Download Ram Racing - Colorado State University College of Engineering

Project Overview
• Primary Goal
–Design and build a working electric
vehicle
• Accelerated design cycle
–Modification of previous designs
Project Overview
• 1st electric vehicle for Ram Racing
– Create the platform for future years of Ram Racing
to iterate on
• Integration of electrical and mechanical
engineers
– Adds expertise of electrical systems which will
allow addition of more complex systems like:
• Regenerative braking
• The use of high voltage systems
Background
• FSAE is the largest international competition
involving engineering and automotive design
• FSAE competition is comprised of 7 scored
events
Static Events include: Dynamic Events include:
• Cost report
• Design Judging
• Presentation
•
•
•
•
Acceleration
Skidpad
Autocross
Endurance
Background
• Progression of cars
Photo courtesy: Ram Racing
Photo courtesy: Ram Racing
2013 CSU FSAE RR13
Photo courtesy: Ram Racing
2007 Ram Racing FSAE RR07
2011 CSU FSAE RR11
Photo courtesy: Ram Racing
2012 CSU FSAE RR12
Design Constraints
Constraint
Method of Measurement
Limits
Driving
Factor
Wheelbase
Length in inches: from the centerline of front to rear
tires
>60in.
FSAE Rule
T2.3
Track Width
Width in inches: from the centerline of side to side
tires
>75% front track
to rear track
FSAE Rule
T2.4
Power Output
Kilowatts: Drawn from high voltage battery
<80kW
FSAE Rule
EV2.2
High Voltage
Battery Pack
Roll Plane
Volts: overall voltage from any two points
300 V DC Max
FSAE Rule
EV1.1.2
Measured by tangent line between Main and Front
Roll Hoops
2in, min
clearance to
driver helmet
FSAE Rule
T3.10.3
Suspension
Inches of bounce and jounce
1in in both
directions, min
FSAE Rule
T6.1
Battery Pack
Pack must withstand external loading
FSAE Rule
AF4.8.2
Safety
Determined by Electrical safety officers
Determined by Technical Inspectors at FSAE
For Car safety to prevent Serious injury or death
20g long.
20g lat
20g vert
0
FSAE Rules/
Team Driven
Design Objectives
Objective
Priority
Rating
5-Highest
1-Lowest
Method of
Measurement
(Theoretical)
Method of
Measurement
(Actual)
Objective
Direction
Target
Battery Pack
Capacity
4
Hand calculations,
lap simulations
Endurance
simulation at test site
increase
Battery Pack
Mass
3
Spec Sheet with
hand calculations
Scale
decrease
Lap times:
Autocross
1
Lap simulations
Vehicle testing
details TBD
decrease
+10% of
endurance
distance
<140lbs
Compared to
other FSAE EV
teams batteries
< 1min 20sec from
the Michigan 2013
track layout
Endurance
Completion
5
Lap simulations
22km endurance test
increase
Light Weight
1
Hand calculations
Scale
decrease
+10% of
endurance
distance
<700lbs w/out
driver
Design Summary
• Due to the complications of integrating an
electric drivetrain, the team has decided that
getting the car done early is the biggest
concern
– Getting the car done earlier will allow for more
testing time
– The electrical system will be tuned primarily based
off of driver feel
Final Concept
Image: Ram Racing
• Function
Final Concept
– Main structure
– Protects driver
– Transmits loads
• Feasibility
– Modeling in CAD
– Installed torsional stiffness test
• DFX
Image: Ram Racing
– Manufacture
– Packaging
– Safety
• Details
– FEA stiffness: 998 lb-ft/deg
– 17% correction factor (overestimate):
