One-Degree Imager (ODI), WIYN Observatory Design a Better Miter Saw Design a Better Guard © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard You know the speed of the motor 4800 RPM You know the speed of the blade 1100 RPM (18.3 Hz) © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Will the guard excessively vibrate? ? © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Initial Design Frequency Goal SolidWorks Reports >23.8 Hz 10.2 12.4 16.6 18.8 5.0 Hz Hz Initial Design Will Vibrate Excessively © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Design Change 1: Increase overall wall thickness from 3mm to 4mm (Increases weight 30% over initial design) Frequency Goal SolidWorks Reports >23.8 Hz 10.2 15.4 20.6 25.2 5.0 Hz Hz Design Will Not Vibrate Excessively © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Design Change 2: Use 3mm wall thickness and add external ribs (Increases weight 1% over initial design) Frequency Goal SolidWorks Reports >23.8 Hz 13.9 19.5 2.0 Hz 5.6 9.8 Hz Initial Design Will Vibrate Excessively © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Design Change 3: Use 3mm wall thickness and added internal ribs (Increases weight 1% over initial design) Frequency Goal SolidWorks Reports >23.8 Hz 27.7 13.9 2.0 Hz 5.6 9.8 Hz Design Will Not Vibrate Excessively © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Best Design 30 minutes design iterations prototypes © 2008 Dassault Systèmes SolidWorks Corp Confidential Vibration Analysis Results Blade Speed 1100 RPM (18.3 Hz) 10 First Weight Weight Natural (grams) Increase Frequency (Hz) RPM Percentage Over Running Speed 18.8 1128 3% 30% 1% 25.2 19.5 1512 1170 37% 6% 1% 27.6 1656 51% Wall Thickness Rib None 267 None Outside 348 270 Inside 269 © 2008 Dassault Systèmes SolidWorks Corp Confidential ... Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Will the guard excessively vibrate? ? © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Initial... Vibrate Excessively © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard Design Change 2: Use 3mm wall thickness and add external ribs (Increases weight 1% over initial.. .Design a Better Guard © 2008 Dassault Systèmes SolidWorks Corp Confidential Design a Better Guard You know the speed of the motor 4800 RPM You know the speed of the blade 1100 RPM