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Project Overview The Xiphias concept vehicle is an independent student effort to predict the evolution of performance automobiles in both their technical and creative elements. Our focus is to develop various automotive engineering projects and integrate them into a professional-grade design package. Through these projects, which include research in aerodynamics, support structures, and powertrain systems, we will create a product that is both beautiful and relevant to the future of cars.

design package engineering

chassis

aerodynamics

powertrain


Research Inspiration

Chassis Weight reduction is often a top priority for automotive developers-- and not just for supercars. Less mass means quicker acceleration, better cornering, and improved mileage. A car’s chassis is always one of its heaviest components, which makes it a prime candidate for weight reduction research.

University of Michigan Solar Car, Altair HyperWorks Success Stories, Michigan, USA

If you look at a typical chassis, you can tell that there’s a lot of excess bulk that doesn’t contribute to supporting the vehicle. But there’s just no way to get rid of small chunks here and there while still being able to manufacture such a complex object using today’s methods. That will all change in the coming years, however, with the advent of additive manufacturing and more sophisticated computer modeling tools.

“Optimising FEV BIW Architecture from a Styling Envelope”, Jesper Christensen, Coventry University, UK

Our approach is to combine software-based topology optimization and Finite Element Analysis to produce a chassis that weighs as little as 5-15% of the vehicle’s overall mass. We are likely to arrive at a chassis concept that is revolutionary in both its appearance and its function. Several static and dynamic loading tests will be conducted on the structure to demonstrate its safety and efficiency, and a 3D-printed model will accompany our other final deliverables in December 2013. The software packages enabling this research are available to us through the PACE program, of which Lehigh University is a partner institution. "An Integrated Optimization System for ANSYS Workbench Based on ACT", 2012 Automotive Simulation World Conference Manfred Fritsch. FE-DESIGN GmbH, Germany


Topology Optimization The first step of chassis development is to provide a computer program with a virtual model to work with. In our case, we will be using a solid model of the Xiphias concept’s whole interior, with spaces cut out where the drivetrain and occupant space would be. This represents all the possible space for the chassis that the computer program can decide to either keep or discard as it finds the optimal solution balancing weight with strength. We will be using part of the ANSYS 14.5 software package to conduct this stage of our research.

Finite Element Analysis Testing After the model has been optimized according to various loading conditions it might encounter while driving (such as accelerating, cornering, hitting a bump in the road, etc.), we will conduct a series of thorough F.E.A. tests to ensure that the chassis conforms to relevant IIHS safety standards.

Additive Manufacturing The only fabrication method that is even remotely suitable for producing a topologically-optimized car chassis is 3D printing. We will use processes similar to our exterior model for printing preparation, and will present a 1:14 scale object in our final round of deliverables.

Selective Space Structures (tentative) One of A.M. technology’s greatest virtues is that it eliminates the notion that high geometric complexity necessitates high production costs/time. Large, solid objects can be reduced to crystal-lattice-like structures that preserve their overall shape but are made up of tiny, repeated geometric cells. These objects, mostly made up of empty space, might serve as an innovative solution to crumple zones in the event of a car crash. Not only would they be lightweight, but they might also have tremendous energy-absorption qualities that ultimately reduce the risk of passenger injuries and lessen damage sustained to the vehicle. We are currently in talks with netfabb GmbH (the software developer behind S.S.S.) to explore the possibility of adding this concept to our research.


Aerodynamics Wind resistance is one of the key forces fighting against high-performance vehicles. In order to ensure our concept’s relevance well into the future, we must demonstrate that we can minimize air drag while taking full advantage of downforce also produced. Such testing will take place in Lehigh University’s Packard Wind Tunnel Lab, which can accommodate a reasonably-scaled model and can simulate driving conditions at well above concept’s top speed.

Front Wheel Front Face Front Splitter Most of the Low, sharp face of the Well Inlet Vents Provide cooling for the front causes minimal brakes, front motors, disruption in airflow entering the car’s and batteries. underbody, allowing the diffuser in the back to function optimally.

oncoming air is redirected upward, adding extra downforce to the forward section of the vehicle.

Occupant Inlet Vent Turbulent air tumbles over the lip behind the hood and feeds into Air-Conditioning/ventilation for occupant space.

Front Wheel Well Outlet Vents Allow hotter air coming from the brakes, front motors, and batteries to escape.

Rear Deck Rear Wheel Inlet Vents Well Inlet Provide cooling Vents for the brakes, rear motors, and batteries.

Provide cooling for the brakes, reduce turbulent flow around sides of the vehicle.


Diffuser

Variable-Geometry Wing

Redirects air flowing beneath the car upward, simultaneously reducing drag and producing extra downforce. Average geometry is close to optimal diffuser rake angle (14 degrees).

Produces a downforce effect similar to giant spoilers mounted on racecars, except without disrupting the surrounding airflow. Maximizes effect by wrapping the wing around the diffuser interior, possibly producing a mutually-beneficial configuration.

Rear Outlet Vents Allow hot air coming from the rear motors and batteries to escape.

Winglet

Longitudinal Fence

Reduces downwash vortex at wingtip.

Separates turbulent wheel well airflow from smooth laminar diffuser airflow, minimizing disruption to underbody aerodynamics functionality.


