Group measurement method flatness detection apparatus

The invention discloses a group measurement method flatness detection apparatus. A frame is provided with a workpiece adaptive compaction mechanism, and a detection positioning device which horizontally moves in a predetermined direction along a guide rail. The frame is provided with a fixedly-mounted group measurement sensor set. The group measurement sensor set comprises more than three LVDT sensor groups. The group measurement sensor set is fixed on the frame through a sensor installation plate. The sensor installation plate is provided with a three-point positioning mechanism and a spacing mechanism. The detection positioning device is provided with a detected workpiece. The detected workpiece can horizontally slide on the positioning device in the guide rail direction. The workpiece adaptive compaction mechanism drives a positioning block through a cylinder and the like. The detection positioning device positioning block is provided with more than three positioning push needles not on the same straight line. The positioning push needles are sleeved by spring adaptive mechanisms. The invention can reduce the labor cost in the brake disc flatness detection, and improves the measurement accuracy and the working efficiency.