A Force Measurement System for Missile Guidance Control Using Jet Vanes

To determine the forces and moments on movable jet vanes immersed into the exhaust flame of a large solid rocket motor, and to determine the resultant forces and moments upon the motor-missile configuration, two multi-component internal strain-gage floating-frame balances were designed and integrated into the vane actuation systems. These balances provided an accurate, economical, trouble-free multi-component force measurement system which was readily integrated into an existing static motor firing program. The combined average error of the balance data is within ±5.5% for a 99.7% confidence interval. A 1401 computer program based upon equivalent in-place balance calibration results was prepared to reduce the static motor firing data parameters to engineering units. The design and calibration considerations for a specialized balance design and general design considerations for all multi-component force measurement systems are discussed in this paper.