Fergo ASC and VR3 Documentation Break Down
- Noah Hickman
DISCLAIMER: These are based on the Release C ASC 2024 Regulations and therefore may need to be revised for future iterations of the regulation documents.
Light Blue Highlighter = Comments and extra concerns, not actual regulation
All-Encompassing ASC Regulations
5.1.A - PVDR Contents
5.1.A.2 Roll over and impact protection for the driver
Within the PVDR, we will need to include design information and supporting data on our structural chassis and roll cage that protects the driver. This includes things relevant to safety like the roll cage, seat, helmet, seatbelt, etc.
5.2.B - Mechanical Technical Report
5.2.B.1 Design issues involved in impact, roll over and suspension scenarios
Chassis rollover is very important to us and Dynamics, in which we need to help optimize the center of gravity and create a chassis that is optimal in the case of a rollover.
5.2.B.2 Address vehicle stability, including center of gravity and relative weights on each wheel. Documentation with calculations and/or testing should be provided.
Again center of gravity and center of weight are important to us here.
9.5 Visibility
9.5.A Eye - Height In the normal driving position with a fully laden solar car, all occupant’s eyes must be at least 700 mm above the ground.
Not only does this have to do with occupant space design, but seat and dashboard designs as well.
10.3.A Occupant Cell
10.3.A.7 The Occupant Cell shall encompass the occupant in all directions. When occupants are seated normally, with safety-belts and helmets on, no part of any occupant, nor the full free range of motion of the occupant’s head (including helmet), may intersect with the convex hull of the Occupant Cell.
This basically means that the driver and their head cannot pass a certain point in the occupant cell, so as to injure them in the case of a crash/roll. This means that the roll cage needs to be built in conjunction with the driver model.
10.3.A.14 There must be 50 mm of clearance in all directions between any member of the Occupant Cell and the helmets of the occupants seated in the normal driving position. There must be at least 30 mm of clearance between the occupant’s helmet and the padding to allow for free movement of the occupant’s head.
Self-explanatory design concern.
10.3.C Occupant Space
10.3.C.1 The occupant space for each occupant’s upper torso shall be defined by an arc defined with an 835 mm radius measured from the hip point as defined in Appendix B of the occupant and projects forward 45 degrees from vertical, 25 degrees rearwards and 7 degrees side-to-side from the centerline of the occupant.
Frame+Ergo concern - make sure to check critical roll cage dimensions w/ a driver model inside to ensure adequate driver clearance.
10.3.C.2 The solar car structure, including the windshield must lie wholly outside the occupant space. The steering wheel, mirrors, seat backs, and head restraints may be inside the occupant space but must be designed to minimize the risk of injury to the occupant.
Frame+Ergo+Aeroshell concern - Being communicative between systems will be crucial for chassis design.
Appendix E. Mechanical PVDR Form
Appendix G. Mechanical VDR Form
Appendix F. Mechanical Report Instructions
F.3 Vehicle Impact Analysis
The vehicle impact analysis section must include the following topics:
F.3.1 Specifications: The report must describe the vehicle frame and construction techniques (aluminum space frame, composite monocoque, etc.), including the materials utilized, their important dimensions (e.g., tubing diameters and thicknesses, number and types of plies in composite constructions), and their properties (in the "as welded" or "as fabricated" condition). The report must also list the specific impact criteria that are assumed for each case, as well as sample calculations and computer output as applicable. Other relevant assumptions used in the analysis should be listed.
F.3.2 Drawings: The report must include structural drawings of the vehicle from five viewpoints: top, front, side, rear, and isometric. These drawings must illustrate the following: Driver location and orientation All members considered "structural" Locations of ballast and batteries Locations of chassis hard points (points of attachment). Calculated center of mass The report must contain structural drawings of the driver's compartment from three viewpoints: top, front, and side. These drawings must illustrate the following: Driver location Roll cage design and location Location of structural members Driver's harness attachment points The report must contain an isometric drawing of the body and solar collector, a. All drawings must be identified by number and must include a description.
Frame-Specific ASC Regulations and Design Concerns
8.4 Battery Enclosures
8.4.B Mounting - The battery enclosures must be secured to the solar car chassis so as to prevent them or the modules within from coming loose in the event of an accident or rollover.
