To achieve high Strapdown Inertial Navigation System (SINS) alignment accuracy within a short period of time is still a challenging issue for underwater vehicles. In this paper, a new SINS initial alignment scheme aided by the velocity derived from Doppler Velocity Log (DVL) is proposed to solve this problem. In the stage of the coarse alignment, the velocity of DVL is employed to reduce the im...

Dislocation following total hip replacement surgery (THR) remains a significant clinical problem. Malposition of the acetabular component increases the occurrence of impingement, reduces the " safe " range of motion and increases the risk of dislocation. Not fully understanding the interaction between pelvic orientation and final acetabular cup alignment may be one of the main contributing fact...

For aircrafts equipped with BeiDou Navigation Satellite System/Strapdown Inertial System integrated navigation system, information can be used to achieve autonomous alignment. However, due the complex polar environment and multipath effect, measurement noise often exhibits a non-Gaussian distribution that will severely degrade estimation accuracy of standard Kalman filter. To address this probl...

Abstract. A heave compensation system is one of the absolutely necessary instruments to secure mining operation. The heave compensation system includes a heave compensated platform which is to compensate heave motion and a gimbaled platform which is to accommodate pitch and roll. The simulation of a nonlinear model based on fuzzy PID control is performed. The results show that the compensation ...

We adopted a new computed tomography (CT)-free navigation system and noticed that, compared with our previous experience using a different type of CT-free navigation system that led to oversized and extended femoral component implanted compared with the conventional implantation, the femoral components were similarly implanted to the conventional method. The purpose of our study was to compare ...

Through assembling the navigation parameters as matrix Lie group state, corresponding inertial system (INS) kinematic model possesses a group-affine property. The logarithm of state estimation error satisfies log-linear autonomous differential equation. These models are still applicable even with arbitrarily large initial errors, which is very attractive for INS alignment. However, in existing ...

following the idea of $l$-fuzzy neighborhood system as introduced byfu-gui shi, and its generalization to $(l,m)$-fuzzy neighborhood system, the relationship between  $(l,m)$-fuzzy topology and $(l,m)$-fuzzy neighborhood system will be further studied. as an application of the obtained results, we will describe the initial structures of $(l,m)$-fuzzy neighborhood subspaces and $(l,m)$-fuzzy top...