StockEVO
10-02-2006, 09:36 AM
AEM is producing a more advance ACD controller for EVO with the active diff. Pretty much a EMS for your ACD.
"The ACD is a replacement controller for the Lancer Evo 7/8/9 active diff system. It uses all the same sensors and valves as the original system but uses a completely new strategy. The ACD is a hydraullically controlled system using a small electric pump the product reservoir pressure and a proportional control valve to adjust the controlling pressure. The control pressure is controlled by the wheel speeds, handbrake, footbrake and throttle postition. In addition there are 5 modes of operation: Off, Gravel, Snow Tarmac and Lock."
Control Strategy
OFF Cal
There are 5 CAL modes ( refered to as the Cal )of operation 3 active modes OFF and
LOCK mode.
On power up the CAL mode is set by the Default Mode option.
The values of the Default Mode option are: 0 off
10 Gravel
20 Snow
30 Tarmac
40 Lock
Each mode is selected in turn by pressing and releasing the CAL button. OFF Cal is
indicated by all three of the Cal LEDS on the dash board are off. In OFF Cal the
accumulator pump is switched off.
LOCK Cal
LOCK Cal is indicated by all three mode LEDs being on. In LOCK the demanded
pressure is set by the LockPRS option. The hand brake can be set to release the lock
pressure if the Hbrk in lock option is set to ON, in which case the demand pressure
will be set by the Handbrake press option when the handbrake is operated.
Active Cals
The 3 Active Cals Tarmac Gravel Snow are selected in turn by pressing and releasing
the CAL button. The relevent LED is illuminate to idicate which mode is selected.
In the active modes the strategy is the same in each mode but the active regime
calibrations can be different .
There 5 regimes, START, HANDBRAKE, FOOTBRAKE, ACCEL and DECCEL.
The current regime is determined by the various system inputs.
START
Regime = 36
The Start regime is selected if the average wheel speed is 0 KPH for 5 seconds.
The Start regime is exited when average wheel speed is >STARTspd option
In the Start regime the control pressure is set by the Start Prs table . This table has
TPSVAL as an input and CNT_DEM pressure as an output. There are 11 sites
covering the TPSVAL range of 0-100 % in 10% steps. The control pressure can be set
from 0 to 25 bar.
The Handbrake can interrupt the Start regime if the Hbrk in Start option is on
The Start regime is disabled if STARTspd option =0
HAND BRAKE
Regime = 12
The Handbrake regime is selected if the hand brake switch is activated by pulling the
hand brake leaver. In the Hand brake regime Demand is set by the Handbrake press
option .
FOOT BRAKE
Regime = 20
The Foot Brake regime is selected if the Brake lights are On ,the Throtle < TPS left
foot brake option.(Throttle position for left foot braking) and the Hand brake is not
operated. In Foot brake regime is set by the FBRKprs option. This can be set from 0
to 25 bar.
DECCEL
Regime =24
The Deccel regime is selected if none of the above regimes are selected and the
Throttle < CDCLTPS option. In the Deccel regime the pressure is set by one of 3 3D
look up tables ( SnowD GravelD and TarmacD ) which table is used is set by the
mode. The mode is set by pressing the Mode switch on the dash board.
The Deccel look up table has input axis for Slip and Average Wheel Speed (KPH).
Slip is the difference between Average front wheel RPM and Average rear wheel
RPM (Fastest – Slowest ).
The Average wheel speed axis has 8 sites and each site can be to a KPH value of 0 to
255 KPH. (Site 0 must be the slowest and site 7 the fastest). The Slip axis has 5 sites
and starts at 0 with steps set by the RPMSTEP option.
Each site in the table can be set to a Demand value of 0 – 25 bar.
ACCEL
Regime = 28
The Accel regime is selected if none of the above regimes are selected and the
TPSVAL > CACLTPS option. In the Accel regime the pressure is set by one of 3 3D
look up tables ( SnowA GravelA and TarmacA ) which table is used is set by the
mode. The mode is set by pressing the Mode switch on the dash board.
The Accel look up table has input axis for Slip and Average Wheel Speed (KPH).
Slip is the difference between Average front wheel RPM and Average rear wheel
RPM (Fastest – Slowest ).
The Average wheel speed axis has 8 sites and each site can be to a KPH value of 0 to
255 KPH. (Site 0 must be the slowest and site 7 the fastest). The Slip axis has 5 sites
and starts at 0 with steps set by the RPMSTEP option.
Each site in the table can be set to a CNT_DEM value of 0 – 25 bar.
Settings
There are 6 3D look up tables, 3 2D look Up tables, 11 Calibration options and 7
Control options. Which are all user programmable and must be set for the Control
Strategy to work correctly.
