Wikispeed SGT01
NOTE- this article is flagged for re-title to "SGT01", for super grand touring 01.
Team Wikispeed has open sourced their first car! They agree with OSE, and the open source movement, that everyone will benefit faster when there are fewer barriers to innovation and collaboration.
It is important to note, however, that the STG01 is not the GVCS car. It was designed to compete in the Progressive Automotive X-prize, not to be made out of the common modular pieces of the GVCS. But the principles/processes are largely the same, and many of the control/interface systems can be identical.
Contents
- 1 Wikispeed STG01
- 1.1 CAD
- 1.2 Bill of Materials
- 1.2.1 Chassis
- 1.2.2 Engine Module
- 1.2.3 Engine Module Least Expensive
- 1.2.4 Engine Module More Power
- 1.2.5 Engine Module Frame
- 1.2.6 Suspension
- 1.2.7 Pedal Plate
- 1.2.8 Front Crush Zone
- 1.2.9 Rear Crush Zone
- 1.2.10 Side Crush Zone/Trunk
- 1.2.11 Body/Aeroshell
- 1.2.12 Body Top Mount Frame
- 1.2.13 Interior
- 1.2.14 Wikispeedlet
- 1.2.15 MT Shift Control
- 1.3 Chassis
- 1.4 Build Steps for Small Volume Scenarios
- 1.5 Build Steps for Volume Scenarios
Wikispeed STG01
CAD
The following CAD files are STEP 203's that were exported from the Alibre files Wikispeed uses.
Assembled Vehicle
Chassis Module
Bulkhead Plate
- Attaches to the front of the chassis
- Used to mount things like the brake cylinder
- File:Wikispeed SGT01 Bulkhead Plate.stp
Engine Module Frame
Floor Plate
- Attaches to the bottom of the chassis
- File:Wikispeed SGT01 Floor Plate.stp
Crush Structures
- Attaches to the front/rear of the chassis
- Serves as a sacrificial crumple zone in the event of a crash
- Used to mount things like headlights
- File:Wikispeed SGT01 Front Crush Structure.stp
- File:Wikispeed SGT01 Rear Crush Structure.stp
Interior Module
- This is the interior module as an aluminum tube frame
- File:Wikispeed SGT01 Interior Module Frame.stp
- This is the interior module as an aluminum bathtub
- File:Wikispeed SGT01 Interior Module.stp
Assembled Suspension
Suspension Components
- Tie Rod
- File:Wikispeed SGT01 Suspension Left Tie Rod.stp
- Lower Control Arm
- File:Wikispeed SGT01 Suspension Lower Control Arm.stp
- Hub pivot point
- File:Wikispeed SGT01 Suspension Lower Hub Pivot v2.stp
- mount plate
- This is what holds the suspension together and attaches it to the chassis
- File:Wikispeed SGT01 Suspension Mount Plate.stp
- strut mount
- File:Wikispeed SGT01 Suspension Strut Top Mount.stp
Body Frame
- This frame mounts any aerodynamic body to the chassis
- File:Wiklspeed SGT01 Body Module Mount Frame.stp
Bill of Materials
Chassis
~$434
- 4"x4"x.125" extruded square tube 6061-T6
- brake lines, 28'
- floor 78"x48"
Engine Module
~$8422 (from Honda Performance Development)
- GENERAL ASSY., CYLINDER BLOCK (DOT)
- GENERAL ASSY., CYLINDER HEAD
- WIRE HARNESS, ENGINE
- ALTERNATOR ASSY. (AHGA67) (MITSUBISHI)
- BRACKET, ALTERNATOR
- 4x4x.125" extruded square tube (140 feet?) 6061-T6
- camshaft, cam chain
- clutch - torque converter
- Catalytic Converter
- Injector Assy, Fuel
- Gasket Kit (engine, transmission, chain case)
- Intake Manifold
- Pump Assy, oil
- plug hole coil
- spool valve
- STARTER MOTOR ASSY(SM-71001)MITSUBA
- Throttle Body 1.8L
- ARM ASSY., ROCKER
- water hose (1.8l)
- water pump (1.8l)
- 5AT Transmission
- 5MT Transmission
- Radiator
- Radiator hose
- ECU 1.8L MT
Engine Module Least Expensive
~$5232 (Honda Performance Development)
- L15A crate engine
- L15A 5MT
- L15A ECU 5MT
- L15A ignition
- L15A key
- L15A engine harness
- L15A dash harness
- Radiator
- Radiator Fan+shroud+motor
- Radiator hose
Engine Module More Power
~$8815 (Honda Performance Development)
- Civic Type R crate engine
- Si 6MT
- Hondata ECU
- Civic Si ignition
- Civic Si key
- Civic Si engine harness
- Civic Si dash harness
Engine Module Frame
~$169 (for 2 units)
- 1.25x1.25x.125" 6061-T6 tube (34.4 feet?)
