4.6. Drivetrain Driver Request Controller - DrvrReq

• Overview

• Functions

• Ports

• Parameters

• Configuration Guide

Id	DrvrReq
Version	0.5.2.0
Title	Drivetrain Driver Request Controller
System	Drivetrain
Document Type	Application Software Component Specification Preview

4.6.1. Overview

The Driver Request component processes driver inputs such as accelerator pedal position, brake pedal position, and gear selection to determine the requested vehicle acceleration or deceleration. It performs parameter checks, signal conditioning, and interpolation of calibration tables to calculate the relative acceleration request. The component also handles creep mode functionality when the vehicle is at low speeds.

4.6.2. Functions

	Title	Description
1	Accelerator Pedal Signal Processing	Performs rate limiting and saturation on the accelerator pedal position input signal.
2	Brake Pedal Signal Processing	Performs rate limiting on the brake pedal position input signal.
3	Gear Selection Processing	Determines the current gear selection (Park, Neutral, Drive, Reverse) based on the gear position input.
4	Acceleration Request Calculation	Calculates the relative acceleration request by interpolating the accelerator pedal position and vehicle speed on calibration tables. The interpolation is performed based on the selected pedal map.
5	Brake Request Calculation	Calculates the relative brake request by interpolating the brake pedal position and vehicle speed on calibration tables when the brake pedal is pressed.
6	Creep Mode	Enables creep mode functionality when the vehicle speed is below a calibrated threshold and the accelerator pedal is not pressed. In creep mode, a small amount of torque is applied to slowly move the vehicle.
7	Parameter Checks	Performs various parameter checks on the calibration tables and configuration parameters to ensure data integrity and valid operating ranges. Faults are set if any checks fail.
8	Fault Handling	Monitors the component for any runtime faults and triggers the appropriate fault response, such as limiting the acceleration request or disabling certain features.

4.6.3. Ports

	Id	Direction	Data Type	Dimensions	Unit	Description	Keywords
1	Ts	Incoming	single	[1]	s		Ts
2	AccrPedlPosn	Incoming	single	[1]	%	Expected signal: Accelerator pedal position If signal is NA: mandatory.	Accelerator Pedal Position
3	BrkPedlPosn	Incoming	single	[1]	%	Expected signal: Brake pedal signal If signal is NA: mandatory.	Brake Pedal Position
4	BrkPedlIsPsd	Incoming	boolean	[1]	inherit	Expected signal: Brake is pressed flag. Example: flag active if a minimum threshold is reached If signal is NA: mandatory. False	Brake Pedal Is Pressed
5	ManBrkIsPsd	Incoming	boolean	[1]	inherit	Expected signal: Hand Brake Is Pressed flag. If signal is NA: mandatory. False	Manual Brake Is Pressed
6	VehLgtSpdPrcsdAbsv	Incoming	single	[1]	km/h	Expected signal: Absolute vehicle speed. If signal is NA: mandatory.	Vehicle Longitudinal Speed Processed Absolute
7	GearPosnAct	Incoming	Enum: CmnenaGearSt	[1]	inherit	Expected signal: Gear position feedback from Gear Selector If signal is NA: mandatory. CmnenaGearSt	Gear Position Actual
8	IgEngd	Incoming	boolean	[1]	inherit	Expected signal: Is vehicle with ignition engaged? If signal is NA: mandatory.	Ignition Engaged
9	CreepModReq	Incoming	boolean	[1]	inherit	Expected signal: Creep mode request If signal is NA: mandatory.	Creep Mode Request
10	PedlMap	Incoming	uint8	[1]	inherit	Expected signal: Inverter control system signal validity If signal is NA: mandatory. True	Pedal Map
11	DrvreqCreepModEngd	Outgoing	boolean	[1]	inherit		Drvreq Creep Mode Engaged
12	DrvreqVehLgtAReq	Outgoing	single	[1]	m/s/s		Drvreq Vehicle Longitudinal Acceleration Request
13	DrvreqDrvrTqLogInfo	Outgoing	uint8	[5]	inherit		Drvreq Driver Torque Log Information
14	DrvreqDiagc	Outgoing	Bus: DrvreqDiagc	[-1]	inherit		Drvreq Diagnostic