828 lb-ft/deg
– Mass (est.): 90.7 lbs
• Tubes: 83.7 lbs
• Filler Rod: 2 lbs
• Tabs: 5lbs
Image: Ram Racing
Units
(Deg)
Final Concept (FMEA)
Potential
Failure Mode
Potential
Effect(s) of
Failure
S
E
V
Potential Cause(s)/Mechanism(s)
of Failure
O
C
C
Current Design
Controls
D
E
T
R
P
N
Recommend Actions
1
Chassis
Primary
Structure
Weld Failure
Disabled
Vehicle,
Driver Injury,
Loss of
Control
10
Bad Weld Quality
6
Visual
Inspection
4
240
100% Inspect All
Chassis Welds
2
Chassis
Secondary
Structure
Motor
Support
Failure
Driver Injury,
Damage to
other
systems
10
Bad Weld Quality, Incorrect
Geometry
6
Visual
Inspection
4
240
100% Inspect All
Chassis Welds
Tube Failure
Loss of
Stiffness,
Damage to
Other
Systems
6
Undersize Wall Thickness in Tube
4
Manufacturer
Certifications,
Visual
Inspection
7
168
100% Inpsect all
Chassis Tubes Before
Welding
Tab Failure
Damage to
Other
Systems,
Loss of
Control
7
Bad Weld Quality, Incorrect
Geometry
6
Visual
Inspection
4
168
100% Inspect All
Chassis Welds
2
Visual
Inspection,
Manufacturer
Certifications,
Additional
Battery
Containment
5
100
100% Inspect All
Chassis Welds
#
Item and
Function
3
4
5
Chassis
Primary
Structure
Chassis
Secondary
Structure
Chassis
Tertiary
Structure
Battery
Support
Failure
Driver Injury,
Diasbled
Vehicle
10
Bad Weld Quality, Improper
Support
Final Concept (Budget)
Chassis Budget
Cost
Source
Donation?
Chassis Tubes and Profiling
$2,900
Cartesian VR3
No
Remachining Fixture Plates
$500
Woodward
Yes
Fixturing Stock
$400
McMaster
No
Fasteners
$100
Suburban Bolt
No
Welding Filler
$100
Arc-Zone
No
Tab Stock
$100
Online Metals
No
Total:
$6,600
Cost After Donations:
$3,600
Final Concept
•
Function
– Keep tires in contact with pavement
– Keep tires in condition for optimum
accelerations
•
•
– Manufacture
– Reliability
– Performance
Feasibility
– Modeling in CAD/FEA
– Optimum Kinematics Analysis
Image: Ram Racing
Creo Solid Model
DFX
•
Accelerated Design Cycle
– Adaptation of design features from last 3
years
Image: Ram Racing
Optimum K Kinematics Model
Final Concept (FMEA)
#
Item and
Function
Potential Failure
Mode
Potential
Effect(s) of
Failure
S
E
V
Potential
Cause(s)/Mechanism(s) of
Failure
O
C
C
Current
Design
Controls
D
E
T
R
P
N
Recommend
Actions
1
Outer
Suspension
Ends
Stress Concentration
in Bending
Damage to
other systems,
Loss of control
10
Manufacturing Error
1
Visual
Inspection
2
20
Inspection by
recipiant
2
Uprights
Stress Concentration
in Bending
Damage to
other systems,
Loss of control
8
Manufacturing Error
2
Visual
Inspection
7
112
Inspection by
recipiant
Panel Delamination
Damage to
other systems,
Loss of control
8
Manufacturing Error
1
Visual
Inspection
6
48
None
10
Incorrect Geometry
1
Pre-testing
Visual
Inspection
5
50
Pre and PostTesting
Inspection
10
Improper Bonding Procedure,
Insifficient Bonding Area
4
Visual
Inspection
7
280
Tighter Control
of layup
process
3
Rockers
4
Carbon Tubes
Buckling/Bending
Damage to
other systems,
Loss of control
5
Pull/Push Rod
Tubes & Aarm Tubes
Adhesive Failure in
Shear
Damage to
other systems,
Loss of control
Final Concept (Budget)
Suspension Budget
Brake Discs
Brake Pads
Brake Calipers
Bearings (spindle)
Bearings (rod ends)
Carbon tubes
Cost
$200
$75
$150
$150
$400
$200
Source
In house
In house
In house
SKF
Aurora
In house
Donation?
