In this work a new algorithm is derived for the onboard calibration of three-axis strapdown magnetometers. The proposed method written in sensor frame, and compensates combined effect all linear time-invariant distortions, namely soft iron, hard nonorthogonality, bias, among others. A maximum likelihood estimator (MLE) formulated to iteratively find optimal parameters that best fit readings, without requiring external attitude references. It shown technique equivalent estimation rotation,...

This brief presents an embedded vehicle dynamics (VD) aiding technique to enhance position, velocity, and attitude error estimation in low-cost inertial navigation systems (INSs), with application underwater vehicles. The model of the VD provides motion information that is complementary INS and, consequently, fusion both allows for a comprehensive improvement overall system performance. In this brief, specific equations are directly extended Kalman filter, as opposed classical external...

This paper develops a navigation system based on complementary filtering for position and attitude estimation, with application to autonomous surface crafts. Using strapdown inertial measurements, vector observations, global positioning (GPS) aiding, the proposed filters provide estimates in Euler angles representation Earth frame coordinates, while compensating rate gyro bias. Stability performance properties of under operating conditions usually found oceanic applications are derived,...

This paper addresses the design, analysis, and validation of safe close-proximity operations around uncooperative targets, with an application to ClearSpace-1 (CS-1) mission. It is focused on areas Guidance, Navigation, Control (GNC), Mission Analysis, due their criticality for success safety this kind operation. The relevance concepts, GNC solutions, demonstrated case study CS-1, a reference mission rendezvous, capture, de-orbiting target (i.e., VESPA payload adapter). shown how design...

This paper presents a new ultra-short baseline (USBL) tightly-coupled integration technique to enhance error estimation in low-cost strap-down inertial navigation systems (INSs) with application underwater vehicles. In the proposed strategy acoustic array spatial information is directly exploited resorting extended Kalman filter implemented direct feedback structure. The determination and stochastic characterization of round trip travel time are obtained pulse detection matched filters...

This work proposes a position and attitude nonlinear observer based on inertial measurements GPS pseudorange readings. The observation problem is formulated SE(3), the solution yields exponential convergence of estimates. sensor readings are exploited directly in observer, integration vector discussed. proposed dynamics compensate for bias angular velocity clock offset measurements. stability estimates presence bounded accelerometer noise also analyzed. properties GPS/IMU illustrated...

This work proposes a nonlinear observer for position and attitude estimation on SE(3). Using Lyapunov function based the landmark measurement error, almost global exponential stability (GES) of desired equilibrium points is obtained. It shown that derived feedback law an explicit measurements velocity readings, geometry characterizes asymptotic convergence closed loop system solution. Almost stabilization in presence biased readings also achieved. Simulation results trajectories described by...

This paper presents a high-accuracy, multirate inertial navigation system (INS) integrating global positioning (GPS) measurements and advanced vector aiding techniques for precise position attitude estimation of autonomous surface crafts (ASCs). Designed to be implemented tested in the DELFIMx catamaran developed at ISR/IST, comprises an integration algorithm account coning sculling motions, combined with extended Kalman filter (EKF) sensor error compensation. Aiding gravitational...

This paper presents an experimentally evaluated solution to the problem of estimating attitude a rigid body using rate gyros and pan-tilt camera. A nonlinear observer combines angular velocity measurements obtained from with images planar scene provided by By directly exploiting sensor information, stabilizing feedback law is introduced, exponential convergence origin estimation errors shown. Additionally, active-vision system proposed that relies on image-based exponentially...

This paper presents the development of an attitude complementary filter for and heading reference system (AHRS). Using strapdown inertial measurements vector observations, proposed provides estimates in Euler angles representation, while compensating rate gyro bias. Stability performance properties under operating conditions usually found oceanic applications are derived, tuning parameters frequency domain is emphasized. The solution poses small computational requirements, suitable...

Lyapunov methods and density functions provide dual characterizations of the solutions a nonlinear dynamic system. This work exploits idea combining both techniques, to yield stability results that are valid for almost all Based on combination functions, analysis proposed derivation input-to-state stability, global in systems. The techniques illustrated an inertial attitude observer, where angular velocity readings corrupted by non-idealities.

The ESA Lunar Lander mission is a step in the preparation for future exploration missions, being tasked with demonstrating autonomous soft, safe precision landing on Moon. last segment of mission’s descent and phase approach phase, during which GNC subsystem steers spacecraft to targeted site (LS). Hazard Detection Avoidance (HDA) active this uses measurements provided by camera LIDAR assess safety terrain. HDA also determines are ground locations that can be reached spacecraft. Based...

Abstract We present a non‐trivial case study designed to highlight some of the practical issues that arise when using mixed‐µ or complex‐µ robust synthesis methodologies. By considering multi‐input multi‐output three‐cart mass–spring–dashpot (MSD) with uncertain parameters and dynamics, it is demonstrated optimized performance (disturbance‐rejection) reduced as level uncertainty in one two real increased. Comparisons are made (a) frequency domain, (b) by RMS values key signals (c)...

This paper proposes an aiding technique to enhance error estimation in low-cost strapdown inertial navigation systems with application Unmanned Air Vehicles (UAVs). The summarizes a high-accuracy, multi-rate integrated Global Positioning System/Inertial Navigation System (GPS/INS) using Extended Kalman Filter (EKF) for compensation. A proposed new decomposes and optimally integrates the magnetic gravitational observations EKF, taking into account vehicle’s dynamics bandwidth information...

This work evaluates the impact of two state-of-the-art aiding techniques to enhance performance inertial navigation systems (INS). A new embedded methodology integrate vehicle dynamics (VD) in system is proposed, by modeling it directly Extended Kalman Filter. The VD and INS algorithm propagate simultaneously states, allowing for estimation errors exploiting dynamical information enclosed model. Results show that attitude, velocity sensors bias estimates are enhanced comprehensive number...

This paper addresses the problem of detecting and isolating faults in angle-of-attack (AoA) measurements, when faulty sensors outnumber healthy ones. Such a scenario hinders applicability heuristic-based techniques, such as voting schemes. Rather than including additional sensors, which would increase payload system complexity, solution adopted herein takes advantage knowledge on dynamics aircraft, modeled by linear fractional transformation (LFT), to detect isolate faults. approach is used...

This paper presents a nonlinear observer for attitude estimation on SO(3) and studies the stability properties of system in presence nonideal inertial sensor measurements. Exploiting vector observations biased angular velocity readings feedback law, almost global asymptotic origin is obtained exponential convergence guaranteed an explicit region state space. Sufficient conditions design are proposed to yield given worst-case initial alignment errors. Stability measurement noise obtained,...