Design of a High Angle of Attack Robotic Sting Mount for Tests in a Low Speed Wind Tunnel.

摘要

A sting mounting system designed for high angle of attack (AOA) testing has been developed for the 7x10 foot low-speed wind tunnel (LSWT). The mechanism was able to position the model from -15 deg to +90 deg of pitch with accuracy to within 0.2 deg, while keeping the model near the center of the test section. Compatible with the current turntable apparatus, the high angle of attack robotic sting (HARS) retained the turntable's full range of yaw movement of + or - 90 deg. All model positioning was done without shutting the tunnel down to manually alter the sting or mounting apparatus. Pitch adjustment progressed at about 4 deg per second, with final position tuning taking nearly 15 seconds. The mechanism consisted of two square steel telescoping tube struts that were joined at the ends in the test section by a cross link that held the existing LSWT small Langley sting. Wind tunnel blockage and flow irregularities near the model were minimized by mounting drive hardware under the tunnel floor. An IBM/AT compatible microcomputer equipped with an analog-to-digital conversion board provided position control, drive motor signaling, and input signal filtering. Theses. (jhd)