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No current limit ramp on swerve drive motorsΒ #209

@markpete

Description

@markpete

No current limit ramp on swerve drive motors 🟠 HIGH
File: src/main/java/frc/robot/generated/CompTunerConstants.java
Lines: 69–78

private static final TalonFXConfiguration driveInitialConfigs =
    new TalonFXConfiguration()
        .withCurrentLimits(
            new CurrentLimitsConfigs()
                .withSupplyCurrentLimit(Amps.of(80))
                .withSupplyCurrentLimitEnable(true)
                .withSupplyCurrentLowerLimit(Amps.of(40))
                .withSupplyCurrentLowerTime(Seconds.of(2))   // ← 2 s is too long
                .withStatorCurrentLimit(Amps.of(kSlipCurrent.magnitude()))  // = 120 A
                .withStatorCurrentLimitEnable(true));

Root cause: kSlipCurrent = 120 A stator per drive motor Γ— 4 modules = up to 480 A aggregate stator draw during aggressive acceleration or when wheels are spinning against an immovable object (e.g., cliff). The SupplyCurrentLowerTime = 2 seconds means sustained high supply current is allowed for 2 full seconds before throttling. In a 2.5-second auto sequence that's the entire auto.

The steer motors also have a 60 A stator limit (line 87) with no supply limiting at all.

Suggested fix:

// Drive motors
.withSupplyCurrentLimit(Amps.of(60))
.withSupplyCurrentLimitEnable(true)
.withSupplyCurrentLowerLimit(Amps.of(40))
.withSupplyCurrentLowerTime(Seconds.of(0.5))  // shorter ramp window
.withStatorCurrentLimit(Amps.of(80))          // reduce from 120
.withStatorCurrentLimitEnable(true)
// Steer motors β€” add supply limit
.withSupplyCurrentLimit(Amps.of(20))
.withSupplyCurrentLimitEnable(true)
.withStatorCurrentLimit(Amps.of(40))          // reduce from 60
.withStatorCurrentLimitEnable(true)

⚠️ Reducing kSlipCurrent (used as stator slip guard) to 80 A will reduce maximum traction available. Test on carpet to confirm adequate acceleration before competition.

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