MONITORING MILK FLOW AS AN AID TO MANAGEMENT IN AUTOMATIC MILKING SYSTEMS

The milking of animals in automatic milking systems requires the devel opment of sensor-based feedback control. This paper proposes the use o f milk flow as a method of monitoring the correct performance of the m ilking machine and examines the repeatability of this measure through lactation. The milk flow was defined by the let down time (the time fr om attachment of teat cups until a steady flow of milk begins), the pe ak flow rate and the stripping time. Peak flow rate was the rate at wh ich the first 75% of milk was extracted. Stripping time was the time t o extract the last 25% of milk removed. The milk flow profile of four goats was recorded at morning and evening milking once each week for 3 0 weeks. The mean let down time was constant throughout lactation at 1 2.1 s (S.D. 0.45 s), while the mean stripping time was 25.7 s (S.D. 7. 76 s) indicating the variability of milk flow towards the end of milki ng. Peak milk flow for individual animals varied little throughout lac tation. A method of deriving peak flow rate automatically was develope d and this can be used to check that milking is progressing correctly.