This is here mainly to remind us that the battery box and connection to the frame/chassis are integral to our design process and one of our key design considerations. We must be able to securely and efficiently house the battery box while keeping it fixed during vehicle operation and easy to access during maintenance.
9.1 Solar Car Dimensions - The solar car (including solar collector) may not exceed the following maximum dimensions when moving under its own power: Length = 5.0 m Height = 1.6 m Width = 2.2 m
These are our rough building dimensions, but keep in mind the aeroshell as well. But overall, this gives us a rough idea of what our car should fit in, and therefore what the frame should fit in (even though we should try and make the frame as skinny and light as it can be .
9.5 Visibility
9.5.B Forward and Sideward Vision
9.5.B.4 Some elements of the roll cage may obstruct a portion of the forward vision. However, this view must be essentially unobstructed as much as is reasonably possible by the solar car structure.
Of course the goal is to NOT have any tubes within the view of the driver, but if need be, we can obstruct the vision of the driver slightly if structurally necessary.
10.3 Cockpit - The cockpit may not subject the solar car occupants to excessive strain during normal operation, and must be designed to protect the occupants from injury in the event of an accident. The occupants must be provided adequate space for safe operation of the vehicle. Care needs to be taken in the design and construction of the vehicle to minimize the risk that any shafts or sharp objects could penetrate the cockpit in the event of a crash and potentially injure the occupants.
10.3.A Occupant Cell
10.3.A.1 Roll Cage: is the structural cage that encompasses the occupants from the level of the top of the shoulders upward. Any structure above the shoulder is considered to be part of the roll cage.
This is the part that protects the driver from falling out the car/hitting the ground in the event of a roll.
10.3.A.2 Structural Chassis: is the tubular frame / monocoque composite chassis / hybrid of composite & tubular frame which encompasses the occupant’s bodies, and to which the vehicle suspension system is connected.
This is the rest of the chassis, hopefully made of aluminum honeycomb panelling and tubular structure.
10.3.A.3 All solar cars must be equipped with a roll cage that is fixed and integrally connected to the structural chassis.
In our case, this won’t be a problem, as it is welded directly to the rest of the frame structure. HOWEVER, in the event of a fully monocoque frame, we would need to bolt the roll cage to the composite structure.
10.3.A.4 The roll cage shall be constructed with metal elements. Composite roll cages are not permitted.
Though composite structures are rigid and can take lots of stress, they tend to yield more than metals and are not plastic (meaning they do not go back to their original orientation or shape after being exposed to load).
10.3.A.5 The combination of the solar car structural chassis and roll cage comprises the Occupant Cell.
Self explanatory.
10.3.A.6 Teams must provide documentation that specifies which parts of their solar car constitute the Occupant Cell.
This will be provided in PVDR and VDR.
10.3.A.8 Each team must provide calculations, certified by the team’s certifying reviewer, to show that the Roll Cage will not yield and all other components of the Occupant Cell will not deform by more than 25 mm and will not fail (exceed ultimate strength) at any point when subjected to the load cases outlined in Appendix F, section F.3.3, where g is the total gross mass of the vehicle including all occupants and ballast as submitted in the Mechanical PVDR Form (Appendix E).
We just need to supply the proper simulation documentation to validate our design.
10.3.A.9 The protection provided for the occupants in a collision must be documented in the team’s Mechanical Technical Report as per Reg. 5.2.B.
Self explanatory.
10.3.A.10 A preliminary sketch and description of the Occupant Cell must be submitted to ASC Headquarters by the date indicated in Reg. 4.3.A.1, as per Reg. 5.1.A.
Self explanatory.
10.3.A.11 In addition to providing collision and rollover protection, the roll cage must be designed so as to deflect body/array panels of the car up and away from the occupants in the event of an accident. The front roll cage shall be angled backwards to facilitate deflection of the body/array panel. When occupants are seated normally, with safety-belts and helmets on, the full free range of motion of the occupant’s head (including helmet) shall not be able to protrude from the front of the roll cage
Basically the front roll hoop needs to be angled in order to deflect debris. Also the driver should not go past the front roll hoop when using full free range of motion.
