frc::SlewRateLimiter< Unit > Class Template Reference

A class that limits the rate of change of an input value. More...

#include <frc/filter/SlewRateLimiter.h>

Public Types
using	Unit_t = units::unit_t<Unit>
using	Rate = units::compound_unit<Unit, units::inverse<units::seconds>>
using	Rate_t = units::unit_t<Rate>

Public Member Functions
	SlewRateLimiter (Rate_t positiveRateLimit, Rate_t negativeRateLimit, Unit_t initialValue=Unit_t{0})
	Creates a new SlewRateLimiter with the given positive and negative rate limits and initial value.
	SlewRateLimiter (Rate_t rateLimit)
	Creates a new SlewRateLimiter with the given positive rate limit and negative rate limit of -rateLimit.
Unit_t	Calculate (Unit_t input)
	Filters the input to limit its slew rate.
Unit_t	LastValue () const
	Returns the value last calculated by the SlewRateLimiter.
void	Reset (Unit_t value)
	Resets the slew rate limiter to the specified value; ignores the rate limit when doing so.

Detailed Description

template<class Unit>
class frc::SlewRateLimiter< Unit >

A class that limits the rate of change of an input value.

Useful for implementing voltage, setpoint, and/or output ramps. A slew-rate limit is most appropriate when the quantity being controlled is a velocity or a voltage; when controlling a position, consider using a TrapezoidProfile instead.

See also

TrapezoidProfile

Member Typedef Documentation

Rate

template<class Unit >

using frc::SlewRateLimiter< Unit >::Rate = units::compound_unit<Unit, units::inverse<units::seconds>>

Rate_t

template<class Unit >

using frc::SlewRateLimiter< Unit >::Rate_t = units::unit_t<Rate>

Unit_t

template<class Unit >

using frc::SlewRateLimiter< Unit >::Unit_t = units::unit_t<Unit>

Constructor & Destructor Documentation

SlewRateLimiter() [1/2]

template<class Unit >

frc::SlewRateLimiter< Unit >::SlewRateLimiter ( Rate_t positiveRateLimit, Rate_t negativeRateLimit, Unit_t initialValue = Unit_t{0} )

inline

Creates a new SlewRateLimiter with the given positive and negative rate limits and initial value.

Parameters

positiveRateLimit	The rate-of-change limit in the positive direction, in units per second. This is expected to be positive.
negativeRateLimit	The rate-of-change limit in the negative direction, in units per second. This is expected to be negative.
initialValue	The initial value of the input.

SlewRateLimiter() [2/2]

template<class Unit >

frc::SlewRateLimiter< Unit >::SlewRateLimiter ( Rate_t rateLimit )

inlineexplicit

Creates a new SlewRateLimiter with the given positive rate limit and negative rate limit of -rateLimit.

Parameters

rateLimit

The rate-of-change limit.

Member Function Documentation

Calculate()

template<class Unit >

Unit_t frc::SlewRateLimiter< Unit >::Calculate ( Unit_t input )

inline

Filters the input to limit its slew rate.

Parameters

input

The input value whose slew rate is to be limited.

Returns

The filtered value, which will not change faster than the slew rate.

LastValue()

template<class Unit >

Unit_t frc::SlewRateLimiter< Unit >::LastValue ( ) const

inline

Returns the value last calculated by the SlewRateLimiter.

Returns

The last value.

Reset()

template<class Unit >

void frc::SlewRateLimiter< Unit >::Reset ( Unit_t value )

inline

Resets the slew rate limiter to the specified value; ignores the rate limit when doing so.

Parameters

value

The value to reset to.

---

The documentation for this class was generated from the following file:

• frc/filter/SlewRateLimiter.h