function clearPath()
  redstone.setOutput("left", true)
  sleep(1)
  redstone.setOutput("left", false)
end

function forward()
  clearPath()
  redstone.setOutput("front", true)
  sleep(1)
  redstone.setOutput("front", false)
end

function breaker()
  redstone.setOutput("back", true)
  sleep(3)
  redstone.setOutput("back", false)
end

for k,v in pairs(redstone.getSides()) do
  print (v)
end

while true do
  breaker()
  forward()
  sleep(5)
end