pid_controller

A PID (proportional/integral/derivative) controller in Elixir. “PID” in this context is not to be confused with process ID.

QUICK START

controller =
  PidController.new(kp: 0.2, ki: 0.1)
  |> PidController.set_setpoint(5.0)

# in a loop
{:ok, output, controller} = PidController.output(input, controller)

OVERVIEW

PidController implements a control loop-style feedback controller similar to what is commonly found in industrial control systems. It takes a measured value from the system under control (the process value or process variable), compares it to a setpoint value to produce an error term, then generates a control value based on proportional, integral, and derivative functions of the error term. The control value is then fed back into the system under control.

Detailed documentation is available at https://craigcottingham.github.io/pid_controller/.

INSTALLATION

Add pid_controller to your list of dependencies in mix.exs:

def deps do
  [
    {:pid_controller, "~> 0.1.3"}
  ]
end

Don’t forget to run mix deps.get afterwards.

USAGE

Documentation can be found at https://hexdocs.pm/pid_controller or https://craigcottingham.github.io/pid_controller/hexdocs.

CONTRIBUTING

1. Clone the repository.
2. Install dependencies with mix deps.get.

Pull requests are welcome. Pull requests with specs covering the changes are especially welcome. Pull requests with specs, which have been run through mix format, and pass mix credo are extra-especially welcome. 😄

Unit tests were written with ESpec.

TO DO

See the open issues on Github.

COPYRIGHT

Copyright (c) 2019-2020 Craig S. Cottingham, except where stated otherwise.

LICENSE

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.