Rules Question Summary For Website.

2015

1/2015

• We've noticed that CAMS now requires many forms of motorsport to use frontal head restraint (HANS) devices, and we'd like to clarify whether or not that will be a requirement for Formula SAE as well, as it would represent a fairly large expenditure to procure the restraints, new seat belts etc

• CAMS show same as prior years that Frontal Head restraint is “B” for Speed Events which is recommended but not required.  FSAE 2015 Rules are as in previous years and do not require it, nor recommend it.

• It has not been proposed at all for Formula even in future years.   I think our event speeds and circumstances minimise any need.

• We also require arm restraints of course which are not mentioned at all in the CAMS requirements.

• I think our position should/would thus be that our required equipment standards stay as in prior years and we do not require (or recommend) such devices.

Question Answer

3/2015T3.40.3• Each attachment point requires a

minimum of two (2) 8 mm Metric Grade 8.8 (5/16 inch SAE Grade 5) bolts

• Does this rule only refer to attaching primary structures to the monocoque (e.g. the rear sub frame) or does it include wishbone pickups and suspension mounting points?

• The rules T3.40.3 specifically relates to the attachment of other parts of the Primary Structure to a monocoque shell.   Other attachment points are not required to conform to this mounting design but should be designed to meet the anticipated loads and strength of the monocoque and installed using sound engineering practice.

Question Answer

4/2015

T7.1.9• Brake Pedal must be fabricated

from steel or aluminium or machined from steel, aluminium or titanium

 • Specifically, we are asking as to

whether the brake pedal can be 3D printed by titanium (Arcam titanium 6-4) and then post-machined. In the Electron Beam Melting (EBM) process, dense metal components are built up, layer-by-layer of metal powder and melted by a powerful electron beam. Each layer is melted to the exact geometry defined by a CAD model.

• The rules specifically only allow pedals fabricated from Aluminium or Steel, with Titanium accepted only if machined from solid stock.  Your deposited design is thus not acceptable.  

Question Answer

5/2015

T9.2.2• When viewed from the front of the

vehicle, the part of the front wheels/tires that are more than 250 mm (9.8 inches) above ground level must be unobstructed by any part of the aerodynamic device, with the exception of any vertical surfaces (end plates) less than 25 mm in thickness.

 • What is acceptable as an endplate

in the region of the tyre from the top to a plane running 250mm from the top surface?  Please see pictures below

• The intent of the rule is to not allow a greater than 25 mm lateral width of vision obscuration in front of the tyre.  Your first design would appear to significantly exceed this whereas the second design is in line with the intent of the rule for a simple flat endplate running parallel to the vehicle centreline, provided the maximum thickness at any point does not block more than 25 mm width of the tyre.

Question Answer

7/2015

T10.2• "The driver and anyone standing

outside the car must be shielded from any hydraulic pumps and lines"

 • If the body of the chassis (carbon

skins with nomex core) separates the line and driver, would this still require an additional 1mm metal shield?

• Provided that the lines are fully shielded (i.e no openings that may allow impact) from both the driver and any external bystander by the structural material you describe, a separate shield per T10.2 Is not required.

Question Answer

9/2015EV 3.3.3• Maintenance plugs, additional contactors or similar measures

have to be taken to allow electrical separation of the internal cell segments such that the separated cell segments contain a maximum static voltage of less than 120VDC and a maximum energy of 6MJ. The separation must affect both poles of the segment.

EV 3.4.11• The accumulator segments contained within the accumulator

must be separated by an electrically insulating and be fire resistant barrier (according to UL94-V0, FAR25 or equivalent) and must subdivide the accumulator into 6MJ segments if this is not already met by the separation due to the 120VDC voltage limit.

• NOTE: The contained energy of a stack is calculated by multiplying the maximum stack voltage with the nominal capacity of the used cell(s). Documentation of segment separation must be provided in the ESF.

• We are uncertain as to how the energy stack is calculated; can you please provide the formula used for this calculation?

• This segmentation into 6MJ will require repackaging of our 2014 battery package, as we believe we exceed this maximum allowable energy limit. Our batteries were purchased and packaged last year before these rules were released, and we intended to utilise these batteries for two years given the significant cost of batteries. In order to comply to this rule change, we would have to disassemble the current battery packs and repackage them but we are concerned about the strength of the cell tabs due to heat cycling. Repackaging the battery cells to meet this rule amendment could be more dangerous than to leave the battery packaging in its current state, which we believe to be around 7MJ.

