1. The problem statement, all variables and given/known data Hi, I have to do a simulation of two non linear dynamical equations which represent a electromechanical system. (An inverted pendulum attached to a cart moving over a rail). I am going to simulate the response via numerical methods programmed in LV. (I am trying firts with a variable step size RK.). I have 4 state variables [x,x_dot,theta,theta_dot] and Vm which is a voltage. 2. Relevant equations My question is that to avoid the propagation of numerical error during the simulation one have to properly set the dimensions according to the range of variation of the variables in order to set each variable range of variation to be [-1,+1]. If you put the x in meters, you have a range of variation of [-0.5,+0.5] or [0,1] because the rail is 1 meter long. (Also you may set that in cm or in mm, but this may led you to get more error during the iterative process of the simulation). Also he pendulum may rotate over the pivot for the full angle of rotation. If you set the angle (theta) in rads the range is [0,2*pi] but if you set this in degrees you then have [0,360]. The Voltage Vm could vary from 0 to 16 volts. 3. The attempt at a solution I am going to try first with X in meters and Theta in radians, Vm in volts.