10.3.A.12 Wherever the Occupant Cell may come in contact with an occupant’s helmet, the roll cage or structure must be padded with energy-absorbing material meeting SFI-45.1 or FIA 8857-2001 Type A or B, or better. This material must be bonded and secured to the structure, wrapping around 50% of the roll cage member or piece of vehicle structure.
Frame must be padded with foam.
10.3.A.15 Any carbon fiber panels rigidly attached to the Occupant Cell within 500 mm of the center of an occupant’s head in a normal seated position and above the top of the occupant's shoulders shall have shatter-resistant fabric (such as Kevlar or Dyneema) applied to the interior surface of the panel. The layer or layers shall total at least 5 oz/yd2 of fabric weight. In this context, “rigidly attached” includes any panel that is part of the occupant cell structure, or bolted or bonded to the Occupant Cell. This does not include panels that are part of a removable top shell held on by an array attachment system as described in 10.1.C. This regulation in no way allows for composite roll cages. It addresses composites that are not part of the Occupant Cell structure, but near the occupant’s head or neck, as well as Occupant Cell panels below the shoulder, but near the driver’s head or neck. The protection layers should have the minimum feasible number of cuts or breaks needed to conform to surface curvature.
We need to follow these guidelines as we look into sandwich panel designs.
10.4 Fasteners
All fasteners must be of suitable type, strength, and durability for their application. Friction, glued, or press fit assemblies will not be accepted in critical areas as the sole means of retention. For glued or press fit assemblies, a pin is required. The pin diameter shall be ¼ of the tube’s outer diameter. A press fit roll pin is acceptable for this application. Set screws intended to transmit torque or force will not be accepted. Fasteners must meet the following minimum requirements:
10.4.A Bolts - Bolts used in critical areas must at minimum meet SAE grade 5, metric grade M8.8 and/or AN/MS specifications. Bolts must be of the correct length, and extend at least two threads beyond the nut. Bolts in tension must not have shaved or cut heads. All fasteners should be properly torqued. U-bolts are not allowed in critical areas.
10.4.B Securing of Fasteners - All structural and other critical fasteners (bolts, nuts) must have an acceptable form of securing such that the fastener cannot loosen or be removed unintentionally. Acceptable methods of securing are: (1) Bolts with flex-loc type nuts or other nuts that use flexure as the means of locking and are reuseable. (2) Bolts with pre-drilled shafts and castle nuts with cotter pins installed to prevent loosening (3) Bolts with pre-drilled heads and/or nuts properly safety wired with stainless steel wire from 0.024” (0.6 mm) to 0.032” (0.8 mm) diameter conforming to Mil Spec MS20995C. The safety wire between fasteners and anchor points must be twisted to prevent loosening rotation of the fastener. (4) In blind hole applications, bolts with pre-drilled heads properly safety wired. (5) Other methods of securing fasteners may be deemed acceptable at the discretion of the Inspector. Securing methods that are not acceptable are Nylon lock nuts, "lock" washers, Loctite, or lock nuts that use thread distortion as a means to secure the nut. Lock nuts with thread distortion are not considered to be reusable. Other methods of securing fasteners where the above methods are not appropriate may be considered at the discretion of the Inspector. Non-critical fasteners need not be secured with lock nuts.
10.4.D Buckles and Straps - Plastic luggage type buckles or single push release straps are not considered acceptable means of securing any Critical Area. If nylon type straps are used in securing any Critical Area, ratchet type straps (without hook terminators) shall be used.
10.8 Towing Hardpoint
Solar cars must be equipped with a hardpoint where an appropriate rope or strap may be attached in order to tow the car for emergency recovery purposes. The hardpoint must be either securely attached to or part of a nonmoving structural component such that the car can be towed in the forward direction. The hardpoint or access to the hardpoint may be covered while not in use. The hardpoint must allow the car to be pulled with the body installed on the car; however, the canopy may be removed.