• The calculation of Energy Stack per EV3.4.11 is derived from • maximum static voltage per module = # of cells x Max

Voltage per cell.   • maximum energy per module = # of cells x Rated Capacity

x Max Voltage per cell x 3600 J/Wh.        • From your 2014 data the limit of 6.8MJ would be exceeded. • We are, however, for 2015 only, willing to allow the use of the

nominal voltage for the energy calculation only.  • (Maximum Voltage must still be used in the Maximum Voltage

per module calculation).• The separation of the subsequent segments to meet the 6MJ

limit must be created by use of maintenance plugs • or similar contacts which can be disconnected without the

use of tools.

Question Answer

10/2015IC4.6• It was not the intention of the rules committee to

introduce more restrictive voltage limits within the IC category which prevents the use of OEM 12V charging systems. If the charging system is OEM and designed for a DC battery voltage less than 60V then the 25VAC limit of rule IC4.6 does not apply, however the system must either use the stock wiring between the generator and the rectifier, or this wiring must be rated to at least the maximum output voltage of the rectifier. If student teams are electing to build a charging system then rules must be followed.

• We would like to replace the stock regulator/rectifier with an aftermarket unit. To be clear, the replacement unit will not be constructed by students. For the benefit of the committee, this is the link to the product we are considering:

• http://www.ebay.com.au/itm/Compu-Fire-55402-Regulator-for-40A-3-Phase-Charging-Systems-60-3337-/331114765797

• In our case the wiring would remain stock with the connector being replaced with an appropriately rated plug. In this way we believe the replacement would comply with the intention of the rules (safe charging system) especially as it is not uncommon for teams to substitute OEM regulators with units from similar bikes.

• The approach you propose is acceptable provided that appropriately rated connector/plug is used and the OE, or appropriately rated, wiring is used.

Question Answer

11/2015IC3.2.1 • The sound level will be measured during a

static test. Measurements will be made with a free-field microphone placed free from obstructions at the exhaust outlet level, 0.5 m (19.68 inches) from the end of the exhaust outlet, at an angle of forty-five degrees (45°) with the outlet in the horizontal plane. The test will be run with the gearbox in neutral at the engine speed defined below. Where more than one exhaust outlet is present, the test will be repeated for each exhaust and the highest reading will be used.

•  In the case of dual exhaust outlets, does the committee intend for four test locations in total?

• We would argue that considering each outlet in isolation and testing accordingly may result in the microphone becoming too proximate to the other outlet. In an exhaust arrangement as described, would only the two outboard test locations be considered?

• To focus on only the outboard location would not meet the wording of the rules and in fact the inner location may be louder (by chance, or by design) than the outer.  Accordingly you should assume that the Scrutineers will measure at 4 locations for dual exhaust systems. The maximum measurement of these will be the one recorded, irrespective of potential interference from other outlets.

Question Answer

12/2015

• Can we attach the seatbelt attaching eye bolts by welding? • No. Refer T5.2.2 for minimum

mounting bracket requirements

Question Answer

14/2015

• Rule T.3.25.3.c says that 'The diagonal side impact structural member must connect the upper and lower Side impact structural members forward of the main hoop and rearward of the front hoop‘

• Rule T3.25.4 says that 'With proper

triangulation, it is permissible to fabricate the side impact structural members from more than one piece of tubing'

• The use of a triangulated diagonal side impact tube made up of additional tubes meeting at a supported node (as indicated in your diagram with the 4 additional tubes meeting at the mid-point node) complies with Rule T3.5.5, and the nominated two-piece supported diagonal complies with the diameter and thickness requirements of T3.4.1, the diagonal tube in the plane of the upper and lower tubes may be removed.

Question Answer

15/2015• Our team are after a rules clarification on the front roll

hoop, in particular T3.12.2.• • "T3.12.2 The Front Hoop must extend from the lowest

Frame Member on one side of the Frame, up, over and down to the lowest Frame Member on the other side of the Frame."

• • For a carbon fibre monocoque chassis does this mean

the front roll hoop must the lowest panel (the floor panel) of the chassis and sit flush with the bottom of the monocoque, or does this mean that the roll hoop must butt up against the lowest panel of the monocoque?

• • I interpret it as that it must butt up against the lowest

panel, however I am not sure and would like clarification.

• • We are also after a clarification on the rules for

Monocoque front bulkheads:

• The key aspect is that the hoop must extend down to the lowest structurally equivalent part of the monocoque. Whether this terminates by effectively “butting up” to the floor panel or is partially integrated into or through to the exterior lower surface of the floor panel, is up to the team in their final design but, provided all of the related monocoque requirements for retention of the hoop are met, either approach is acceptable.

