struct Sc
  mass::Float64
  mass_flow_rate::Float64
  max_thrust::Float64
  num_thrusters::Int
  duty_cycle::Float64
end

function Sc(name::String)
  if name == "test"
    return Sc(1000., 0.01, 0.1, 2, 1.)
  elseif name == "no_thrust"
    return Sc(1000., 0.01, 0., 0, 0.)
  else
    throw(ErrorException("Bad sc name"))
  end
end