Shape correction technique for stabilizing and linearizing a constant acceleration Mössbauer velocity drive

In a Mössbauer effect spectrometer employing a large vibrating mass or stiff drive centering springs, it is sometimes difficult to achieve satisfactory velocity tracking. In such situations, the linearity and stability of a constant acceleration Mössbauer velocity drive can be improved significantly by inserting a correction signal into the feedback loop. A simple physical interpretation of a shape correction technique is discussed, and a drive amplifier using this principle is described. This system has less than 0.1% tracking error over the velocity range +/-2 cm/s, yet the feedback gain is reduced by a factor of 60 as compared to a conventional drive.