tonic
Totally Hooked
- Aug 31, 2023
- 215
- 685
While digging through the 2023 GRY CAN bus, I found some electric power steering (EPS) signals that give a look at how the EPS ECU is assisting the driver.
If averaged out, the speed-dependent assist roughly looks like this:
(how much the system multiplies the driver's steering input at different speeds)
Standstill: 13.0 Nm assist per 1 Nm driver input
5–10 km/h: 8.4 Nm
10–30 km/h: 3.7 Nm
30–50 km/h: 1.9 Nm
50–70 km/h: 1.7 Nm
70–110 km/h: 1.3 Nm
The assist ratio isn't perfectly linear. It stays fairly flat during light steering inputs (depending on speed) and ramps up as the driver turns the wheel harder.
This map shows a more precise relationship between speed, driver torque, and assist, but takes more effort to read
I don't see any practical use for this, just found it interesting to put numbers to the feel.
If averaged out, the speed-dependent assist roughly looks like this:
(how much the system multiplies the driver's steering input at different speeds)
Standstill: 13.0 Nm assist per 1 Nm driver input
5–10 km/h: 8.4 Nm
10–30 km/h: 3.7 Nm
30–50 km/h: 1.9 Nm
50–70 km/h: 1.7 Nm
70–110 km/h: 1.3 Nm
The assist ratio isn't perfectly linear. It stays fairly flat during light steering inputs (depending on speed) and ramps up as the driver turns the wheel harder.
This map shows a more precise relationship between speed, driver torque, and assist, but takes more effort to read
I don't see any practical use for this, just found it interesting to put numbers to the feel.