No
No
No
No
No
No
Stock
Tires
Dampers
$200
$170 x 4
$1,720
Metal Distributor
Hoosier
In house
No
No
No
Springs
$250
In house
No
Total:
$9,025
Cost After Donations:
$1,430
Final Concept
• Function:
– Transfers Torque to rear wheels
– Accelerates car
• Feasability:
– Modeling in CAD
– FEA analysis
• DFX:
– Efficiency
– Reliability
– Packaging
Image: Ram Racing
• Details:
–
–
–
–
Torque: 210 Nm
Chain pull 6700N
4:1 gear ratio
Up to 80% Torque bias to one wheel:
624 NM
Image: Ram Racing
Final Concept (FMEA)
#
Item and
Function
Potential
Failure Mode
Potential
Effect(s) of
Failure
S
E
V
Potential Cause(s)/Mechanism(s)
of Failure
O
C
C
Current Design
Controls
D
E
T
R
P
N
Recommend
Actions
1
Half Shaft
Torsional
Shear
Disabled
Vehicle
8
Poor design, Machining
Imperfections
4
FEA, Previous
cars'
Performance
9
288
FEA, Stronger
Spares
2
Chain
Elongation,
Break
Disabled
Vehicle
8
Improper Maintenance/tensioning
2
Professional
Help, Math
6
96
Spare Sprockets,
Spare Chain
3
Differential
Mounts
Fatigue,
Bending,
Shear
Disabled
Vehicle
8
Poor design, Machining
Imperfections
3
FEA
7
168
Spare Mounts,
Material
Evaluation
4
Motor
Mounts
Fatigue,
Shear
Disabled
Vehicle, Driver
Injury
10
Poor design, Machining
Imperfections
3
FEA
7
210
Spare Mounts,
Material
Evaluation
Oil Starvation
Disabled
vehicle, Motor
Failure
2
Specialty
Pumps,
Professional
Help
32
Monitor Pumps
Closely, Safety
Shutoff
5
Motor
Cooling
8
Improper Flow Rate, Pump Failure
2
Final Concept (Budget)
Drivetrain Budget
Cost
Source
Donation?
Motor
$9,000.00
Remy, Inc
Yes
Differential
Inboard Tripod
Carriers
$1,000.00
HPF Performance
No
$370.00
RCV
No
Tripods
$140.00
RCV
No
Cooling Pumps
$1,000
Meziere
Yes
Half Shaft Stock
$300.00
Metal Distributors
No
Aluminum Mount
Stock
$200.00
Metal Distributors
No
Chain
$60.00
Ebay
No
Sprockets
$120.00
Sprocket Specialists
No
Total
$12,190.00
Cost After Donations
$2,190.00
Final Concept
• Function
-Drivetrain power
• Feasibility
– Modeling in CAD
– Circuit schematics
• DFX
Image: Ram Racing
– Packaging
– Safety
• Details
– 72S2P battery back
– 300Vdc max, 266Vdc
nom.
– Capable of 375Adc
continuous
– Safe under failure
– Weight: Est 104 lbs
– 7.5kW hrs
Image: Ram Racing
Final Concept (FMEA)
#
Item and Function
Potential Failure
Mode
Potential Effect(s)
of Failure
S
E
V
Potential Cause(s)/Mechanism(s) of
Failure
O
C
C
Current Design Controls
D
E
T
R
P
N
Recommend Actions
1
Battery Cell for
energy storage
Single cell
failure
Higher chance
of failure in
parallel cell
counterpart
2
Neglect, exceeding rated
specifications, poor cell
construction
3
Battery management
system monitoring
2
12
Handle with care,
operate within
specifications
2
Battery
Management
System for
monitoring cells
Voltage,
Current, or
Temperature
sensing failure
of 25% of cells
Fire, cell abuse,
Estimation of
sensed
parameters
(done
automatically
by BMS)
10
Exceed lifetime, bad
soldering, extreme vibration
2
Visual inspection,
isolate cell boards
from vibration along
with cells
7
140
Inspect all solder
work
3
High voltage
controller for
controlling the
motor
Control system
failure
Vehicle
shutdown
8
Misuse/neglect
1
Care is to be taken
with the controller
2
16
Handle with care,
operate within
specifications
4
Battery Cell for
energy storage
Two parallel cell
failure
Sudden loss of
all power
8
Neglect, exceeding rated
specifications, poor cell
