Open loop Scale Etc PUBLIC

Graphing a simple equation of motion.

Distance = u*t + 0.5*a*t^2

Equation scaling (reality) = (simulation):-

1 unit distance (arbitrarily, 1 meter) = 1volt (at displacement output)

1 unit of time (Second) = 10mS (set by R1xC1 = R2xC2)

Speed, 1meter/sec = 1volt/10mS (at output of acceleration integrator), OA1)

Acceleration, 1 meter/sec/sec = 10uA= 1volt/10mS across 100nF

For ExploreAnalog

UPDATE 8th Aug 2020 i) correct spring constant definition; ii) add details of scaling factors for equation constants.

In relation to the weight-with-spring example. Xdouble-dot - Xdot + X = 0 (then constant)

The differential equation has unity scaling: all multiplying constants are "1". This works well with the SI unit definitions, for example:

Force: 1 Newton = 1 meter/sec/sec X 1 kg

For other parts of the simulation:

Mass 1kg = 100nF at acceleration integrator, OA1 AND pot R9, 1/K = 1 (NB reciprocal)

Spring constant, unit force for unit extension (1 Newton per meter) = 1 = 10uA/volt in R1

Loss, unit force for unit speed (1 Newton per meter/sec) = 1 when pot R8 K=1

Leverage - displacement multiplier (not shown) related to R10's K value.