Here are some of our sample calculations:

 

Equation Used to Calculated Gear ratio for Cutter

 

VR= D2/D1 = 1.783in/.764in= 2.33

 

Equation used to calculate Cutter RPM

 

W2= D1ω1/D2 = .764in*10500rpm/1.783in= 4499 RPM

 

Equation used to find torque on cutter shaft

 

Torque out= Torque in * Gear Ratio = .97ftlb *2.33= 2.26ftlb

 

Equation used calculate stress in a beam in bending

 

σ = MC/I = 35.25lbin*.25in/.00346in^4 = 2546.965PSI

 

Equation used to find factor of safety in above beam

 

Ultimate Strength/ Stress from bending = 570000psi/2546psi= 22

 

Equation used to Determine run time

 

Battery Amp hour/ Estimated current draw in 1 hour

 

75AH/( 15A+15A+5A) =2.14 Hrs

 

Below lies the results from the stress calculations of the chassis

Beam Max Shear Max Moment Max Stress Ultimate Str. FOS
  LB INLB PSI PSI  
A 28.39 198.73 7179.5 57000 7.939272
B 4.94 0 269 57000 211.8959
F 23.5 35.25 2546.9653 57000 22.37957
C 11.75 30.8 2225.4335 57000 25.61299
L 10 98.98 7151.7341 57000 7.970095
I 12 78 5635.8382 57000 10.11385
Shaft   Max Torque      
A 1263.88 27 1263.88 18000 14.24186