The Calibration options set the non control related features of the system
Here are some more info http://www.roadraceengineering.com/evo/EVO7ACD-20for-20V1.011.pdf
"The ACD is a replacement controller for the Lancer Evo 7/8/9 active diff system. It uses all the same sensors and valves as the original system but uses a completely new strategy. The ACD is a hydraullically controlled system using a small electric pump the product reservoir pressure and a proportional control valve to adjust the controlling pressure. The control pressure is controlled by the wheel speeds, handbrake, footbrake and throttle postition. In addition there are 5 modes of operation: Off, Gravel, Snow Tarmac and Lock."
Control Strategy
OFF Cal
There are 5 CAL modes ( refered to as the Cal )of operation 3 active modes OFF and
LOCK mode.
On power up the CAL mode is set by the Default Mode option.
The values of the Default Mode option are: 0 off
10 Gravel
20 Snow
30 Tarmac
40 Lock
Each mode is selected in turn by pressing and releasing the CAL button. OFF Cal is
indicated by all three of the Cal LEDS on the dash board are off. In OFF Cal the
accumulator pump is switched off.
LOCK Cal
LOCK Cal is indicated by all three mode LEDs being on. In LOCK the demanded
pressure is set by the LockPRS option. The hand brake can be set to release the lock
pressure if the Hbrk in lock option is set to ON, in which case the demand pressure
will be set by the Handbrake press option when the handbrake is operated.
Active Cals
The 3 Active Cals Tarmac Gravel Snow are selected in turn by pressing and releasing
the CAL button. The relevent LED is illuminate to idicate which mode is selected.
In the active modes the strategy is the same in each mode but the active regime
calibrations can be different .
There 5 regimes, START, HANDBRAKE, FOOTBRAKE, ACCEL and DECCEL.
The current regime is determined by the various system inputs.
START
Regime = 36
The Start regime is selected if the average wheel speed is 0 KPH for 5 seconds.
The Start regime is exited when average wheel speed is >STARTspd option
In the Start regime the control pressure is set by the Start Prs table . This table has
TPSVAL as an input and CNT_DEM pressure as an output. There are 11 sites
covering the TPSVAL range of 0-100 % in 10% steps. The control pressure can be set
from 0 to 25 bar.
The Handbrake can interrupt the Start regime if the Hbrk in Start option is on
The Start regime is disabled if STARTspd option =0
HAND BRAKE
Regime = 12
The Handbrake regime is selected if the hand brake switch is activated by pulling the
hand brake leaver. In the Hand brake regime Demand is set by the Handbrake press
option .
FOOT BRAKE
Regime = 20
The Foot Brake regime is selected if the Brake lights are On ,the Throtle < TPS left
foot brake option.(Throttle position for left foot braking) and the Hand brake is not
operated. In Foot brake regime is set by the FBRKprs option. This can be set from 0
to 25 bar.
DECCEL
Regime =24
The Deccel regime is selected if none of the above regimes are selected and the
Throttle < CDCLTPS option. In the Deccel regime the pressure is set by one of 3 3D
look up tables ( SnowD GravelD and TarmacD ) which table is used is set by the
mode. The mode is set by pressing the Mode switch on the dash board.
The Deccel look up table has input axis for Slip and Average Wheel Speed (KPH).
Slip is the difference between Average front wheel RPM and Average rear wheel
RPM (Fastest – Slowest ).
The Average wheel speed axis has 8 sites and each site can be to a KPH value of 0 to
255 KPH. (Site 0 must be the slowest and site 7 the fastest). The Slip axis has 5 sites
and starts at 0 with steps set by the RPMSTEP option.
Each site in the table can be set to a Demand value of 0 – 25 bar.
ACCEL
Regime = 28
The Accel regime is selected if none of the above regimes are selected and the
TPSVAL > CACLTPS option. In the Accel regime the pressure is set by one of 3 3D
look up tables ( SnowA GravelA and TarmacA ) which table is used is set by the
mode. The mode is set by pressing the Mode switch on the dash board.
The Accel look up table has input axis for Slip and Average Wheel Speed (KPH).
Slip is the difference between Average front wheel RPM and Average rear wheel
RPM (Fastest – Slowest ).
The Average wheel speed axis has 8 sites and each site can be to a KPH value of 0 to
255 KPH. (Site 0 must be the slowest and site 7 the fastest). The Slip axis has 5 sites
and starts at 0 with steps set by the RPMSTEP option.
Each site in the table can be set to a CNT_DEM value of 0 – 25 bar.
Settings
There are 6 3D look up tables, 3 2D look Up tables, 11 Calibration options and 7
Control options. Which are all user programmable and must be set for the Control
Strategy to work correctly.
The Calibration options set the non control related features of the system
Here are some more info http://www.roadraceengineering.com/evo/EVO7ACD-20for-20V1.011.pdf