F.3 Vehicle Impact Analysis
F.3.3 Analysis: Analyzes may be in the form of computer modeling (such as a finite-element analysis) or empirical testing of the actual vehicle or its components. For finite-element analysis of the roll cage, 3D elements shall be used for analysis of all joints. Either a full 3D element model of the roll cage shall be used, or a shell or beam model of the roll cage shall be used to set the boundary conditions for detailed 3D models of each joint that extend at least 2x the tube diameter from the toe of the weld. Shell or beam elements are acceptable for analysis of the remainder of the occupant cell. Shell elements shall be acceptable for finite-element analysis of the roll cage if the factor of safety is 1.4 or greater. In any case where a minimum factor of safety of less than 1.1 is reported via finite-element analysis, additional data shall be required to validate the finite element model.
F.3.3.1 Occupant Cell Impact: Front, rear, and side impact with another vehicle assumes a bumper height of 100 mm, a width of 600mm, and elevation off the ground of 350 mm as shown in Figure 5. The occupant cell shall not deform more than 25 mm and shall not exceed ultimate strength, but can yield (10.3.A.8). The required load cases are: 1. Front 2. Rear 3. 3 side impact locations. One of these locations shall be the worst case bending moment on the side of the occupant cell.
F.3.3.2 Roll Cage Impact: Roll cage impact scenarios shall have a loading patch no more than 150mm diameter. The roll cage can not exceed yield strength (10.3.A.8). The required load cases are: 1. Combined Loading (5g down, 4g backward, 1.5g lateral) 2. Sideways angled loading (5g at 30 degrees downward from horizontal) 3. Sideways angled loading (5g at 60 degrees downward from horizontal) 4. Sideways horizontal loading (5g at the top of the hoop) 5. Rearward horizontal loading (5g at the top of the hoop) Each load case should be evaluated when applied to the front and rear roll hoop (10 load cases total). An example of the combined roll cage loading case for the front hoop is included in Figure 6. Emphasis should be placed on how protection is provided for the driver under these conditions. All impact scenarios must take into account movement of body panels and the vehicle's solar collector to ensure that these members do not penetrate the space occupied by the driver during the impact.
Ergonomics-Specific ASC Regulations and Design Concerns
9.4 Lighting
9.4.I Horn - Solar cars shall be equipped with a horn that can be heard at a sound power level between 75 and 102 dBA at a distance of 15 m in front of the solar car. The horn shall be permanently mounted, operated from the steering wheel, and shall be able to operate for up to 5 minutes continuously at the required volume.
Serves as a reminder that a) we need a horn button integrated in our steering wheel and b) we need to find a mounting location with the aeroshell/frame to mount the horn.
9.5 Visibility
9.5.F Outside Air Circulation - Outside air, from intake vents directed toward the occupant’s face, must be provided. Should intake vents from the wheel openings be used, the natural air flow rate through the ducting to the occupant compartment shall be augmented by a ventilation fan.
This is more so an ergonomics concern due to mounting locations located in the occupant cell (aka is this mounting to the dashboard or would we possibly look at working with the frame system to integrate it with the roll cage?)
9.6 Egress
9.6.A Performance Requirement
9.6.A.1 Teams shall define primary and secondary directions for egress. The primary and secondary directions must be separated by at least 90 degrees and both primary and secondary directions cannot be on the same side of the solar car.
Not necessarily a huge huge design concern unless we make the car/OC asymmetrical, but just know that egress is tested in two directions.
9.6.A.2 For Single-Occupant solar cars, teams will be required to demonstrate that the occupant can exit the vehicle unassisted, standing clear of the plane of the car, in less than 10 seconds for the primary direction and less than 15 seconds for the secondary direction.
To put it lightly, we failed this regulation on our last car. Egress needs to be a point of emphasis in this design cycle, as the car needs to be easily accessible and safe for the occupant. All in all, we are shooting for a sub 10-sec egress on both sides.
9.7 Ballast
The official weight of each occupant, including clothes (including shoes, excluding helmet, with empty pockets), will be 80 kg. If an occupant weighs less than 80 kg, ballast will be added to make up the difference. If an occupant weighs more than 80 kg, no credit will be given. A ballast is a way of making up the extra weight needed to meet the 80 kg goal. 80 kg is chosen as it is a good weight target to maintain stability during vehicle operation (in terms of weight balance, center of mass/gravity, etc.)
