The wpimath APIs use std::array, which doesn't do size checking. Passing
an array with the wrong size can result in uninitialized elements
instead of a compilation error.
This is a breaking change but is worthwhile to avoid hard-to-debug errors.
The stall torque, stall current, and free current are now multiplied by
the number of motors instead of just the stall torque. This produces the
same values for Kt and Kv regardless of the number of motors; the motor
resistance still affects the system response.
For an elevator model, the response should be the same as before since a
factor of "number of motors" shows up in the same place in the
acceleration calculation, but the current calculation will also be
correct now.
frc::NormalizeAngle(), units::math::NormalizeAngle(), and
frc::GetModulusError() were replaced with frc::InputModulus() and
frc::AngleModulus().
They were placed in wpimath/src/main/native/include/frc/MathUtil.h for
C++ and wpimath/src/main/java/edu/wpi/first/wpiutil/math/MathUtil.java
for Java.
* Add .clang-tidy configuration.
* A separate .clang-tidy is used for hal includes to suppress modernize-use-using
(as these are C headers).
* Add NOLINT where necessary for a clean run.
* Add clang-tidy job to lint-format workflow. This workflow is now only run on PRs.
To reduce runtime, clang-tidy is only run on files changed in the PR.
Two wpilibc changes; both are unlikely to break user code:
* BuiltInAccelerometer: Make SetRange() final
* Counter: Make SetMaxPeriod() final
After these cleanups, the only file that does not run cleanly is
cscore_raw_cv.h due to it not being standalone.
This makes code easier to read and more consistent between C++ and Java.
Also update clang-format settings to always add a line break (even if no braces are used).
This adds an overload of UnscentedKalmanFilter::Correct() that takes a
custom measurement covariance but uses default mean and residual
calculation functions.
Closes#2965.
Pose and state estimators can filter latency-compensated global measurements and fuse them with state-space drivetrain model information to estimate robot position. They are drop-in replacements for the existing odometry classes.
Co-authored-by: Declan Freeman-Gleason <declanfreemangleason@gmail.com>
Co-authored-by: Prateek Machiraju <prateek.machiraju@gmail.com>
Co-authored-by: Claudius Tewari <cttewari@gmail.com>
Co-authored-by: Matt <matthew.morley.ca@gmail.com>
There were three options for where to put this function:
1. A free function in LinearQuadraticRegulator.h. Returning a K matrix
means the user can't use the LinearQuadraticRegulator in a loop
anymore.
2. A default argument added to ctors in LinearQuadraticRegulator for a
time delay (default of 0). This has the smallest API footprint from
the user perspective, but it bloats the already substantial
constructor overload set of LinearQuadraticRegulator.
3. A member function in LinearQuadraticRegulator that modifies the
internal K. This would still have to take in a LinearSystem or (A, B)
pair because the ctor doesn't store it. Storing it internally feels
like paying for what we don't use most of the time.
I went with option 3.
I verified the tests's expected values in Python with
scipy.linalg.fractional_matrix_power().
Closes#2877.
This address some problems with the LinearSystemLoop class that were discovered through testing.
The initial state estimate of the observer was set to the provided initial state rather than zero as previously, a non zero initial state passed into reset() would lead to a discrepancy between the current state estimate and the actual system state.
By storing the previous dt, it can be moved into Correct() where it is
actually used. This lets us take the continuous R as an argument in the
user-provided R overload.
This does not introduce any breaking changes for teams that used the TrajectoryGenerator API for
quintic splines with poses.
The GetQuinticControlVectorsFromWaypoints() method was removed because it is not possible for us (or
would require breaking changes to the shape of the splines) to generate only one quintic control vector
per Pose2d. Users who actually have control vectors directly (i.e. not from Pose2d objects, but a
dashboard such as PathWeaver) should have the number of control vectors correspond to the number of
"waypoints" and can call GetQuinticSplinesFromControlVectors() directly.
This includes physics simulation support for arms/elevator models, as well as differential drivetrains.
Swerve might be added at a later date.
Co-authored-by: Claudius Tewari <cttewari@gmail.com>
Co-authored-by: Prateek Machiraju <prateek.machiraju@gmail.com>
Co-authored-by: Tyler Veness <calcmogul@gmail.com>
This helps reduce compilation overhead. I tried slimming down includes
of <Eigen/QR>, but the householderQr() function we use from there
requires including dependency headers from Eigen that don't fit with
lexographic ordering. It didn't seem worth the effort to work around.
This won't affect user code at all since all the Eigen feature usage
here is internal only; users generally only need <Eigen/Core>.
It was added as part of Bryson's rule described in
https://file.tavsys.net/control/controls-engineering-in-frc.pdf. It
doesn't really simplify usage though, and the same thing can be
replicated by multiplying the elements of Q by rho manually. It's easier
to do it that way, it's how 3512 has been doing controller debugging for
a while, and it's probably what other teams will do as well instead of
using the "more structured" way.
Removing these unhelpful overloads also simplifies the LQR interface.
I didn't notice a performance difference between the original
implementation and this one for a flywheel simulation, so this
simplifies a lot of internals.
This class can no longer implement KalmanTypeFilter because that class
allows setting the error covariance for use in the
KalmanFilterLatencyCompensator class. This won't impact the holonomic pose
estimators that use KalmanFilterLatencyCompensator because they all use an EKF.
The wpimath library is a new library designed to separate the reusable math functionality
from the common utility library (wpiutil) and the hardware-dependent library (wpilibc/j).
Package names / include file names were NOT changed to minimize breakage. In a future year
it would be good to revamp these for a more uniform user experience and to reduce the risk
of accidental naming conflicts.
While theoretically all of this functionality could be placed into wpiutil, several pieces
of this library (e.g. DARE) are very time-consuming to compile, so it's nice to avoid this
expense for users who only want cscore or ntcore. It also allows for easy future separation
of build tasks vs number of workers on memory-constrained machines.
This moves the following functionality from wpiutil into wpimath:
- Eigen
- ejml
- Drake
- DARE
- wpiutil.math package (Matrix etc)
- units
And the following functionality from wpilibc/j into wpimath:
- Geometry
- Kinematics
- Spline
- Trajectory
- LinearFilter
- MedianFilter
- Feed-forward controllers
