1. The problem statement, all variables and given/known data The first order ramp unit response is shown in the graph below. Determine: 1. The transfer function. 2. Plot the error function e(t) then determine its maximum magnitude and the time http://s24.postimg.org/cdbhqm80j/Capture.png 2. Relevant equations G(s)=(1/T)/(S+1/T) ......... G(s): Standard first order T.F, , T (or tau) is the time constant. T is the time to reach 63,2% of the final output value. 3. The attempt at a solution I know how to solve this if the input was the step unit as shown in the graph: But that is not my case in ramp unit. How can I get the time constant while the curve is going upward forever? The only thing I knew that if I plot the error function, then its steady state value will be T (tau or time constatnt). Any help?