Track maintenance machine and measurement method for a track maintenance machine

A track maintenance machine, comprising:

• a frame having at least two axles and at least two wheels operatively connected to each said axle and configured to support the track maintenance machine on a track;
• a workhead arranged between said axles;
• a machine control system;
• a B point set at or near the workhead at a predetermined height above the track, and a C point set at a rear end of said frame in a movement direction of the track maintenance machine at a predetermined height above the track;
• a sensor arranged at a forward end of said frame in a movement direction of the track maintenance machine and at a predetermined height above the track;
• said sensor being configured to:
• scan forward of the track maintenance machine to identify an A point,
• acquire track data values for said A point, and
• transmit said track data values to said machine control system,
• said machine control system being configured to:
• calculate a chord by combining said track data values for said A point with said C point to calculate operation data for said workhead at said B point.