Suspension
~$4283 (for 4 units)
- Skunk2 Pro C
- 15x7 MOTEGI RACING SP10 HB
- 195/65R-15 Bridgestone Ecopia EP100
- .25" thick plate, 2'x2' 6061-T6
- strut top mount angle 6061-T6
- 3/8ths x24 grade 8 bolts
- 3/8ths x2 lock nuts
- 1" OD 3/8ths ID steel washers
- (Honda Performance Development)
- Front Knuckle
- Joint F. Ball Lower
- Bearing Assy, Front Hub
- Hub Assy, Front.
- Disk Fr Brake
- Caliper sub assembly, FR
- Pad Set, FR.
- knuckle bolts (BOLT, FLANGE (14X57)) (2)
- knuckle bolt nuts (NUT, SELF-LOCK (14MM)) (2)
- strut top mount nuts (NUT, FLANGE (10MM)) (3)
Pedal Plate
~$243
- steering column (summit racing)
- (Willwood)
- steering rack
- CMB-14-0010 master cylinder and pedal combo
- ABS block and proportioning valve: WIL-260-11179
- APS229 - Standard Motor Accelerator Pedal Sensors
Front Crush Zone
~$22
- 6x6x.125" 6061-T6 square tube (9.1 feet?)
Rear Crush Zone
~$19
- 6x6x.125" 6061-T6 square tube (7.75 feet?)
Side Crush Zone/Trunk
~$169 (for 2 units)
- 1.25x1.25x.125" 6061-T6 tube (34.4 feet?)
Body/Aeroshell
~$1107
- polycarbonate (US plastics) (4'x8' x 1/8" sheet)
- nida core honeycomb (NW composits) (4'x8' x 1/2" sheet)
- rivets
- (US Composits)
- 5.7oz Carbon Plain weeve (50" x 18 yards)
- epoxy (54 gal)
- hardner (18 gal)
- 10oz e-glass mat (50" x 18 yards)
- e-glass biaxial mat 1208 (50" x 18 yards)
Body Top Mount Frame
~$169 (for 2 units)
- 1.25x1.25x.125" 6061-T6 square tube (12.5 feet?)
Interior
~$823
- carpet 40"x6'
- Autoloc 3 point belt (2)
- (US Composits)
- 5.7oz carbon plain weeve (6)
- epoxy
- hardner
- 10oz e-glass mat (6)
- e-glass biaxial mat 1208 (6)
- (Summit Racing)
- GRT-687 GRANT RACING STEERING WHEEL
- SUM-800600 DIGITAL 6 GAUGE PANEL
- poly seat black 2100 series & cover combo (2)
- DUAL LOCK SLIDING SEAT BRCK PR (2)
- SUM-G1122 COVER & BRACKET KIT SINGLE
- CIP-19100 REPL MIRROR PAIR
- SUM-G2111 seat cover for G2100 seat (2)
Wikispeedlet
~$271
- 5-1577-4 3.93" STROKE 107 LB. 12 VDC LINEAR A (Surplus Center)
- 5-1577-B LINEAR ACTUATOR MOUNTING BRCKT (Surplus Center)
- Arduino Uno (Maker Shed)
- 12v to 5v converter
- Box, 12"x12"x4".
- PEDAL ASSY., ACCELERATOR (Summit Racing)
MT Shift Control
~$233
- 5-1577-4 3.93" STROKE 107 LB. 12 VDC LINEAR A
- 5-1577-B LINEAR ACTUATOR MOUNTING BRCKT
- Arduino Uno
- 12v to 5v converter
- Box, 12"x12"x4".
Chassis
The Wikispeed car(s) is always evolving, so it's best to start with a piece that hasn't significantly changed in a while. The basic chassis is nothing more than 4" square aluminum extrusion welded into a series of boxes. However, it has a 5-star crash equivalency rating. It is only around $550 in parts and those parts are commodities, so they can be overnighted pretty much anywhere in the world. All you need to build the chassis is an average sized garage, a saw to cut the aluminum, and a welder to fasten it together.
Illustrations are on the way.
BOM
- 4" x 1/8" thick square tube
- 120" long (x4)
- 40" long (x4)
- 12" long (x6)
- Yeah, that's it. That's all the frame is made out of :-)
Project Steps
- Cut aluminum tube to specified lengths
- The only location that needs to be measured
- The center vertical tube is 36" from the inside of the vertical tubes on the open end of the chassis and 72" from the inside of the vertical tubes on the closed end
- Other than that, everything lines up on obvious edges
From Joe's Notebook
For the aluminum, we use Coast aluminum over here, and order 500 lbs at a time in stock lengths. This lets us get a discount, and by always ordering whatever length they stock we avoid "cut fee's". For the build, it is ideal to have 3' on each side of parts we are working on. For the chassis, it's 4'x10, so 10'x16' is ideal. The total car, with body, is larger at 6.5'x14', so 12.5'x20' is ideal. It can be worked with far less, however, and I think the ultimate flow of work, when it is optimized, will be to manufacture these inside a shipping container "factory" that can be shipped to wherever the local demand might be.
