Hi,
H(igh) L(evel) F(eed) B(ack). Its in the manual, it is the fault signal line FROM the servo TO your
controller.
'In Position' is the same intent as 'Following Error', it indicates whether the servo can keep up,if it can't
follow its commanded input, or as Clearpath put it, stay 'In Position' then it will send a fault signal to Mach.
You will need to know all about it if you are going to use Clearpath servos.
Craig