PID Controllor for Hypnotizd's Reactor Controller

controllor.lua

----------------------------------------------------------
-- Active Cooling Big Reactor Monitor                   --
--                                                      --
-- Minecraft HermitCraft FTB Infinity Episode 28        --
-- https://www.youtube.com/watch?v=cIPxwZJWOiE          --
--                                                      --
-- YouTube Channel http://youtube.com/hypnotizd         --
--                                                      --
-- Add PID Algorithm By AKFish                          --
-- https://github.com/akfish                            --
-- https://catx.me                                      --
----------------------------------------------------------

local mon = {}
local hasMon = false
local hasRMon = false
local rMonName = ""
local cPort = {}
local hasCPort = false
local hasRCPort = false
local rCPortName = ""
local directions = {"top", "bottom", "front", "back", "left", "right"}
local minX = 0
local minY = 0
local minZ = 0
local maxX = 0
local maxY = 0
local maxZ = 0
local crPrevCoreTemp = 0
local crCoreTemp = 0
local crCoreChangeWait = 0

-- PID Controllor Factory
-- @author AKFish
-- @reference http://en.wikipedia.org/wiki/PID_controller
-- @param target - Desired process variable (i.e. reactor temprature) value
-- @param k_p - Proportional gain
-- @param k_i - Integral gain
-- @param k_d - Derivative gain
-- @return a function that calculates controllor output (delta for the manipulated variable, i.e. rod position)
local function PID(target, k_p, k_i, k_d)
  local previouseError = 0
  local integral = 0
  local dt = 1
  return function (measured)
    local error = target - measured
    previouseError = error
    integral = integral + error * dt
    local derivative = (error - previouseError) / dt
    return k_p * error + k_i * integral + k_d * derivative
  end
end

local targetCoreTemperature = 10000000 -- Or maybe something not that hot
-- The following parameters need to be fine tuned for optimal results
-- See http://en.wikipedia.org/wiki/PID_controller#Manual_tuning
local k_p = 0.1
local k_i = 0.1
local k_d = 0.1
-- The controllor instance
-- Note: this instance stores internal states of the controllor and 
--       should be recreated when any of the parameters 
--       or initial conditions are changed 
local pid = PID(targetCoreTemperature, k_p, k_i, k_d)

local function findPeripherals()
  for k, v in pairs(peripheral.getNames()) do
    if string.find(v, "Reactor") then
      hasCPort = true
      hasRCPort = true
      rCPortName = v
      print("INFO: Found remote "..v)
      os.sleep(1)
    elseif string.find(v, "monitor") then
      hasMon = true
      hasRMon = true
      rMonName = v
      print("INFO: Found remote "..v)
      os.sleep(1)
    end
  end
end

local function findCPort()
  if hasRCPort then return end
  for k, v in pairs(directions) do
    local p = peripheral.wrap(v)
    if p ~= nil then
      if string.find(peripheral.getType(v), "Reactor") then
        cPort = p
        hasCPort = true
        return
      end
    end
  end
  print("ERROR: No computer port detected!")
end

local function findMon()
  if hasRMon then return end
  for k, v in pairs(directions) do
    local p = peripheral.wrap(v)
    if p ~= nil then
      if string.find(peripheral.getType(v), "monitor") then
        mon = p
        hasMon = true
        return
      end
    end
  end
  print("WARNING: No monitor detected!")
  os.sleep(5)
end

local function monClear()
  if hasMon then
    if hasRMon then
      peripheral.call(rMonName, "setCursorPos", 1, 1)
      peripheral.call(rMonName, "clear")
    else
      mon.setCursorPos(1, 1)
      mon.clear()
    end
  else
    term.clear()
    term.setCursorPos(1, 1)
  end
end

local function monWrite(x, y, text)
  if hasMon then
    if hasRMon then
      peripheral.call(rMonName, "setCursorPos", x, y)
      peripheral.call(rMonName, "write", text)
    else
      mon.setCursorPos(x, y)
      mon.write(text)
    end
  else
    term.setCursorPos(x, y)
    term.write(text)
  end
end