The jig plates [specifications on the way] are a pre-requite for building the chassis...After each weld, the surface is grounded down (4" electric grinder, or, a coarse file and some hand work) so that the jig plate can be bolted back on flush. At the end, the jig plates are actually other modules- the roll bar mounts and the suspension plates, so they simply have the rest of their components bolted on and now there is a rolling chassis.
Using the jig plates and a 3/8ths centering punch, holes can be drilled to attach the frame to the jig with bolts, then the frame is tack welded, then the jig plates are removed and replaced one corner at a time while the frame is seem welded with the other jigs holding the chassis square as it is heated and cooled during the welding.
The current configuration requires 18.33 KW to bring its 1404 weight plus a 150 lb driver (EPA standard) through the UDDS city test, and 15.11 for the HWFET highway test. However, to meet the X Prize minimums (no-longer required but researched by the X Prize as acceptable minimums for mainstream market interest) our vehicles requires 31.1kw to go from 40mph to 65mph in less than 9 seconds. This is approximately 41.7hp. 50hp or larger gives us a safe target to determine in the drive-train meets our minimums. Please note the current 140hp engine module weighs about 700lbs. That includes fuel, emissions system, cooling system, axles, transmission, engine, engine electronics, data logging, battery, coolant, all fluids, 4 gallons of gas, aluminum engine module cradle.
For brakes, we've used OEM Honda parts and Willwood parts, each had advantages. Currently we are using OEM Honda (2006 civic 1.8l automatic) steering knuckles, bearings, hub carriers, brake rotors, and calipers. Currently we are using a Willwood pedal and master cylinder combo. For steering, currently we are using a honda s2000 steering rack. In past we have used a 2006 civic steering rack. There are pros and cons to each.
...you would need $540 of skunk2 suspension system(normally $1799 but we get a great discount) and some suspension and braking assemblies from a 2006+ 1.8 automatic honda civic. You may be able to get those at a good price from a wrecking yard...
Build Steps for Small Volume Scenarios
Rolling Chassis
Chassis
- receive in mail or cut and weld on location. http://www.youtube.com/watch?v=YvN8ZF1-ogY&context=C4d5a23fADvjVQa1PpcFNIheMStKChcQuO9z0Bcs9fLnn3W5EWwXM=
- cut and weld on location requires bandsaw set to cut square, jig plates (can be mailed or CNC'd locally), speed square and accurate 48" tape measure with 1/16th" or smaller tick marks.
- If made on site, chassis must then be drilled, requires centering punch, hammer, centering 3/8ths drill bit and drill (drill press or coal drill preferred).
Suspension Module
- 12 strut top nuts
- 4 Skunk2 Pro C adjustable struts - $1100 - [1]
- 4 brake calipers/pads/bolts
- 8 19mm bolts for knuckles on strut
- 4 lower knuckle ball joints/fasteners/lock nuts
- 32 grade 8 bolts/lock nuts to attach plate to chassis
- 20 lug nuts
- receive in mail or CNC on location.
- Assemble
- compare to photos for test.
- bolt on to car
- recieve grade 8, 3/8" bolts, washers, and lock nuts
- 9/16ths wrench and socket with ratchet required
- compare to photos for test.
- it should be possible to swap out a cheaper strut however, the details are not straight forward. The main problem is that struts are usually pretty tall. The adjustable ones can be lowered, reducing their height by as much as 6" (more or less).
Wheels & Tires
- receive wheels with tires and lungnuts in mail (tirerack)
- jack up chassis; set up car jack; put wood block on car jack to avoid scratching frame.
- bolt on wheels; Lug wrench required
Braking Chassis
Pedal Plate
- receive pedal plate in mail or CNC on location.
- bolt pedal plate onto chassis; recieve grade 8, 3/8" bolts, washers, and lock nuts
- receive brake pedal in mail (willwood)
- receive brake master cylinder in mail (willwood)
- receive accelerator pedal in mail.
- bolt pedals and master cylinder to pre-drilled holes on pedal plate; recieve grade 8, 1/4" bolts, washers, and lock nuts
Brake Lines
- receive brake lines in the mail, pre-flared or flare on location; if flaring on location, requires bubble flare tool, metric AND SAE brake line fittings.