4.6.4. Parameters

	Id	Data Type	Dimensions	Range	Unit	Description	Keywords
1	DrvreqVehAMaxAvl	single	[1,1]	Min: 0, Max: 3.4e+38	m/s/s	Absolute Available Vehicle Long. Acceleration	Drvreq Vehicle Acceleration Maximum Available
2	DrvreqVehDeceMaxAvl	single	[1,1]	Min: 0, Max: 3.4e+38	m/s/s	Absolute Available Vehicle Long. Deceleration	Drvreq Vehicle Deceleration Maximum Available
3	DrvreqAccrMapRevSeld	uint8	[1,1]	Min: 1, Max: 5		Accelerator pedal map choice for backward vehicle move	Drvreq Accelerator Map Revolution Selected
4	DrvreqRgnCgryDiFlg	boolean	[1,1]	Min: 0, Max: 1		Disable CAT B Regenerative Torque when Brake Pedal Pressed	Drvreq Regeneration Category Disable Flag
5	DrvreqSwcCfgChg67Flg	boolean	[1,1]	Min: 0, Max: 1		Enable Traction/Regen Torque Availability logic based on CreepMode status	Drvreq Swc Configuration Change67 Flag
6	DrvreqAccrPedlPosnRateThd	uint16	[1,1]	Min: 0, Max: 65535	%/s	Rate limit of acc pedal position	Drvreq Accelerator Pedal Position Rate Threshold
7	DrvreqBrkPedlPosnRateThd	uint16	[1,1]	Min: 0, Max: 65535	%/s	Rate limit of brk pedal position	Drvreq Brake Pedal Position Rate Threshold
8	DrvreqCreepModARelMax	uint8	[1,1]	Min: 0, Max: 10	%	Creep mode acceleration percentage	Drvreq Creep Mode Acceleration Relative Maximum
9	DrvreqCreepModSpdThd	uint8	[1,1]	Min: 0, Max: 7	km/h	Creep mode torque speed limit	Drvreq Creep Mode Speed Threshold
10	DrvreqCreepModTqRiseTmr	single	[1,1]	Min: 0, Max: 10	sec	Set time to destinate creep accel max value	Drvreq Creep Mode Torque Rise Timer
11	DrvreqDynCfgFltLtchRstTmr	single	[1,1]	Min: 0.01, Max: 200	sec	Time period for reset fault dynamic setting signals switching check	Drvreq Dynamic Configuration Fault Latch Reset Timer
12	DrvreqDynCfgSwtCt	uint8	[1,1]	Min: 1, Max: 200		Maximum number of switching for dynamic setting signals	Drvreq Dynamic Configuration Switch Count
13	DrvreqDynCfgSwtTmr	single	[1,1]	Min: 0.01, Max: 200	sec	Time period for dynamic setting signals switching check	Drvreq Dynamic Configuration Switch Timer
14	DrvreqVehSpdRateThd	single	[1,1]	Min: 0.01, Max: 100	km/h/s	Vehicle Speed Rate Threshold for input processing	Drvreq Vehicle Speed Rate Threshold
15	DrvreqTwoPedlDrvVehSpdThd	single	[1,1]	Min: 0, Max: 15	km/h	Speed below which the brake and accelerator pedals can be simultaneously pressed without the accelerator request being overridden	Drvreq Two Pedal Drive Vehicle Speed Threshold
16	DrvreqTwoPedlDrvVehSpdHys	single	[1,1]	Min: 0, Max: 10	km/h	Difference between speed threshold when brake and accelerator pedals can be simultaneously pressed and speed when brake pedal has the highest priority	Drvreq Two Pedal Drive Vehicle Speed Hysteresis
17	DrvreqAReqAttnTblDa	single	[1,16]	Min: 0, Max: 100	%	Relative attenuation of positive relative acceleration demand by pressing as a function of brake pedal position	Drvreq Acceleration Request Attenuator Table Data
18	DrvreqAReqTblVehSpdPnt	single	[1,16]	Min: 0, Max: 3.4e+38	km/h	Speed reference points	Drvreq Acceleration Request Table Vehicle Speed Point
19	DrvreqAReqAttnTblBrkPedlPnt	single	[1,16]	Min: 0, Max: 100	%	Brake pedal position reference points	Drvreq Acceleration Request Attenuator Table Brake Pedal Point
20	DrvreqAReqTblDa2	single	[16,16]	Min: -1, Max: 1		Matrix 2 of relative accelearation request	Drvreq Acceleration Request Table Data2
21	DrvreqAReqRvsTblDa1	single	[16,16]	Min: -1, Max: 1		Matrix 1 of relative accelearation request	Drvreq Acceleration Request Reverse Table Data1
22	DrvreqAReqTblDa3	single	[16,16]	Min: -1, Max: 1		Matrix 3 of relative accelearation request	Drvreq Acceleration Request Table Data3
23	DrvreqAReqTblDa4	single	[16,16]	Min: -1, Max: 1		Matrix 4 of relative accelearation request	Drvreq Acceleration Request Table Data4
24	DrvreqRgnReqTblDa1	single	[16,16]	Min: -1, Max: 1		Map 1 Relative Braking Torque Request	Drvreq Regeneration Request Table Data1
25	DrvreqRgnReqTblDa2	single	[16,16]	Min: -1, Max: 1		Map 2 Relative Braking Torque Request	Drvreq Regeneration Request Table Data2
26	DrvreqRgnReqTblDa3	single	[16,16]	Min: -1, Max: 1		Map 3 Relative Braking Torque Request	Drvreq Regeneration Request Table Data3
27	DrvreqRgnReqTblDa4	single	[16,16]	Min: -1, Max: 1		Map 4 Relative Braking Torque Request	Drvreq Regeneration Request Table Data4
28	DrvreqAReqTblDa1	single	[16,16]	Min: -1, Max: 1		Matrix 1 of relative accelearation request	Drvreq Acceleration Request Table Data1
29	DrvreqAReqTblAccrPedlPnt	single	[1,16]	Min: 0, Max: 100	%	Accelerator pedal reference points	Drvreq Acceleration Request Table Accelerator Pedal Point
30	DrvreqRgnReqTblBrkPedlPnt	single	[1,16]	Min: 0, Max: 100	%	Brake pedal reference points	Drvreq Regeneration Request Table Brake Pedal Point

4.6.5. Configuration Guide

The DrvrReq component is calibrated to ensure proper driver input processing, acceleration request calculation, regenerative brake request calculation, and driveability requirements.

