I tested it and the problem is that the result is not constant wrong.
for example: the right length is 37cm -> result of srf02: 27cm
27cm -> result of srf02: 25cm
I tested it and the problem is that the result is not constant wrong.
for example: the right length is 37cm -> result of srf02: 27cm
27cm -> result of srf02: 25cm