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GENERATIVE DESIGN EXAMPLES & REFER

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“Jacobs expects that using Generative

Design will shorten design time by 20% and

produce parts which are incredibly

lightweight, resulting in significant fuel

savings.”

Jesse Craft

Senior Engineer

Jacobs Engineering

Jacobs Engineering is designing the

next-generation spacesuit for NASA using PTC’s

Generative Design solution

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JACOBS ENGINEERING – PLSS

Background: Jacobs is looking to reduce weight on structural components in

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JACOBS ENGINEERING – PLSS O2 TANK BRACKET

Part Description: Bracket to secure one end of O2 tank to PLSS subframe

Stated Customer Objective(s): Optimize for strength while minimizing mass, maintain a 1.5x safety factor to yield, 2.0x to ultimate

Primary Business Case Driver: Reduced weight, resulting in fuel savings during launch

Secondary Business Case Driver: Increased design productivity

amongst structural designers; frequent changes in PLSS mean rapid design iterations necessary

Load Case(s): Must withstand 18.5 g’s in all ordinate directions Preferred Material: Titanium (950 MPa ultimate, 860 MPa yield)

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JACOBS ENGINEERING – PLSS O2 TANK BRACKET

Problem Setup: In Creo 7, created design space from available volume within

PLSS; applied loads and constraints in GTO, set target mass to 0.3 lbm; created

BREP from generative result

BREP

Reconstruction Generative

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JACOBS ENGINEERING – PLSS O2 TANK BRACKET

Generative Design Original Design

Weight Reduction: 21%

Original

Generative

Weight

0.387 lb

0.306 lb

Safety Factor 6.8

3.1

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JACOBS ENGINEERING – PLSS CO2 SENSOR BRACKET

Part Description: Bracket to secure two CO2 sensors to the PLSS subframe

Stated Customer Objective(s): Optimize for strength while minimizing mass, maintain a 1.5x safety factor to yield, 2.0x to ultimate

Primary Business Case Driver: Reduced weight, resulting in fuel savings during launch

Secondary Business Case Driver: Increased design productivity

amongst structural designers; frequent changes in PLSS mean rapid design iterations necessary

Load Case(s): Must withstand 18.5 g’s in all ordinate directions Preferred Material: Titanium (950 MPa ultimate, 860 MPa yield)

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JACOBS ENGINEERING – PLSS CO2 SENSOR BRACKET

Problem Setup: In Creo 7, created design space from available volume within

PLSS; applied loads and constraints in GENERATE, set target mass to 1.10 lbm

Original Design Design Space Design Space + CO2 Sensors

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JACOBS ENGINEERING – PLSS CO2 SENSOR BRACKET

Generative Design Original Design

Weight Reduction: 20%

Peak Stress Reduction: 73%

Original

Generative

Weight

1.22 lb

1.01 lb

Max Stress

66.1 MPa

18.3 Mpa

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JACOBS ENGINEERING – PLSS CO2 SENSOR BRACKET

Additional Design Variants:

Mesostructure Surface Texturing

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“Generative design has the potential

to absolutely transform the

transportation industry as it seeks to

improve fuel economy through

aggressive weight reduction.”

Kevin McClintock

Senior Consultant

Volvo Group N.A.

Volvo Group is working on making

long-haul freight haulers

hyper-efficient by utilizing PTC’s Generative

Design solution

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VOLVO GROUP

Background: Volvo Group is engaged in the

SuperTruck project, a five-year challenge by

the U.S. Department of Energy to create a

truck that improves freight efficiency by 50% in

SuperTruck I, increasing to 120% for SuperTruck

II. For the latter, they needed to reduce

weight of the entire vehicle by an additional

2500 kg. Since weight savings forward of the

front axle are especially critical, several

structural components near the front of the

engine were considered.

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or

implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States

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VOLVO GROUP – SUPER TRUCK

Part Description: Forward engine mount

Stated Customer Objective(s): Since the part is forward of the front axle, weight savings is more valuable than in other parts of the vehicle; original cast iron part designed 17 years ago and still in production

Primary Business Case Driver: Decrease weight of original design, while achieving equal or better strength; also

wanted to improve upon a second version that was

designed by Penn State University during a year-long paid collaborative project

Secondary Business Case Driver: Increased design

productivity amongst structural designers; frequent changes in the engine mean rapid design iterations necessary

Load Case(s): Provided by Volvo Preferred Material: Cast aluminum

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Problem Setup: In Creo 7, created design space from available volume within

the engine, including all mounting points and neighboring components, some of

which you need air gap to prevent heat transfer; applied loads and constraints

in GENERATE, set various mass targets, aiming for around 10-12 lbm

VOLVO GROUP – SUPER TRUCK

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Example Design Variants:

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Final Result: Varied element resolution to force fewer, larger beams and struts to

be created since part will be investment cast; combined result with several

parametric features (mounting locations, bosses for fan ring mount, etc)

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Penn State Design Original Design

Variant Material Weight

(kg) Max Disp(mm) Max Stress (MPa) Comments

Original Design Iron (cast) 20.36 3.5 1393 Stress is 4.3x yield PSU Design Iron (cast) 11.86 2.6 1255 Stress is 3.9x yield Generative Design Al 356 (cast) 5.00 0.85 250 Stress is 1.5x yield

VOLVO GROUP – SUPER TRUCK

Final Generative Design

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VOLVO GROUP – SUPER TRUCK

Part Description: Fan motor mount

Stated Customer Objective(s): Current belt-driven fan clutch was being replaced with new fully variable electric motor, requiring a new mount; preliminary design was a three-piece sub-assembly; goal was to simplify to a single part Primary Business Case Driver: Design brand new part, improving upon weight and stiffness of preliminary sub-assembly, with reduced complexity and fastener count Secondary Business Case Driver: Increased design

productivity amongst structural designers; frequent changes in the engine mean rapid design iterations necessary

Load Case(s): Provided by Volvo

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Problem Setup: In Creo 7, created design space from available volume within

the engine, including all mounting points and neighboring components, as well

as the motor itself; applied loads and constraints in GENERATE, set various mass

targets, aiming for around 1 kg

VOLVO GROUP – SUPER TRUCK

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Example Design Variants:

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Final Result: Optimized for machining; exceeds target safety factor; lighter

weight than three-piece original design

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Original Multi-Part Design

Variant Material Weight (kg) Max Stress (MPa) Comments

Original Design AL6061 2.45 153 MPa Stress is 0.55x yield Generative Design AL6061 1.06 101 MPa Stress is 0.38x yield

VOLVO GROUP – SUPER TRUCK

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VOLVO GROUP – SUPER TRUCK

“Generative design of the forward engine mount, fan mount and bridge bracket (not

shown) resulted in a net weight savings of 34 kg, which accounts for 1.34% of the whole vehicle target mass reduction of 2500 kg. Imagine if

we’d had generative design when the platform was originally created...”

Kevin McClintock Design Consultant

References

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