penetration force, work
Needles are differentiated by their size, which is quantified with the gage value. A higher gage corresponds to a smaller diameter needle. It is well known that smaller needles penetrate the skin more easily. A method was developed to quantify the difference in force and work of penetration of a range of needle sizes. Three sizes of needles were purchased at a local medical supply store and tested with the TA.XTPlus Texture Analyzer.