9.7.A Ballast Bag - Each registered solar car occupant will be allowed one container to contain their required ballast. Containers will be a single colored canvas bank (coin) bag with dimensions of 305 mm x 482.5 mm. Ballast must be able to be contained within the canvas bag allowing security seals to be applied. Consideration should be made to ensure that a full ballast container will fit securely in the car’s ballast carrier(s).
Essentially we need to take each driver, assign them a bag, and then make up the difference between 80kg minus their mass, to meet the proper ballast requirements
9.7.B Ballast Box
9.7.B.1 Each solar car must have one (1) ballast box for each occupant.
This can be fabricated or procured, just ensure that a) in the event of catastrophic failure, the opening of the box is NOT TOWARDS the driver and that b) proper latching and fastening equipment is utilized, as well as in the proper orientation (some fasteners better in shear than in tension)
9.7.B.2 Each Ballast Box shall have a lid that is secured closed for carrying ballast. The Ballast Box(s) must be securely fastened to a structural member of the solar car and/or be demonstrated to hold the ballast fixed in the event of an impact. Each occupant’s Ballast Box shall be located within a 300 mm horizontal distance of the occupant’s hip location.
Keep in mind location of ballast box and also do not ziptie to the frame, utilize proper clamping and fastening techniques.
9.7.C Common Ballast
9.7.C.1 Teams entered in the Single-Occupant class may elect to use a Common Ballast.
9.7.C.2 Should a team elect to use a Common Ballast, then each solar car driver shall have one (1) individual ballast bag and the Common Ballast bag. The sum of the two (2) ballast bags shall be equal or greater than the ballast required to bring the driver’s weight up to 80 kg as per Reg. 11.2.
A common ballast is just a way to make the driver-specific ballasts smaller in mass, with one bag (the common ballast) making up most of the weight.
9.7.C.3 Teams that plan to use a Common Ballast must equip their cars with a Common Ballast Box that complies with 9.7.B.2. This box may be located anywhere within the vehicle. The Common Ballast bag will be sealed within the Common Ballast Box at the start of the event.
See Reg 9.7.B.2, same gist.
9.7.D Ballast Access - Occupants and their corresponding ballast will be identified with unique identification tags. The tags on the ballast carried by the solar car must match the tags on the occupant at all times. The ballast container and its identification and security markings must be visually accessible by the Observer during driver changes.
Ballast must be easily accessible, properly sealed, and labeled according to the driver it pairs with.
9.7.E Ballast Type - Teams will provide their own material for ballasting purposes. Ballast types allowed shall be either steel shot, lead shot, or coin. All other types of ballast will not be allowed. Consideration should be made with respect to the density of material selected and a driver’s weight to ensure that the required ballast needed will fit into the container provided.
Basically, just pick one of these materials that will fit into our ballast box when in bulk amounts.
10.1 Body Panels
10.1.A Covers and Shields All moving parts must be suitably covered to prevent accidental human contact when the solar car is fully assembled. The driver must be shielded from contact with all steering linkage and other moving parts.
Shield the OC area from the suspension, steering rack, anything mechanical, etc., etc.
10.3 Cockpit
10.3.A Occupant Cell
10.3.A.13 A head restraint of at least 19 mm thick resilient material must be securely mounted behind the occupant’s head without the use of cable ties, fabric straps, or temporary attachments. The headrest must support the occupant’s head in normal driving position.
Need a headrest that is comfy
10.3.B Occupant Seats
10.3.B.1 Single-Occupant solar cars shall be designed for 1 occupant with only one seat.
No having 9 seats like a minivan
10.3.B.3 Each solar car occupant must have a seat that faces forward at an angle less than 10 degrees from the forward direction of travel.
Self-explanatory design dimensions.
10.3.B.4 Each seat must have a back and a head restraint per Reg 10.3.A.13. The distance from the hip point to the top of the head restraint must be at least 800 mm for front seats and those of a single occupant solar car and at least 750 mm for rear seats. (49 CFR 571.202a - Standard No. 202a; Head restraints). The hip point may be approximated as shown in the diagram below. Any additional seat padding must be included in this measurement.
Self-explanatory design dimensions.
10.3.B.5 Each occupant’s heels must be below their hip point.