Powertrain The idea of an all-electric vehicle is no longer perceived as unattainable or wildly futuristic. Instead, it is an increasingly feasible solution that addresses the modern world's needs and even improves upon conventional powertrains in many ways. Batter-electric vehicles are highly efficient, produce zero tailpipe emissions, and require minimal amounts of drivetrain maintenance. Electric motors can outperform their conventional counterparts (Internal Combusion Engines, or ICE, for short) in virtually any field. The goal of our powertrain research is to predict the optimal combination of all-electric components ten years in the future by examining the functionality of these parts and extrapolating current trends.

Battery System Energy storage is perhaps the largest obstacle for mass adoption of electric vehicles. The goal of energy storage is to achieve the highest amount of sustained power in the lightest, most efficient, and most quickly rechargeable package possible. Battery life can be extended with a proper management system that monitors thermal activity and charge state. Our goal is to gather knowledge on "superlative cell" chemistry and optimize battery pack geometry and layout accordingly.


Motor System Permanent Magnet (PM) motors are compact, have a high power density, and produce large torque. Two pairs PM motors are housed at both the front and rear of our car. Each motor will be independently controlled, allowing for torque vectoring. We will be analyzing thermal conditions and optimizing motor housing design.

Torque Vectoring By assigning an independent electric motor to each wheel, engineers can control the precise amount of torque being sent to each wheel. This greatly improves traction and maximizes a car's cornering abilities. When harmonized with instantaneous torque at any RPM and a low center of gravity, torque vectoring promises exciting developments in driving experience in the future.

Computer Modeling We will use modeling and simulation programs throughout our powertrain research and development process. Our method of powertrain system modeling will allow us to create hierarchical subsystems that will then be simulated to test for energy management and optimal performance.


Design Our concept’s main inspiration derives from naturally-driven design. Predatory fish, in particular, embody the agility and efficiency we aim to emulate. Xiphias comes from the Latin name for swordfish, an iconic creature that ranks among the fastest inhabitants of the ocean. Only its most essential features have remained after countless years of evolution. Its fundamental beauty has arisen from the stripping away of excess elements. We aim to evoke this same principle by creating an aerodynamically efficient and highly emotional design. Therefore, our concept is a passionate, yet relevant design exercise for a small team of automotive developers who are capable of setting themselves apart from all others.

Project Progress

concept generation

design development [ 2D workflow ]

Surface Construction

free-form surface modeling [ 3D workflow ]

model refinement

Surface Continuity

visualization objective & functional & desirable final refinement design package

3D Print Preparation


Spline Cage

Class-A Surface

1:8 Scale Model - Fabrication in progress

1:14 Scale Model


3D Visualization with Luxion Keyshot

Each of our engineering projects needs a high-quality model that meets industry standards and remains consistent throughout iterations. Starting with a set of rough blueprints, we were able to construct a "spline cage," or a set of curves hanging in 3D space that defines the outline of the car. Then those curves were refined and filled in with surfaces. But this gave us only an infinitely thin sheet that resembled a car rather than a solid object that could be 3D printed. Therefore, we added thickness to the surface model and then translated it from a 'math language' virtual object (NURBS) to a mesh of tiny triangles (STL) that a 3D printer could understand. The final result is a 1:8 scale physical object (and its virtual counterpart) on which we can run wind tunnel tests, optimize a chassis structure, examine driver ergonomics, and design an advanced powertrain system.


Team James Suh

Penn Scott

Director & Creator Product Design Lehigh ‘14

Project Manager & Co-creator IDEAS Lehigh ‘13

Project: Design Major Responsibilities: creative direction, concept creation & development, design development, portfolio & presentation materials, model fabrication, graphic design, coordinate with engineering projects, recruitment, final decisions on all aspects of the vehicle

Project: Model & Chassis Major Responsibilities: oversee all engineering projects and technical development, coordinate with concept development, Class-A NURBS modeling, FEA/topology optimization, 3D printing, external project relations, written materials

Miguel Roman

Robert Vargo

Design Engineer Chemical Engineering & Product Design Lehigh ‘13

Engineer Mechanical Engineering Lehigh ‘14

Project: Powertrain Major Responsibilities: powertrain research, thermal efficiency analysis, powertrain modeling, design direction, fabrication and graphic design assistance, website design, social media

Project: Chassis Major Responsibilities: chassis engineering specifications, chassis and powertrain research, wind tunnel setup, testing, and data collection

Max Miller

Marcus Risland

Aerodynamicist Mechanical Engineering Lehigh ‘14

Business Specialist Finance Lehigh ‘14

Project: Aerodynamics Major Responsibilities: aerodynamics research, wind tunnel setup, testing, and data collection, aerodynamic redesign

Project: Business Model Major Responsibilities: business model lead, funding strategy, external project relations


Acknowledgements advisors

faculty

administration

Wes Heiss

Brian Slocum

Alice Gast

Product design

Art, Architecture & Design

President

Edmund Webb III

Bill Maroun

Pat Farrell

Mechanical Engineering

Mechanical Engineering

Provost

Bill Best

Jason Travers

Van Dobson

Electrical Engineering

Art, Architecture & Design

Associate vice president

Terry Hart

Alan Snyder

Mechanical Engineering

Vice president, Associate provost

Joachim Grenestedt

Joe Kender

Mechanical Engineering

Vice president, Advancement

Nik Nikolov Art, Architecture & Design

David Angstadt Mechanical Engineering


Thank you

All works Š by the Xiphias Project team Do not reproduce without the expressed written consent of the management contact: suhjames24 @ gmail.com


Xiphias project | summer portfolio 2013