Fundamentals of Vehicle DesignDr. Shirish P Patil &Dr. Kamarul Tawi

Course ObjectivesUnderstand vehicle manufacturing organizationUnderstand vehicle development processUnderstand vehicle systems and attributes (properties)Learn to set performance specifications for a new vehicleUnderstand system/component contribution towards vehicle performanceLearn to set specifications for system/component designLearn to design components to meet specifications

Course OutlineOverview of vehicle design processVehicle performance specificationsVehicle acceleration & powertrain design specificationVehicle deceleration & brake design specificationVehicle ride & chassis design specificationVehicle roll-over & chassis design specificationVehicle handling & chassis design specificationVehicle durability & chassis design specificationVehicle crash safety & body design specificationDesign of the suspension systemDesign of the steering systemDesign of the body/door system

Course ScheduleEvery Tuesday: classroom instruction (2 hours)Every Thursday: group project discussion (3 hours)Study time: approximately 4 hours/week

Evaluation CriteriaFinal written project report including weekly log of activities (40%)Final project presentation (15%)Mid-term project presentation (5%)Team participation & contribution (40%)

Team Participation & Contribution Evaluation

No.Performance CriteriaLevel 1Level 2Level 3Level 4Level 51.ContributionsDoes not provide ideas when participating in the group discussion.Rarely provides ideas when participating in the group discussion. Sometimes provides ideas when participating in the group discussion. A satisfactory group member who does what is required.Usually provides useful ideas when participating in the group discussion. A strong group member who tries hard.Routinely provides useful ideas when participating in the group discussion. A leader who contributes a lot of effort.2.Effort in Problem-solvingDoes not try to solve problems or help others solve problems. Lets others do the work.Rarely tries to solve problems or help others solve problems.Does not suggest or refine solutions, but is wiling to try out solutions suggested by others.Refines solutions suggested by othersActively looks for and suggests solutions to problems.3.AttitudeAlways publicly critical of the project or the work of other members of the group. Has negative attitude about the task(s).Is often publicly critical of the project or the work of other members of the group. Is often negative about the task(s).Is occasionally publicly critical of the project or the work of other members of the group. Usually has a positive attitude about the task(s).Is rarely publicly critical of the project or the work of others. Often has a positive attitude about the task(s).Is never publicly critical of the project or the work of others. Always has a positive attitude about the task(s)4.Participation and Working with OthersDoes not participate, listen to, shares with, and supports the efforts of others. Is not a good team player.Rarely participate, listens to, shares with, and supports the efforts of others. Often is not a good team player.Often participate, listens to, shares with, and supports the efforts of others, but sometimes is not a good team member.Usually participate, listens to, shares, with, and supports the efforts of others. Does not cause ripples in the group.Almost always participate, listens to, shares with, and supports the efforts of others. Tries to keep people working well together.

Project DescriptionEach team (5 students) will choose a passenger vehicle to be engineeredTeam will decide the performance specifications for the vehicleTeam will design the specifications for the powertrain/brake/suspension/body system so that vehicle specifications are satisfied

Requirements for the ReportList of specifications for cost, weight, acceleration, braking, ride, handling, roll-over, crash safety and durability. Method of setting each specificationDesign of powertrain system properties to meet acceleration specificationDesign of brake system properties to meet braking specificationDesign of suspension & steering system properties to meet ride, handling, roll-over and durability specificationDesign of body system properties to meet crash-safety specificationDesign of door system properties to meet door closing effort specification

Vehicle Classification

Vehicle TypeBody StylePower TrainSuspensionPassenger Car2D/3D/4D/5D UniBodyEngine: 1.0-3.0LTrans: 5spd/AutoDriveline: FWDFront: McPhersonRear: Multi-linkMPV4D/5D UniBodyEngine: > 2.0LTrans: AutoDriveline: FWDFront: McPhersonRear: Multi-linkSUV5D Unibody or Body on FrameEngine: 1.8-5.0 LTrans: AutoDriveline: FWD/RWD/AWDFront: McPherson/SLARear: Multi-link/Solid Axle

Luxury Car4D Unibody or Body on FrameEngine: >2.5 LTrans: AutoDriveline: FWD/RWDFront: SLARear: Multi-link

Sports Car2D/3D UnibodyEngine: >3.5 LTrans: 5SpdDriveline: RWDFront: McPhersonRear: Multi-linkPickup Truck2D/4D Body on FrameEngine: >2.5 LTrans: AutoDriveline: RWD/AWDFront: SLARear: Solid AxleCommercial Truck2D Body on FrameEngine: >5 LTrans: AutoDriveline: RWDFront: SLARear: Solid Axle

How to prepare vehicle specifications?Understand what your customer desiresUnderstand what your competition offersUnderstand government regulation

Team ExercisePick a vehicle you plan to designWrite vehicle specifications by studying 2 or more competition vehicles (study dealer specs., do internet search, etc.)

Cost SpecificationWhat is the intended selling price of the car?How many units do you plan to sell?Will you make any profit?

Weight SpecificationWhat is intended gross vehicle weight (GVW)?How many passengers?What is the luggage capacity?Weight distribution?

Geometry SpecificationWheelbase?Tread?Ground clearance?Tire size?

