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Characteristic | MSXV - Reference | MSXVI - Goal |
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Vehicle Class | SOV - Bullet Style | SOV - Bullet Style |
Solar Array Area | 4m2 | 6m2 (Regs Dependent) |
Wheelbase | 1.9m | dictated by mass |
Track | 0.95m | between 0.85-0.75m |
Driving Motor | 2x Rear Motors | 1x Rear |
Overall Car Mass (w/ driver) | D: 300kg | F: >400kg | 300kg |
Loading Ratio (Front:Rear) | D: 40:60 | F: 25:75 | 40:60 +/- 10% |
Driver Sitting Position | legs fully extend, lean 25o back CG Xm from rear axle | legs fully extend, lean 25o back CG Xm from rear axle (-Xm) |
Driver Max Height | 34” (hip-head) Overall: 5' 9” | < 34” if anything Overall: 5' X” +/- 2”1” |
Chassis Type | FSAE Style - Chromoly Steel Tube | FSAE Style - Chromoly Steel Tube |
Battery Enclosure Volume | 720 x 394 x 245 (LWH) | 2x Potentially |
Battery Enclosure Location | Directly behind driver, inline with rear axle | please be accessible (HW)
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Overall Bounding Box |
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Avoiding drastic changes from MS15 to promote iterative improvements, build off existing knowledge base, and use MS15 as relevant inspiration for design
Dynamics takes priority as vehicle performance & design is greatly impacted by dynamic systems; exteriors is critical to vehicle efficiency
Space Claim System Priority List: Wheels, Suspension, motor, steering, battery, chassis, interiors, brakes, exteriors (consolidate with hardware whenever possible)
Compare and contrast to wsc regs
Mostly locked locations before reading week - Oct 14, revise in accordance with regs - around End of October
General
CAD Origin and XYZ directions
Master Assembly origin
If axis direction isn’t default, create a template New Part file on Bild
Axis direction is up to dynamics for calcs preference
Metric/ Imperial
Conclusion: Overall design in metric, critical fasteners and holes imperial only
Overall Car Mass → Look into the weight of competitors from ASC2024
Average for: SOVs, SOVs that qualified, SOVs that did well in FSGP & ASC
Occupant Cell
Driver height maximum discussion as it also leads into aerodynamic drag
if driver height reduced, aerodynamic performance optimized
if driver height increased, more people can drive
Suspension & Motor
Motor controller Space Claim
Requires airflow, 100% waterproof (not in the path of any water ingress or perfectly sealed), less then 3ft from motor, accessible when roof is up
parking brake opposite side of motor
Rear suspension: very similar to MS15
Steering
targeting ackerman steering, therefore volume in front of the upright is free game
Battery Structures
Battery box centred along right plane to balance sprung mass
Aiming to be located in front of the driver
Should still be protected by chassis tubes
Dictated by exteriors for final position
Action Items for Next Meeting
Driver selection, max height, dimension collection, location of driver along wheelbase
Wheelbase track:
Set track width 850-750mm
Distance between front plane and front contact patch
Suspension:
More accurate approximation of RSU
Width constraint on FSU
Steering: Accurate approximation for linkage volume
battery box
Lock in whether located in the front or the rear
Width is constrained by distance between suspension arms minus 2x Tube Thickness
Exteriors:
total area of array panel in reference to MS15
Meeting Notes - Sept 28 2024
Internals: driver selection 5' 9” 2025
Regs hopefullyDynamics: Double wishbone & ackerman steering
Battery: 1 enclosure with one smaller for HW
Exteriors: potential to change angle of attack, dependent of system location
General
Locked: Origin Location, Axis direction
Will be making Master Assemblies on Bild this week
Still waiting on 2025 & 2026 regs
Mass of the Car + Driver is a strict 300kg
Average mass of the FSGP top 10: 302.2kg
Average mass of ASC teams: 290.17kg
Average mass of ASC teams with >1000mile: 272.92kg
Occupant Cell:
Still discussing location of driver wrt to front wheel
Why move the driver forward?
Since the roof panel is narrower at the front of the car & the canopy takes away from precious array area, to optimize solar array area the goal is to move the canopy further towards the front of the car
Considerations to egress direction change ongoing (out the top or no change)
Option #1: no change (Driver hips = 1.25m from front wheel)
Pedal compartment unaffected by FSU hardpoints
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Option #2: Move slightly (Driver Hips < 1.2m from front wheel)
Pedal compartment within FSU hardpoints, creating tight working space during assembly & tuning with tight packing for dynamics systems
Option #3: Rivian is awesome (driver hips < 1m from front wheel)
Rivian Reference:
Can allow for much easier accessibility to the battery box with a side access panel and rails to easily remove enclosure for maintenance
Drivers feet in line with front “axle”, very tightly packed front compartment during assembly
Can introduce significant weight to the car
Exteriors:
angle of attack? nose compartment free game
Canopy elongation for better aero performance (provide ref.)
Main design constraint for space is solar area & tail cantilever
Battery
Referencing MS15 enclosure dimensions
refer to rivian concept
Suspension:
100% double wishbone
Current suspension dimensions are in line with jens referral
Richard Wang Winters Xia Please provide sources
Created parametric hardpoint frame
Potential to reinvest into upside down trapezoid hardpoint config
RSU no architectural changes expect maybe a bellcrank, pending
Action Item: Proper dimensions for next space claim
Steering
Due to decision to go ackerman & looking into moving the driver forward, the steering linkage is to be above FSU
Rough nodal to be devised for next space claim to accurately determine allocated volume
Over-exaggeration of tire angles to prevent interference
Brakes:
^ see occupant notes
Action Items for next space claim
Track Lock at 0.85m
Battery box location & hardpoint mapping
Finalize general location for dynamics hardpoints
Space Claim V2
Legend: purple = wheels, green = suspension, grey = steering, red = battery
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