Based on briefly analyzing work characters of present lightweight automaticholemakingsystem and operational demands of aircraft wingtobody connection, a new holemaking system with serialparallel mechanism was proposed for generating holes in the suspended panel. According to the double requirements of center alignment and posture alignment, a normal posture alignment mechanism with five degrees of freedom was designed, then a detector for online measuring normal vector of the holes central line was developed which is composed of one image sensor and three laser displacement sensors. With the precision analysis and motion simulation of normal posture alignment mechanism, the research results applied to engineering practice was feasibly verified.