Acceleration Specification0 to 100 km/h in how many seconds?Engine torque/power?Transmission speed? Auto or Manual?

Braking SpecificationDeceleration level required?Stopping distance from 100 km/h?Dry surface/Wet surface?

Ride SpecificationDesired ride frequency?Desired passenger acceleration on an average road surface?

Roll-over Safety SpecificationWhat is the max lateral acceleration the vehicle will sustain?

Handling SpecificationMinimum turning radius?Understeer or oversteer?Steer gradient?

Durability SpecificationWhat is the desired life of a suspension component?

Crash Safety SpecificationWhat is the average deceleration experienced during frontal crash?

Organization of an AutomakerLeadershipVehicleEngineeringSales&MarketingManufacturing&AssemblyFinanceAfterSalesServiceDealerNetworkSuppliers

Concept to Customer ProcessCustomerRequirementsRegulationsVehicleProgramVehicleEngineeringManufacturing&AssemblySalesService

Organizational Responsibility

OrganizationResponsibilityExamplesCentral LeadershipRun the company profitablyProvide leadership for the futureProvide initiatives to buildEco-friendly carsFinanceRaise & provide funds to run operationsProvide loans to customers for purchasing vehiclesVehicle EngineeringEngineer the vehicle to meet customer specifications and regulatory requirementsDesign & test parts and vehicles to meet specs.Manufacturing & AssemblyManufacture parts & assemble vehiclesManufacture stamped body panels & engine castingsSales & MarketingGather customer specificationsSet customer wantsAfter Sales ServiceProvide after sales customer serviceEnsure availability of replacement partsDealer NetworkSell & service carsSuppliersManufacture parts & assemble systemsDesign/test/manufacture parts

Vehicle Development Organization

Product Engineering

OrganizationResponsibilityBody EngineeringDevelop exterior sheet metal and interior trim to meet engineering and cost specificationsChassis EngineeringDevelop suspension/steering/brake/frame system components to meet engineering and cost specificationsPowertrain EngineeringDevelop engine/transmission/driveline/fuel/exhaust system components to meet engineering and cost specificationsClimate Control EngineeringDevelop HVAC system components to meet engineering and cost specificationsElectrical & Electronic EngineeringDevelop electrical/electronics/entertainment system components to meet engineering and cost specifications

Vehicle Engineering

OrganizationResponsibilityPackage EngineeringEnsure all systems and components fit in the vehicleWeight EngineeringEnsure all systems and components meet weight spec.Safety EngineeringEnsure that the vehicle meet the regulatory safety spec.Vehicle DynamicsEnsure that the vehicle meet the regulatory/customer ride & handling spec.Durability EngineeringEnsure that the vehicle meet the customer durability specVehicle NVHEnsure that the vehicle meet the customer Noise, Vibration & Harshness spec.Prototype Planning/TestPlan & manage prototype builds and testing

Styling

OrganizationResponsibilityExterior StylingDevelop exterior sheet metal Class I (Styled) clay surfaceInterior StylingDevelop interior trim Class I (Styled) clay surface

Vehicle Development Process

Vehicle Development Process

ProcessOutcomeActivitiesExamplesPrepare Spec.Final vehicle, system & component spec. Hold customer clinics Benchmark vehicles Study regulations 0 to 100 kmph in 9 sec Investment cost < $ 500M no structural failure < 150,000 kmConcept EvaluationData required to make decisions Design feasibility studies Cost feasibility studies Is acceleration spec. possible? Is investment target possible?Program ApprovalGO or NO GO decision Program meeting

Prototype Design & TestingData required for 80% confidence in the design Part design Manufacturing & Assembly Testing CAD surface or solid with drawings soft tooled part & pilot plant assembly CAE/Lab/Proving Ground testingProduction Design & TestingData required for 99% confidence in the design Part design Manufacturing & Assembly Testing CAD surface or solid with drawings hard tooled part & plant assembly CAE/Lab/Proving Ground testingFix Problems before Launch100% confidence Final fixes by launch team

Vehicle Systems & Attributes

Function of Vehicle Systems

Vehicle SystemFunctionBody Provide durable attachment for other major systems Provide safe and pleasant seating environment for all passengers Protect passengers from crashesChassis Provide capability to steer the vehicle Provide capability to brake the vehicle safely Provide isolation between road and passengersPowertrain Provide capability to accelerate the vehicle by transferring torque to wheels Provide capability to control vehicle speed Meet regulatory exhaust requirementClimate Control Maintain comfortable temperature distribution for passengers Provide windshield defrost capabilityElectrical & Electronics Provide power supply where needed Provide desirable entertainment system Provide functional censors and controls

Vehicle Attributes

Vehicle AttributesDescriptionCostLowest production, assembly and distribution cost compared to competitive vehiclesWeightLowest curb weight compared to competitive vehicles in its weight classPackageBest use of the space to provide comfort and amenities to passengersSafety5* crash rating from the Federal Motor Vehicle Safety Standard (FMVSS)DynamicsBest ride & handling performance compared to competitive vehiclesDurabilityHighest reliability and high mileage durability compared to competitive vehiclesNVHLowest noise, vibration and harshness compared to competitive vehicles

*********