• FSAE-A Rules Committee.”

Question Answer

16/2015• T3.32 Monocoque Front Bulkhead See Rule T3.28 for general

requirements that apply to all aspects of the monocoque. In addition when modeled as an “L” shaped section the EI of the front bulkhead about both vertical and lateral axis must be equivalent to that of the tubes specified for the front bulkhead under T3.19. The length of the section perpendicular to the bulkhead may be a maximum of 25.4mm (1”) measured from the rearmost face of the bulkhead. 46 © 2014 SAE International. All Rights Reserved 2015 Formula SAE® Rules – 09/17/2014 Revision. Furthermore any front bulkhead which supports the IA plate must have a perimeter shear strength equivalent to a 1.5 mm thick steel plate.

• • We are unsure as to what constitutes a "front bulkhead

supporting the IA plate".• -Does the "IA Plate" refer to the anti intrusion plate?• -Does "Supporting the IA Plate" mean bolting the anti

intrusion plate to the bulkhead• -Because the Anti Intrusion Plate extends to the outer edges

of the bulkhead, is it not being supported by the front bulkhead and front roll hoop supports as well?

• • We are a bit confused about this rule as it requires around 5-

6mm thick facesheets of carbon fibre to pass the perimeter shear requirement, and I know that in the past other teams have had nowhere near that, so it would be good to get some clarification.

• The basic rules help clarify in addition to the specific monocoque requirements. As per

• T3.21.2 On all cars, a 1.5 mm (0.060 in) solid steel or 4.0 mm (0.157 in) solid aluminium “anti-intrusion plate” must be integrated into the Impact Attenuator. If the Impact Attenuator and Anti-Intrusion Plate (Impact Attenuator Assembly) are bolted to the Front Bulkhead, it must be the same size as the outside dimensions of the Front Bulkhead. If it is welded to the Front Bulkhead, it must extend at least to the centreline of the Front Bulkhead tubing in all directions.

• it clarifies that the IA plate and Anti-Intrusion plate are the same item.

• • Reference in T3.32 to a bulkhead supporting the IA plate applies

for all cases where the bulkhead is of monocoque construction rather than tubular metal.

• If the IA plate does not extend to the outer periphery of the bulkhead then a support meeting this requirement must be provided across the front bulkhead plane. If your IA extends, and is bolted, to the outer periphery of the bulkhead, then in addition to verifying that the EI of your composite bulkhead (whether of L section or other shape) it must also meet the perimeter shear strength equivalency to a 1.5 mm steel section.

• This added requirement versus a tubular metal bulkead is to protect for the potential brittle failure of a monocoque structure and is based on overseas experience.

• • FSAE-A Rules Committee”

Question Answer

17/2015• T3.32 Monocoque Front Bulkhead • See Rule T3.28 for general requirements that apply to all aspects of

the monocoque. In addition when modeled as an "L" shaped section the EI of the front bulkhead about both vertical and lateral axis must be equivalent to that of the tubes specified for the front bulkhead under T3.19. The length of the section perpendicular to the bulkhead may be a maximum of 25.4mm (1") measured from the rearmost face of the bulkhead.

• Furthermore any front bulkhead which supports the IA plate must have a perimeter shear strength equivalent to a 1.5 mm thick steel plate.

• Is the perimeter shear strength for this rule calculated from the first peak as for shear strength, or the second peak in the load/displacement graph as for perimeter shear strength in T3.33.3/T3.34.3?

• In response to your query, for equivalence to a 1.5 mm thick steel plate, the perimeter shear strength for this rule should be calculated from the second peak in the load/displacement graph as for perimeter shear strength in T3.33.3/T3.34.3.

• Yours Sincerely• FSAE-A Rules Committee”

Question Answer

21/2015

• Modification of the metal part as you propose is acceptable as it should not create added weight or load input to the fuel rail. You must ensure that the OE design and parts making the connection to the plastic parts are maintained as originally supplied.

Question Answer• “IC1.9 (Page 86) Fuel Injection System Requirements Add; Fuel

Rails: In line with Formula Student, the fuel rail must not be made from any form of flammable material, plastic, carbon fibre or rapid prototyping material, except that unmodified OE Fuel Rails manufactured from these materials and supplied with the engine are acceptable.”