Self-explanatory design dimensions.
10.3.B.6 The angle between each occupant’s shoulders, hips and knees must be more than 90 degrees.
Self-explanatory design dimensions.
10.3.B.7 Any additional seat padding must be positively secured to the seat.
Self-explanatory.
10.3.C Occupant Space
10.3.C.3 The driver’s head must be above and behind the driver’s feet. The seat must be appropriately constructed with a solid base and backrest.
Again, incorporate the driver model early into the frame. Make an IRL ergo jig so we can test with/ drivers of varying heights/builds and maximize comfort…?
10.3.D Belly Pan - The cockpit must be equipped with a full belly pan to isolate the occupants from the road. The belly pan must be strong enough to support the full weight of each occupant. Each occupant’s torso and limbs must be above the lower element of the structural chassis.
Self-explanatory design dimensions.
10.3.E Safety Belts
10.3.E.1 All solar cars must be equipped with a minimum of a 5-point lap and shoulder belt harness system for each occupant.
10.3.E.2 The use of safety belts is mandatory.
10.3.E.3 The safety belts must be installed and attached securely to the structural chassis, as recommended by the manufacturer. Safety belt mounts should be designed to resist the same impact loads that the safety cell is designed for (Reg 10.3.A.8)
10.3.E.4 If the belt passes through the seat, it must pass through without wrinkling, crimping or bending the belt excessively. All sharp edges shall be removed or covered to prevent cutting or fraying of the belt.
10.3.E.5 Only safety belt systems manufactured and certified to FIA 8853/98, FIA 8853-2016, SFI 16.1, SFI 16.5, or SFI 16.6 are allowed. Any modifications must be approved by the manufacturer.
10.3.E.6 The placement of the attachment points for the seat belt harness shall be as follows (unless otherwise specified by the manufacturer):
10.3.E.7 The shoulder straps attachment point shall be rearwards between horizontal and highest of 30 degrees below horizontal and perpendicular to the occupant’s spine or seat back Figure 10.2 Range of shoulder strap attachment position
10.3.E.8 The shoulder belts shall be spaced wide enough apart to not squeeze on the neck, but narrowly enough that they will not fall off the shoulders. The mounting points shall extend backward and go inward by approximately one unit for every two units that the mounting point is located behind the point that the belt leaves the shoulder
10.3.E.9 The lap belt attachment point shall be downwards and rearwards from the occupant’s lap between 60 degrees and 80 degrees from horizontal. The ends of the belt need to be well below the lap of the driver.
10.3.E.10 The anti-submarine belt attachment shall be approximately 10 degrees forward of plane of shoulder belts for 5-point or approximately 20 degrees rearward of plane of shoulder belts for 6-point belts.
10.4 Fasteners
10.4.E Critical Areas For application of the above critical areas are defined to include: steering, braking, suspension, seat mounts, safety harness, drive train, battery box, ballast carrier, and parking brake. 10.4.E.1 Brake caliper systems present unique challenges to securing of fasteners. Teams should contact the inspectors prior to the event with any unique securing situations. Caliper securing will be evaluated in terms of total system redundancy.
10.5 Brakes
10.5.A Configuration - Solar cars must have a dual, balanced braking system so that if one system should fail, the solar car can still be stopped. The two systems must be operationally independent and must operate from a single foot pedal. The braking system can be front/rear or redundant front. Left/right redundancy is not permitted. Hydraulic systems must have separate master cylinders. Regenerative brakes may not be considered as one of the braking systems.
10.5.B Brake Pads - Each brake pad used in the braking systems must have a contact area with the brake disk that is greater than 6.0 cm2 , and the pad must have full contact with the brake rotor. Pads must initially be at least 6 mm thick including the backing plate when installed on the car.
10.5.C Braking Performance - Solar cars must be able to repeatedly stop from speeds of 50 km/h (31 mph) or greater, with an average deceleration, on level wetted pavement, exceeding 4.72 m/s2 . Performance shall be demonstrated with mechanical braking only.
10.5.D Brake Lines/Cables - The brake lines (hydraulic or cable) shall be appropriately sized and constructed such that they have significant capacity beyond the pressure and/or loads that will occur under the worst-case driving conditions.