local function getSize()
  if hasRCPort then
    minX, minY, minZ = peripheral.call(rCPortName, "getMinimumCoordinate")
    maxX, maxY, maxZ = peripheral.call(rCPortName, "getMaximumCoordinate")
  else
    minX, minY, minZ = cPort.getMinimumCoordinate()   
    maxX, maxY, maxZ = cPort.getMaximumCoordinate()
  end
end

local function setAllControlRodLevels(x)
  if hasRCPort then
    peripheral.call(rCPortName, "setAllControlRodLevels", x)
  else
    cPort.setAllControlRodLevels(x)
  end
end

local function getActive()
  local ret = false
  if hasRCPort then
    ret = peripheral.call(rCPortName, "getActive")
  else
    ret = cPort.getActive()
  end
  return ret
end

local function getControlRodLevel()
  local ret = 0
  if hasRCPort then
    ret = peripheral.call(rCPortName, "getControlRodLevel", 0)
  else
    ret = cPort.getControlRodLevel(0)
  end
  return ret
end

local function getFuelTemperature()
  local ret
  if hasRCPort then
    ret = peripheral.call(rCPortName, "getFuelTemperature")
  else
    ret = cPort.getFuelTemperature()
  end
  return ret
end

local function setControlRods()
  if getActive() then
    crCoreTemp = getFuelTemperature()
    local delta = pid(crCoreTemp)
    local ctrlRodLevel = getControlRodLevel()
    -- Note: Higher than desired temperature yeilds negative delta and vice versa
    --       Higher rod level cools it down more/faster, use negative sign
    --       (If higher rod level cools it down less/slower, use plus sign)
    local newRodLevel = ctrlRodLevel - delta
    -- TODO: clamp the newRodLevel value into the correct range
    setAllControlRodLevels(newRodLevel)
  end
end

local function init()
  term.clear()
  term.setCursorPos(1, 1)
  findPeripherals()
  findCPort()
  findMon()
  getSize()
  monClear()
end

local function displayInfo()
  local rods = 0
  local casingTemp = 0
  local coreTemp = 0
  local rodLevel = 0
  local fuelReactivity = 0
  local fuelConsumed = 0
  local steamProduced = 0
  
  if hasRCPort then
    rods = peripheral.call(rCPortName, "getNumberOfControlRods")
    casingTemp = peripheral.call(rCPortName, "getCasingTemperature")
    coreTemp = peripheral.call(rCPortName, "getFuelTemperature")
    rodLevel = peripheral.call(rCPortName, "getControlRodLevel", 0)
    fuelReactivity = peripheral.call(rCPortName, "getFuelReactivity")
    fuelConsumed = peripheral.call(rCPortName, "getFuelConsumedLastTick")
    steamProduced = peripheral.call(rCPortName, "getHotFluidProducedLastTick")
  else
    rods = cPort.getNumberOfControlRods()
    casingTemp = cPort.getCasingTemperature()
    coreTemp = cPort.getFuelTemperature()
    rodLevel = cPort.getControlRodLevel(0)
    fuelReactivity = cPort.getFuelReactivity()
    fuelConsumed = cPort.getFuelConsumedLastTick()
    steamProduced = cPort.getHotFluidProducedLastTick()
  end
  
  local active = "Inactive"
  if getActive() then
    active = "Active"
  end
  
  monClear()
  monWrite(1, 1, "   Reactor Status: "..active)
  monWrite(1, 2, "     Reactor Size: "..1+maxX-minX.."x"..1+maxY-minY.."x"..1+maxZ-minZ)
  monWrite(1, 3, " Num Control Rods: "..rods)
  monWrite(1, 4, "     Casing Temp.: "..casingTemp)
  monWrite(1, 5, "       Core Temp.: "..coreTemp)
  monWrite(1, 6, "Control Rod Level: "..rodLevel)
  monWrite(1, 7, "  Fuel Reactivity: "..fuelReactivity)
  monWrite(1, 8, "  Fuel Usage/tick: "..fuelConsumed)
  monWrite(1, 9, "   Steam Produced: "..steamProduced)
end

init()
if hasCPort == false then return end

while true do
  setControlRods()
  displayInfo()
  os.sleep(3)
end