Tommy Cookers wrote: ↑25 Aug 2022, 16:16
my (first 2) suggestions above - can someone explain what would stop them working ?
Stu mentioned the accelerator pedal and injector regs. I've looked, but I'm not seeing them as limiting the ICE to MGU interaction. Perhaps he can help point out the specifics?
5.14 & 5.15 (2026) define the relationship between the pedal map and the +ve torque to the rear wheels. However, they are framed in terms of net PU output. So, for the accelerator pedal at 0%, it's possible to run the ICE at +350kW and the MGU at -350kW for a net zero PU output.
The benefit is as you say, the turbine is already producing boost when the driver goes on the throttle, so all that problem with lag goes away.... plus you're harvesting energy for the later acceleration phase. All, in all, it seems very attractive to aim for running the ICE at full power for 100% of the lap, and modulating PU output using the MGU (at least in qualifying).
Braking is a point of contention, and there's a design choice of when to bring the ICE "on power". It's perfectly possible to do it early in the braking phase when the revs have dropped sufficiently for the output from ICE to balance the harvest from the MGU.
2026 regs
5.14 Power unit torque demand
5.14.1 The only means by which the driver may control acceleration torque to the driven wheels is
via a single foot (accelerator) pedal mounted inside the survival cell.
5.14.2 Designs which allow specific points along the accelerator pedal travel range to be identified by the driver or assist him to hold a position are not permitted.
5.14.3 At any given engine speed the driver torque demand map must be monotonically increasing for an increase in accelerator pedal position.
5.14.4 At any given accelerator pedal position and above 4,000rpm, the driver torque demand map must not have a gradient of less than – (minus) 0.045Nm/rpm.
5.14.5 The driver maximum torque demand may only be reduced at a maximum rate of 100kW in any 1s period and the power reduction will be limited to a maximum of 450kW.
5.15 Power unit control
5.15.1 The maximum delay allowed, computed from the respective signals as recorded by the FIA ADR or FIA Standard ECU, between the accelerator pedal position input signal and the corresponding output demands being achieved is 50ms.
5.15.2 Teams may be required to demonstrate the accuracy of the power unit configurations used by the FIA Standard ECU.
5.15.3 Power unit control must not be influenced by clutch position, movement or operation.
5.15.4 The idle speed control target may not exceed 4,000rpm.
5.15.5 A number of power unit protections are available in the FIA Standard ECU.
A minimum of nine seconds hold time should be configured for the power unit protections enabled during qualifying and race. The configuration of the air tray fire detection and throttle failsafe are exceptionally unrestricted in order to allow each team to achieve the best level of safety.
5.15.6 The power unit must achieve the torque demanded by the FIA standard software.
5.15.7 In order to measure the torque generated by the power unit the following sensors must be
fitted:
a. Each driveshaft must be fitted with a torque sensor which has been manufactured and calibrated by an FIA designated supplier to a specification determined by the FIA.
b. The power unit output shaft must be fitted with a torque sensor which has been manufactured and calibrated by an FIA designated supplier to a specification determined by the FIA.
c. The MGU-K must be fitted with a torque sensor which has been manufactured and calibrated by a FIA designated supplier to a specification determined by the FIA. The installation of the MGU-K torque sensor must be approved by the FIA.
The installation and the connectivity of each of these torque sensors to the FIA Standard ECU must be approved by the FIA.
5.15.8 Engine plenum air temperature must be more than ten degrees centigrade above ambient temperature. When assessing compliance, the temperature of the air will be the lap average recorded, by an FIA approved and sealed sensor located in an FIA approved location situated in the engine plenum, during every lap of the qualifying practice session and the race. The first lap of the race, laps carried out whilst the safety car is deployed, laps with a time at least 20% greater than the fastest lap of the session, pit in and out laps and any laps that are obvious anomalies (as judged by the FIA) will not be used to assess the average temperature. The ambient temperature will be that recorded by the FIA appointed weather service provider. This information will also be displayed on the timing monitors.
5.15.9 Any pressure sensor used to measure pressure of any fluid necessary to ensure the power unit functions correctly at all times (including but not limited to coolant, oil, fuel and air) must be manufactured by the single supplier appointed by the FIA World Motor Sport Council to a specification determined by the FIA Technical Department.
5.15.10 With the exception of exhaust temperature sensors and temperature sensors embedded in electronic boxes, any temperature sensor used to measure temperature of any fluid necessary to ensure the power unit functions correctly at all times (including but not limited to coolant, oil, fuel and air) must be manufactured by the single supplier appointed by the FIA World Motor Sport Council to a specification determined by the FIA Technical Department.
5.15.11 A maximum of one knock sensor per cylinder is permitted. This sensor must be an accelerometer-type and must be approved by the FIA Technical Department. The approval is also conditional upon such sensor being available on a non-exclusive basis and under normal and equivalent commercial terms to all Competitors. The approval request form must be sent by the sensor supplier to the FIA before the 1st of November of the preceding year.
5.15.12 No sensors of any kind capable of measuring or inferring internal cylinder pressure will be permitted.