10.5.E Clearance between Pedals - If the team elects to have foot operated brake and accelerator pedals the team must demonstrate adequate clearance and arrangement that will allow for quick and easy transition of the foot from one pedal to the other. Refer to Reg. 8.8.B for placement of the accelerator pedal if equipped. 10.5.F Hand Activated Brakes Hand activated brakes are permissible if the driver can turn the steering wheel lock-to-lock without removing or repositioning either hand from the steering wheel. 10.5.G Cars with Mechanical Rear Brake 10.5.G.1 For solar cars without anti-lock brakes, the front wheels must lock-up before the rear wheels. 10.5.G.2 Performance: Cars with mechanical rear brakes as one of their primary brake systems shall be able to demonstrate that the rear brake can hold the car in place (front wheels elevated off the ground) on dry pavement under a forward pull equal to 15% of the cars weight in Tour configuration with properly ballasted driver in place. 10.5.G.3 Volume Limiting Valve-System: cars with mechanical rear brakes with proportioning valves will require a means to lock-out the proportioning valve setting. The proportioning valve shall be positioned out of any occupant’s reach.
10.6 Parking Brake
Solar cars must be equipped with a parking brake.
10.6.A Performance - The parking brake shall be able to hold the car in place without wheel chocks on dry pavement under either a forward or rearward force equal to 10% of the cars weight in fully loaded condition.
10.6.B Independence - This brake must operate completely independently from the main braking system and may not be used in the performance tests specified in Reg.10.9.D.
10.6.C Locking
10.6.C.1 It must be able to be locked into the “ON” position, such that the driver does not have to continue to hold it to maintain position.
10.6.C.2 The driver shall be able to set and lock the parking brake while seated in the normal driving position and seat belted in.
10.6.C.3 The driver shall be able to set and lock the parking brake in a single action or motion.
10.6.D Contact Style - The parking brake shall not be of a tire or wheel contact style (i.e. pad on tire or pad on rim styles are not considered as acceptable designs).
10.7 Steering
10.7.A Steering Wheel - All steering in the vehicle must be controlled by the driver with a steering wheel designed to have a continuous perimeter as outlined in Appendix A. The steering wheel must be sufficiently strong to withstand loads the driver may impose on it. Steering wheels 3D printed on hobby-grade FDM printers are extremely unlikely to pass inspection
11.2 Helmets
All solar car occupants must wear a helmet while operating the solar car. The helmet must meet or exceed the Snell M2010, Snell M2015 or Snell M2020, DOT FMVSS, ECE 22.05, AS/NZS 1698, or equivalent international motorcycle standards and will be inspected during Scrutineering.
11.5 Water/Fluids
Each occupant must have sufficient quantities of water/fluids in the cockpit area to stay properly hydrated. A minimum of two liters for each occupant must be provided.
11.6 Driver Communication
11.6.A Driver Communications - All communications by the solar car driver must be verbal and hands-free at all times. Hands-free operation is defined as operation where the driver can activate the radio without removing their hands from the steering wheel. If voice communication systems utilize volume detection rather than a push-to-talk button to initiate transmission, the communication system must be full-duplex.
11.6.B Cell Phone Use
11.6.B.1 Cell phones are permitted within the solar car. Any use of a cell phone by the solar car driver will need to be on a hands-free basis. Use of cell phone must comply with all local laws pertaining to cell phone use within a vehicle. Any cell phone must be fixed in position (i.e. not loose within the driver compartment).
11.6.B.2 See 12.5.B for cell phone use on ASC, 14.4 for cell phone use on FSGP
11.6.C Solar Vehicle Driver Communication For both Single and Multi-Occupant vehicles, the driver of the solar car must be in communication with the solar car caravan.
Appendix A. Steering Wheel Specifications
To reduce the possibilities of driver injury in the event of collision and to minimize impediments to emergency egress, the steering system must be controlled by a steering wheel which has a continuous perimeter. A circular shape is preferred, however the upper part above 2/3 and/or the lower part below 2/3 of the circumference of the steering wheel may be flat as depicted in the diagram below).
Appendix B. Occupant Space Diagram
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