• • We currently use the Honda CBR600RR (07-09) engine and I

have attached an image of its OE fuel rail to this email for reference. As you can see it is made from three parts, two of which are plastic (previously disallowed material) and the centre part being made of a metal (previously allowed material regardless of modification). I would like to clarify if modifying the metal part of the fuel rail would conflict with this rule, even if the plastic parts were to remain unchanged?

• • We would like to modify the centre piece/machine our own

which would allow us to only have one port to the rail, as we run a return-less system which differs to the stock fuel system which requires a supply and return port on the rail. This modification would also allow us to use a different, more suitable fitting.

• • If you could advise as to whether or not this action would

conflict with the above mentioned rule that would be greatly appreciated.

22/2015

• An electrically driven supercharger is acceptable but it must receive its primary input energy from the alternator/generator driven by the IC engine and use the same battery that is used to start the vehicle and is recharged by the alternator/generator. A separate battery to power the supercharger would not be acceptable, as it would contravene the rules by providing another source of unmeasured stored energy.

• FSAE-A Rules Committee”

Question Answer

• I have a question about rule IC1.1.1 from article 1 titled "Engine limitation“

• It reads "Hybrid powertrains, such as those using electric motors running off stored energy, are prohibited." We would like to run an electric supercharger with our internal combustion engine. Is the intent of this rule just to prohibit you from running an electric motor that directly powers the wheels?

• Can we still use the stored energy off a battery to spin an electric supercharger to achieve a flatter torque curve given that this electric motor will have NO direct connection to the drive line?

23/2015The rule in question is T3.34.2 and reads as follows: 1. T3.34.2 The vertical side impact zone between the upper surface of the floor and 350 mm (13.8 inches) above the ground must have a Buckling Modulus (E*I) equivalent to two baseline steel tubes and the horizontal floor must have a Buckling Modulus (E*I) equivalent to one baseline steel tube per Rule T3.30 Monocoque Buckling Modulus. This rule clearly states that the floor is to be equivalent to "one baseline steel tube." As we began design of our monocoque towards the end of last year, we read and understood this rule in its meaning and have applied it to our 2015 vehicle. Our chassis has been designed for two months and we are a month into the manufacture of our chassis. This week, we were alerted to a clause within the SES Guidance Notes for Side Impact that reads as follows: "The horizontal floor (up to the centre of the chassis), when calculated as a flat panel must have equivalent EI to one baseline side-impact tube" We feel that the fact that this clause states that the horizontal floor should be measured "(up to the centre of the chassis)" is a complete contradiction to rule T3.34.2. This is since, in effect, this clause means that the floor must be equivalent to two baseline side-impact tubes across its total width and hence is in conflict with the above rule T3.34.2. We are also surprised that such an important rule has been included in a "Guidance Notes" tab in the SES rather than the rules document itself. The main purpose of these Guidance notes is to assist teams in their interpretation of the SES structure rather than to impose restrictions of such magnitude so to change the way that a rule itself is read in such a huge fashion. If this clause were contained within the rules document itself, we would have no problems with it, however since this is not the case we feel that it is a very unfair thing to impose upon teams. The fact remains that we are here, having followed the rules contained within the FSAE Rules Document to the meaning of each word contained within it and now are having to consider making drastic design changes to our monocoque in order to pass a clause that is not referenced to at all within the rules that we are meant to follow. So, I am writing to you to clarify as to where do we stand with this rule and if we can continue with our current design on account of a vague clause within a part of the SES that is not referred to anywhere else in any document and since we are so far into our build process already. At the very least we would like to make this known to the Rules Committee so that it can be amended for 2016 such that more teams do not get tricked by this in the future.

• For monocoque vehicles, the approach is to consider ½ vehicle width in any of the relevant requirements. Although the wording in the rules changed, the SES requirement is unchanged from 2014 which had to be met by prior monocoque teams. Accordingly, you need to design to comply with the detail method of the SES.

• • We agree that the wording in the rules

could be clearer and have raised this matter with the International Rules Committee.

• • FSAE-A Rules Committee.”

26/2015• I am seeking clarification on the following

rule;

• T3.9 - "All equivalency calculations must prove equivalency relative to steel grade SAE/AISI 1010."

• • By specifically stating SAE1010 are we

required to source that specific grade or is the intent of the rule in line with T3.4.1 - "Either: Round, mild or alloy, steel tubing (minimum 0.1% carbon) of the minimum dimensions specified in the following table" ?

• • Directly, can the baseline tube tested be a

steel grade with equal to or greater carbon content to SAE1010 or does it have to be specifically SAE1010?