- bend lines to match diagram
- receive brake line clips in the mail
- attach clips to existing holes on pedal plate and chassis according to diagram
- screw on brake line fittings; line/flare wrench required, SAE and Metric
Brake Fluid
- buy, locally, DOT3 brake fluid; CAUTIION: Brake fluid is one of the few seriously toxic fluids we deal with. Be careful, goggles and latex gloves are suggested.
- fill brake fluid resevoir
- bleed brakes; Requires brake bleeder kit or modified empty water bottle or 3/16th surgical tube.
- Verify brake pressure; Step on brake and verify rock-hard pedal before pedal is fully depressed. Have friends heave on the car and verify car slides before wheels rotate.
Steering Chassis
Steering Rack
- receive steering rack in the mail.
- receive steering rack mounts in the mail or make locally with CNC.
- bolt steering rack mounts to pedal plate; recieve grade 8, 3/8" bolts, washers, and lock nuts
- bolt steering rack to steering rack mounts; recieve grade 8, 3/8" bolts, washers, and lock nuts
- receive tie rod extendors in the mail or tap locally from hexagonal bar stock.; if tapping locally, need metric tap, I believe M14x1.5.
- receive tie rods in the mail.
- thread tie rods onto tie rod extendors.
- thread tie rod extendors onto steering rack.
- bolt tie rods to steering knuckles.
- verify can heave on front wheel by hand and one wheel does not move at all without the opposite wheel moving.
Steering Column
- receive steering column in the mail.
- receive interior module in mail or cut and weld locally; same tools required as making a chassis.
- set interior module in chassis, and bolt in; recieve grade 8, 3/8" bolts, washers, and lock nuts
- receive steering wheel in the mail.
- slide steering column onto steering rack, tighten pinch bolt; metric socket set required.
- attach steering column to interior module.
- Bolt steering wheel to steering rack; SAE socket set required
- verify steering wheel turns both wheels without wobbling.
- align wheels (professional alignment or local with speed square, plumb bob, and level).
Body On
Body Top Mount Frame
- receive body top mount frame in the mail
- receive button-head hex bolts in mail.
- bolt body top mount frame to car
- receive body by freight.
- set body onto body top mount frame.
- bolt body on to body top mount frame with button-hread hex bolts.
- push and shake body, verify does not flex, wobble, or make noise under force that would dent a fender on a new car.
- dust and polish car body.
Build Steps for Volume Scenarios
Chassis Machining
- extrusions set on templates on aluminum router
- aluminum milling
- test milled aluminum on test fixture (welding jig)
Chassis Weld
- seam weld along marked paths in welding jig
Mold Making
- foam on foam router
- foam milling
- test foam on test fixture (CMM)
- send picture from CMM super-imposed over foam photo to customer
- visual inspection and scabbing in
Composites Layup
- unroll prepreg sheets onto body,
- place core material on router
- test core material on test fixtures
- place core material in mold.
- unroll prepreg sheets over core material
- place thermocouples and vacuum ports in mold
- place vacuum sheet in mold
- place pleats as needed in vacuum sheet.
- test vacuum seal, troubleshoot.
- apply vacuuum
Composites Debulking
- remove vacuum bag, tensile strength test flashing, take picture and send to customer
- remove from mold, grind off flashing. sand.
Body Finishing
- place on CNC
- CNC drills body access holes and mount holes
- sand body
- wash body
Vinyl Wrap
- print vinyl wrap
- unroll vinyl wrap
- apply, squeegee, heat, disperse bubbles of wrap.
Suspension Corners
- assemble dampers
- adjust dampers
- assemble knuckles
- assemble A-arms to suspension plates with Heim joints
- assemble strut top mounts to plates with bolts
- attach steering kunckles to damper bodies
- attach steering knuckles and dampers to suspension plates
- assemble calipers
- attach rotors and calipers
- place all 4 suspension corners on test fixture
Engine Module
- assemble engine on engine test fixture (engine cradle)
- attach transmission, longblock components
- attach air intake, exhaust header, fuel system
- test fuel system
- test air system
- test compression
- dyno and fuel consumption test on test jig,
Electrical Module
- form electrical module box (router, or vacuum form, or composite)
- load PCB on router
- machine PCB
- set PCB on test fixture
- place PCB in electrical module box.
- solder in wiring connections
- pot in wiring connections
- connect wiring connections to RJ45 jacks
- place RJ45 jacks in knockouts on electrical module box
- connect electrical module box to test fixture
Body Electrical
- insert lights and sensors into body
- attach Cat5e cable to body, connect to lights and sensors
- connect body electrical to test fixture
- see machining, mold, body electrical steps.
- Interior module
- dash panel
- pedal plate
- HVAC system
- stereo
- windsheild wiper and fluid
- door/hinge/clam/latches
- rolling chassis
- cargo spaces/liners/lighting
- wheel wells
- integrated vehicle test
- ABS
- VSC
- tire pressure monitoring
- MILs
- alignment check jig