construction
2
Battery management
system monitoring
2
32
Handle with care,
operate within
specifications
5
High voltage
controller for
controlling the
motor
HV cable
disconnection
Driver injury,
total loss of
power, fire
10
Improper torque for
connection
2
Check all torque
specifications
120
Check torque
applied to
connection point
6
Final Concept
•Function
–
–
–
Technical Inspection
Safety shutdown circuitry
Power various sensors
•Feasibility
– Circuit schematics
simulations
– Test and retest circuits for
faults
•DFX
–
–
Build/wire circuits
Safety
Image:
Ram Racing
Final Concept (FMEA)
#
Item and
Function
Potential
Failure Mode
Potential
Effect(s) of
Failure
S
E
V
Potential
Cause(s)/Mechanism(s) of
Failure
O
C
C
Current Design
Controls
D
E
T
R
P
N
Recommend
Actions
1
Torque
Encoder
Accelerometer
Sensor Failure
Loss of Control
6
Sensor mounting error, loose
wire/connections
4
Visual
Inspection,
Sensor fault test
3
90
Tighten
connections, test
with multimeter
2
Brake Encoder
Brake
Sensor Failure
Loss of
Control,
6
Sensor mounting error, loose
wire/connections
4
Visual
Inspection,
Sensor fault test
3
90
Tighten
connections, test
with multimeter
3
Arduino Mega
Microcontrolle
r for low
voltage
controls
Programming/
Power Failure
Loss of
Control, Signal
error to motor
controller
5
Visual
Inspection,
Inspection of
programming
code,
144
Tighten
connections, test
with multimeter,
review program
for errors
4
Sensata Crash
Sensor
Sensor Failure
Driver Injury,
due to
improper shut
down of
tractive
system
5
Visual
Inspection,
Sensor fault test
150
Shake the sensor
to see if it opens
the circuit
5
Bender
Isometer
Insulation
Monitoring
Device
Tractive and
Grounded low
voltage system
desegregation/
Sensor fault
6
Visual
Inspection,
Manufacturer
Certifications,
Sensor fault test
360
Check with multimeter to see if
tractive and
grounded low
voltage systems
are isolated
Driver Injury,
Potential
shock
6
Loose connections, lose of power
10
Impact upon crash does not
activate sensor
10
No seperation between tractive
and grounded low voltage systems
4
3
6
Final Concept (Budget)
Controls Budget
Cost
Source
Donation?
HV Cables
$400
Yes
HV Controller
$5,250
Champlain Cable
Rinehart Motion
Systems
Batteries
$12,500
Part Sponser
Bus Bar
Batter Management
System
Torque/Brake
Encoder
Arduino Mega 2560n
M3
$250
Melasta
Storm Power
Components
$1,624
Elithion
No
$229 x 3
XT Racing
No
$28
Ardunio
Yes
Misc. Components
$500
Various
Mix
Total
$21,239
Cost After Donations
$20,311
No
No
Validation Plan
•Majority of parts for final
assembly or testing have been
ordered or are currently on hand
•Assembly ongoing through winter
break
Image: Ram Racing
Image: Ram Racing
Validation Plan
• Evaluation
–
CAD
–
Hand Calculations
–
Modified Ram Racing Designs
–
Road Testing
–
Simulation
•
–
Image: Ram Racing
Safety Circuit
Specific Component Testing
•
Impact Attenuator
•
Battery Cell
Image: Ram Racing
Term II Work-Plan
• Main Goals
– Finish manufacturing and assembly of vehicle
– Begin testing and data collection of vehicle
• Secondary Goals and Contingency
– Refine and fix any design flaws
– Rework on systems that fail, break, or do not
work as intended
• [1] SAE International. (2014, September 1). 2015 Formula SAE®
Rules [Online].
Available:http://www.fsaeonline.com/content/201516%20FSAE%20Rules%20revision%20in%20progress%20kz%208
3114.pdf