![](https://static.wixstatic.com/media/12fdfe_7c882d0fb2134c94a5e371be5afe8865~mv2.png/v1/fill/w_378,h_600,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_7c882d0fb2134c94a5e371be5afe8865~mv2.png)
Justin W.H. Yuen
![](https://static.wixstatic.com/media/12fdfe_da101a81336c402fba69baf66d29fe13~mv2_d_5312_2988_s_4_2.jpg/v1/fill/w_658,h_370,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_da101a81336c402fba69baf66d29fe13~mv2_d_5312_2988_s_4_2.jpg)
Reverse Engineering an Umbrella Handle
I had to model an object with complex shapes for a class project. What came to mind was an umbrella that was uncomfortable to hold. I went beyond the expectations of simply modeling the handle by making the CAD model easy to modify for redesigning a more ergonomic handle.
Computer Aided Design Course, Spring 2018
Goal
Make a CAD model of an existing umbrella handle to design a new ergonomic handle
Results
A CAD model of an umbrella handle with a more ergonomic grip that can easily be redesigned
Modeling the Original Handle
![](https://static.wixstatic.com/media/12fdfe_92d5bba3d5e64c7e93d6938206ac9621~mv2.png/v1/fill/w_961,h_614,al_c,q_90,usm_0.66_1.00_0.01,enc_auto/12fdfe_92d5bba3d5e64c7e93d6938206ac9621~mv2.png)
![](https://static.wixstatic.com/media/12fdfe_9d5c763132a64af8a574e5025df27ba0~mv2.jpg/v1/fill/w_544,h_306,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_9d5c763132a64af8a574e5025df27ba0~mv2.jpg)
I used the Surface Sweep feature on SolidWorks to capture the shapes of the handle. This approach makes redesigning easier because I could make big changes to the shape by simply changing the guide curve.
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The guide curve of the original handle was captured by a contour gauge, shown on the left.
The length of the path was measured with a caliper.
![](https://static.wixstatic.com/media/12fdfe_9d72369d7c11474395289341c62150e2~mv2.jpg/v1/fill/w_594,h_334,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_9d72369d7c11474395289341c62150e2~mv2.jpg)
![](https://static.wixstatic.com/media/12fdfe_840086ddb4df4eaf867db3bca3f59c22~mv2.jpg/v1/fill/w_594,h_333,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_840086ddb4df4eaf867db3bca3f59c22~mv2.jpg)
The profile of the bottom face of the handle was traced onto paper.
![](https://static.wixstatic.com/media/12fdfe_46a869cb8b294ac082bc61f09a899bb9~mv2.png/v1/fill/w_690,h_569,al_c,q_90,enc_auto/12fdfe_46a869cb8b294ac082bc61f09a899bb9~mv2.png)
Finger and palm grips modeled using surface sweeps
![](https://static.wixstatic.com/media/12fdfe_4736a2eb7121449a851c5cce3134bb0d~mv2.jpg/v1/crop/x_480,y_0,w_771,h_706/fill/w_454,h_416,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_4736a2eb7121449a851c5cce3134bb0d~mv2.jpg)
![](https://static.wixstatic.com/media/12fdfe_25e2b1b5619e4af6a84142d20db336ad~mv2.jpg/v1/crop/x_443,y_0,w_802,h_703/fill/w_475,h_416,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_25e2b1b5619e4af6a84142d20db336ad~mv2.jpg)
![](https://static.wixstatic.com/media/12fdfe_8adb4eb5bd7a4f91a63ba29d63fe30e6~mv2.png/v1/fill/w_457,h_564,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_8adb4eb5bd7a4f91a63ba29d63fe30e6~mv2.png)
![](https://static.wixstatic.com/media/12fdfe_a0bddd7aa6de44f1b33de4d8b0dec318~mv2.png/v1/fill/w_446,h_556,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_a0bddd7aa6de44f1b33de4d8b0dec318~mv2.png)
![](https://static.wixstatic.com/media/12fdfe_b9009288aa98482dad387ff11fe51cc6~mv2.png/v1/fill/w_451,h_567,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_b9009288aa98482dad387ff11fe51cc6~mv2.png)
![](https://static.wixstatic.com/media/12fdfe_2942c3c4296046c9bd586f819cdd03ec~mv2.png/v1/fill/w_341,h_567,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_2942c3c4296046c9bd586f819cdd03ec~mv2.png)
Comparison of the CAD model and the original handle
Redesigning for an Ergonomic Grip
I redesigned the handle to fit my personal hand by using modeling clay to capture the shape of my hand when I grip a cylindrical object. Following the same method as modeling the original handle, I measured the shape of clay using a contour gauge.
![](https://static.wixstatic.com/media/12fdfe_ac7c216f71b445d39f46db5ea73626d2~mv2.jpg/v1/crop/x_519,y_96,w_712,h_665/fill/w_444,h_415,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_ac7c216f71b445d39f46db5ea73626d2~mv2.jpg)
![](https://static.wixstatic.com/media/12fdfe_7dbb075772e34baea5c5d0df2ee4ddfa~mv2.jpg/v1/crop/x_257,y_0,w_923,h_804/fill/w_476,h_415,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_7dbb075772e34baea5c5d0df2ee4ddfa~mv2.jpg)
![](https://static.wixstatic.com/media/12fdfe_8b45c5ceaa0447e8b0e8801897287837~mv2.jpg/v1/crop/x_352,y_0,w_768,h_804/fill/w_493,h_516,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/12fdfe_8b45c5ceaa0447e8b0e8801897287837~mv2.jpg)
![](https://static.wixstatic.com/media/12fdfe_d1e3f627af8843909056034039160c46~mv2.png/v1/fill/w_454,h_556,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_d1e3f627af8843909056034039160c46~mv2.png)
![](https://static.wixstatic.com/media/12fdfe_866de8668e4a476580741bb991185a9f~mv2.png/v1/fill/w_383,h_556,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/12fdfe_866de8668e4a476580741bb991185a9f~mv2.png)
Results and Design Improvements
Modeling the complex shapes was simplified by using advanced SolidWorks features, which allowed for easier modification of the model and design. At the same time, I discovered a fun and quick way to make a handle with a custom fit grip. Adjusting the shape of the guide curve can be done to create a more universal and ergonomic handle.