperature and displacement, however this requires larger dimension which results in a very heavy pan, as result by the intermediate design. The optimal design is logical because it finds a balance between the two, being as small as it can be while still meeting the requirements.
The improved design is makes sense for the following reasons. The base of the handle is short; this part of the handle does not need to be too long because it just needs support the weight of the pan without being over stressed. Hence, this base is as short as possible, saving on material. Further, the handle’s length and end width was optimized such that is was able to radiate enough heat away such that it does not become too hot. The holes by the base of the handle also do this, which has the consequence of saving on weight. And finally, the pan thickness was reduced simply because it does not need to be as thick in order to meet the requirements, saving on weight again. All in all, the final design is a pan handle that does not max out stress, displacement, or temperature while being as light as possible.
Some designs are better than others because they find a balance between the dimensions and the tolerances. For some designs, the dimensions are small and the assembly is light, however with the dimensions that small the handle cannot stand up to the stress and displacement requirements, as evident by the worst design. In other cases, the pan handle is significantly under the required stress, temperature and displacement, however this requires larger dimension which results in a very heavy pan, as result by the intermediate design. The optimal design is logical because it finds a balance between the two, being as small as it can be while still meeting the requirements.