Ford native curvature

[elkoled]

Moves Ford to the generic apply_std_curvature_limits, which works in lateral acceleration and lateral jerk space, same as the Tesla angle VM safety.
We apply it directly to curvature so no vehicle model is needed (lat_accel = curvature * v^2).

The three hand picked curvature rate breakpoints are replaced by two physical constants,
MAX_LATERAL_ACCEL = 3.6 m/s^2 and MAX_LATERAL_JERK = 3.6 m/s^3.

• Ford bronco test drive
• Ford bronco lateral reports

[github-actions]

Car behavior report

Replays driving segments through this PR and compares the behavior to master.
Please review any changes carefully to ensure they are expected.

Testing 91 segments for: FORD_BRONCO_SPORT_MK1, FORD_ESCAPE_MK4, FORD_ESCAPE_MK4_5, FORD_EXPLORER_MK6, FORD_F_150_MK14, FORD_F_150_LIGHTNING_MK1, FORD_FOCUS_MK4, FORD_MAVERICK_MK1, FORD_MUSTANG_MACH_E_MK1, FORD_RANGER_MK2

✅ 0 changed, 91 passed, 0 errors

[elkoled]

Removed rate limits as currently applied in VW MEB, kept ford max_curvature_error tracking in python and safety.

[elkoled]

New curvature limits:

New rate limit:

[sshane]

What is that in accel/jerk space?

[elkoled]

Same as Tesla VM:
unified 3.6m/s² lat accel and 3.6m/s³ jerk

accel:

jerk:

[adeebshihadeh]

We should really have these plots generated in the loop somewhere in the repo, rather than one-off scripts.

[elkoled]

Test drive
Lateral reports show same behavior before/after.
Also same behavior at highway speeds.
The EPS limits the commanded curvature.

Lateral Reports
master
curvature-safety

curvature-safety report has stepping around 9m/s which is FORDs no-blending threshold in carcontroller that is surfaced with the new permissive limits:

      # No blending at low speed due to lack of torque wind-up and inaccurate current curvature
      if CS.out.vEgoRaw > 9:
        apply_curvature = float(np.clip(apply_curvature, current_curvature - CarControllerParams.CURVATURE_ERROR,
                                        current_curvature + CarControllerParams.CURVATURE_ERROR))
      apply_curvature = apply_std_curvature_limits(apply_curvature, self.apply_curvature_last, CS.out.vEgoRaw,
                                                   0., CarControllerParams.STEER_STEP, CC.latActive,
                                                   CarControllerParams.CURVATURE_LIMITS)