Calculation/Research of MS14 Sub-Assembly Weight

Owned by Tommy Tran
Last updated: Jun 09, 2021
3 min read

This page compiles some calculations/assumptions made by @Tommy Tran on August 4th, 2021.

 

Aerobody

Carbon Fiber Panels

Steps:

  1. Find density (kg/m^3) or mass per area (kg/m^2) of prepreg used for manufacturing

  2. Find total volume (m^3) or total surface area (m^2) of carbon fiber panels

  3. Calculate mass (kg) of carbon fiber panels

Step 1 - Density of Material

Material is primarily woven carbon fiber prepreg.

Note: GSM stands for gram per square metre.

Material

GSM (g/m^2)

Source

Material

GSM (g/m^2)

Source

Woven Prepreg

330-980

Carbon Fiber Prepregs Supplier | Call +86 18918009278 (cacomposites.com)

Unidirectional Prepreg

40-460

Carbon Fiber Prepregs Supplier | Call +86 18918009278 (cacomposites.com)

Step 2 + 3 - Total surface area and Mass

Panel

Surface Area (m^2)

Mass (SA x 330) (kg)

Mass (SA x 980) (kg)

Panel

Surface Area (m^2)

Mass (SA x 330) (kg)

Mass (SA x 980) (kg)

Front Passenger Door

0.62397025

0.2059101825

 

Back Passenger Door

0.58076922

0.1916538426

 

Front Driver Door

0.62397025

0.2059101825

 

Back Driver Door

0.58076922

0.1916538426

 

Trunk

1.78484861

0.5890000413

 

Roof

4.05743353

1.338953065

 

Floor Panel Flat #1

 

0

 

Floor Panel Flat #2

 

0

 

Floor Panel Flat #3

 

0

 

Floor Panel Flat #4

 

0

 

Side Panel #1

1.79554567

0.5925300711

 

Side Panel #2

1.79554567

0.5925300711

 

Hood

0.4978644

0.164295252

 

A Bulkhead

0.60443455

0.1994634015

 

C Bulkhead

1.00960754

0.3331704882

 

B Bulkhead 1

0.36814792

0.1214888136

 

B Bulkhead 2

0.36814792

0.1214888136

 

Front Bridge

 

0

 

Mid Passenger Bridge

 

0

 

Mid Driver Bridge

 

0

 

Rear Bridge

 

0

 

Driver Trunk Bridge

 

0

 

Passenger Trunk Bridge

 

0

 

Front Driver W.Cover

0.28933021

0.0954789693

 

Front Pass. W.Cover

0.28933021

0.0954789693

 

Rear Driver W.Cover

0.31471481

0.1038558873

 

Rear Pass. W.Cover

0.31471481

0.1038558873

 

Total

 

4.451589731

13.21987253

 

Thermoformed Panels

Steps:

  1. Find density (kg/m^3) or mass per area (kg/m^2) of thermoformed panel used for manufacturing

  2. Find total volume (m^3) or total surface area (m^2) of carbon fiber panels

  3. Calculate mass (kg) of carbon fiber panels

Step 1 - Density of Material

Material is polycarbonate or PET G. Calculates will use density of PET G because it is heavier.

Material

Density

Source

Material

Density

Source

PET G

1.23 g/cm^3

Ultimate 3D Printing Material Properties Table (simplify3d.com)

Polycarbonate

1.22 g/cm^3

Polycarbonate (PC) Plastic: Properties, Uses, & Structure - Guide (specialchem.com)

Step 2 + 3 - Total surface area and Mass

Panel

SA (m^2)

Mass (SA x 1.23 x 1/8 inch thickness) (kg)

Panel

SA (m^2)

Mass (SA x 1.23 x 1/8 inch thickness) (kg)

Windshield

2.34912165

9.173907324

Headlight 1

0.0305137

0.2383272539

Headlight 2

0.0305137

0.2383272539

Door Windows

1.33092338

10.39517706

Total

 

20.04573889

Dynamics

An estimate was made.

Used mass properties features on SolidWorks on New S2020 Dynamics Assembly File.

Mass = ~47.8 kg x 2

Mass = 95.6

A more accurate attempt (Front vs. Rear Assembly Mass)

Strategy

  1. Inserted updated suspension and wheel geometry + old steering assembly

  2. got mass estimates from CAD of the front section vs. rear section

    1. Remember to multiply by 2 because this is a half car CAD model

  3. these are underestimate approximations

Front Dynamics Assembly

m = 19.61 kg x 2

m = 39.22 kg

 

Rear Dynamics Assembly

m = 33.51 kg x 2

m = 66.02 kg

 

Doors

Unable to find. Would need to ask @Geoffrey Liu