Error analysis and compensation of a strapdown inertial continuous surveying system

Gyroscopic surveying system utilizing one dual-axis dynamically tuned gyroscope and two accelerometers has been suggested to work at continuous mode to improve surveying efficiency. Investigation of how various error sources influence on the accuracy of the new continuous surveying system is helpful when finding ways to enhance the long-term performance. This article aims at analyzing the surveying errors associated with proposed continuous surveying algorithm, including algorithm errors, sensor errors, etc. The influence of each source on surveying result is formulated. It also offers some techniques to enhance the long-term surveying accuracy. The algorithm is modified to improve the toolface angle surveying accuracy. The biases of gyro and accelerometers are periodically modulated by continuous rotation. The modulated output signals are sampled and disposed, then surveying errors are reduced. Simulation results indicate that suggested methodology significantly improved the surveying accuracy.