4.6.5.1. Step 1 - Calibrate Acceleration Pedal Map

The acceleration request is calculated based on the accelerator pedal position and vehicle speed. To ensure accurate acceleration response, the following parameters must be configured:

• Define the Accelerator Pedal Position Breakpoints The parameter DrvreqAReqTblAccrPedlPnt specifies the key pedal positions where acceleration request values are mapped.

• Set the Vehicle Speed Breakpoints The parameter DrvreqAReqTblVehSpdPnt determines the speed breakpoints used in acceleration calculations.

• Calibrate the Acceleration Request Table The parameters DrvreqAReqTblDa1 – DrvreqAReqTblDa4 define the acceleration request at each combination of pedal position and vehicle speed.

• Configure Reverse Mode Acceleration If acceleration characteristics need to be adjusted in reverse, the parameter DrvreqAReqRvsTblDa1 should be set to modify the request profile accordingly.

• Define Maximum Acceleration and Deceleration The parameters DrvreqVehAMaxAvl and DrvreqVehDeceMaxAvl define the upper ranges for acceleration and deceleration requests. These constraints prevent excessive acceleration or braking forces.

4.6.5.2. Step 2 - Calibrate Brake Pedal Map

Depending on the vehicle system architecture, the regenerative brake request might be computed on VCU side based on brake pedal position and vehicle speed. To achieve the desired deceleration response, configure the following parameters:

• Enable or Disable Regenerative Braking When Brake Pedal Is Pressed The parameter DrvreqRgnCgryDiFlg enables or disables regenerative braking when brake pedal is pressed. true means regen is disabled.

• Define the Brake Pedal Position Breakpoints The parameter DrvreqRgnReqTblBrkPedlPnt sets the key pedal positions where brake requests are mapped. These breakpoints allow interpolation of braking force based on pedal input.

• Set the Vehicle Speed Breakpoints for Braking The parameter DrvreqAReqTblVehSpdPnt specifies speed-based variations in braking request calculations. Proper tuning ensures braking behavior adapts to different speeds.

• Calibrate the Brake Request Table The parameters DrvreqRgnReqTblDa1 – DrvreqRgnReqTblDa4 define braking request values at different pedal positions and speeds. Adjust these values to optimize braking feel and response.

4.6.5.3. Step 3 - Calibrate Creep Mode

Creep mode enables the vehicle to move slowly forward at low speeds when the brake pedal is released and the accelerator is not pressed. This feature improves maneuverability in stop-and-go traffic and parking situations.

• Define Maximum Creep Torque The parameter DrvreqCreepModARelMax specifies the highest allowable torque applied in creep mode. Adjust this value to control the vehicle’s creeping behavior.

• Set the Speed Threshold for Creep Mode Activation The parameter DrvreqCreepModSpdThd determines the maximum speed at which creep mode remains active. Above this threshold, creep torque is disabled.

• Configure Two-Pedal Driving Detection

  The parameter DrvreqTwoPedlDrvVehSpdThd sets the vehicle speed limit above which pressing both pedals simultaneously may trigger specific actions.

  The parameter DrvreqTwoPedlDrvVehSpdHys defines the hysteresis for two-pedal detection to prevent unwanted switching between creep mode and normal operation.

• Adjust Brake Pedal-Based Creep Attenuation

  The parameter DrvreqAReqAttnTblBrkPedlPnt specifies brake pedal positions that influence creep torque reduction.

  The parameter DrvreqAReqAttnTblDa defines how torque is reduced as the brake pedal is applied.

4.6.5.4. Step 4 - Configure Input Processing and Fault Handling

The DrvrReq component monitors for faults and takes appropriate action to ensure safety. If an issue is detected, acceleration and braking may be adjusted accordingly.

• Rate-limit Accelerator, Brake Pedal and VehSpeed Signals

  The parameters DrvreqAccPedPosnRateThd, DrvreqBrkPedPosnRateThd and DrvreqVehSpdRateThd limit input signal change rates.

• Configure Intermittent Fault Detection

  The parameters DrvreqDynCfgSwtTmr and DrvreqDynCfgSwtCt define time window and counter threshold for signal-unstable fault detection.

  The parameter DrvreqDynCfgFltLchRstTmr sets the reset delay for faults that are latched dynamically.