A common issue with many system identification problems is that the true input to unknown. This paper extends a previously presented indirect modelling framework deals of systems where partially or fully In this framework, unknown inputs are eliminated by using additional measurements directly indirectly contain information about inputs. The resulting predictor model only dependent on known and measured signals can be used estimate desired dynamics properties. Since contains both could all...

The task of maneuvering ships in confined environments is a difficult for human operator. One major reason due to the complex and slow dynamics ship which need be accounted order successfully steer vehicle. In this work, two-step optimization-based motion planner proposed autonomous constrained such as harbors. A lattice-based used first step compute feasible, but suboptimal solution discretized version planning problem. This then enable efficient warm-start terminal manifold second...

In this paper, an approach to estimate the mass of a quadcopter using only inertial measurements and pilot commands is presented. For purpose, lateral dynamic model describing relation between roll rate acceleration formulated. Due quadcopter's inherent instability, controller used stabilize system data collected in closed loop. Under effect feedback disturbances, as input output are correlated with which complicates parameter estimation. The parameters estimated several methods. simulation...

The interest for system identification in dynamic networks has increased recently with a wide variety of applications. In many cases, it is intractable or undesirable to observe all nodes network and thus, estimate the complete dynamics. Furthermore, might even be challenging subset if key are unobservable due correlation between nodes. this contribution, we will discuss an approach treat problem. relies on additional measurements that dependent thus indirectly contain information about...

For future autonomous marine vessels, better understanding of the ship's behavior and control performance will be essential. Traditional motion systems for ships decouple problem into high-level ship thrust allocation to achieve desired action through available actuators. The benefit is a segmented software, aiding in development commissioning. drawback this decoupling that controller at best has an approximate model capabilities thruster system. This typically leads mismatch between...

In this paper, an instrumental variable (IV) method for estimating the mass and center of (CM) a ship using IMU data has been further investigated. Here, IV method, which was proposed in earlier analyzed from closed-loop point view. This new perspective reveals properties system dependencies signals used estimation procedure. Due to similarities with identification, previous results identification field have as inspiration improve estimator. Since roll dynamics is well described by pendulum...

A ship's roll dynamics is sensitive to the mass and distribution. Changes in these physical properties might introduce unpredictable behavior of ship a worst-case scenario that will capsize. In this paper, recently proposed approach for online estimation center validated using experimental data. The experiments were performed scale model wave basin. data collected free run where rudder angle was recorded motion measured an inertial measurement unit. measurements are used conjunction with...

A ship's roll dynamics is very sensitive to changes in the loading conditions and a worst-case scenario loss of stability. This paper proposes an approach for online estimation mass center mass. Instead focusing on sensor-rich environment where all possible signals ship can be measured complete model estimated, minimal adopted. derived from well-established literature it assumed that only motion measurements inertial measurement unit together with rudder angle are available. Furthermore,...

In this work, we estimate a model of the vertical dynamics quadcopter and explain how can be used for mass estimation diagnosis system changes. First, standard thrust describing relation between calculated control signals rotors that is commonly in literature estimated. The results are compared to those using refined it turns out gives significant improvement. combination nonlinear closed-loop data poses some challenges shown an instrumental variables approach obtain accurate estimates....

An enabling technology for future sea transports is safe and energy-efficient autonomous maritime navigation in narrow environments with other marine vessels present. This requires that the algorithm controlling ship able to account vessel's dynamics, obeys rules specified international regulations preventing collision at (COLREGs). To these properties, this work proposes a two-step optimization-based COLREGs-compliant motion planner tailored large vessels. In first step, lattice-based used...

In this work, experiment design for marine vessels is explored. A dictionary-based approach used, i.e., a systematic way of choosing the most informative combination independent experiments out predefined set candidates. This idea quite general but here tailored to an instrumental variable (IV) estimator with zero-mean instruments. type well-suited deal parameter estimation second-order modulus models, which class models often used describe motion vessels. The method evaluated using both...

In this work, experiment design for marine vessels is explored. A dictionary-based approach used, i.e., a systematic way of choosing the most informative combination independent experiments out predefined set candidates. This idea quite general but here tailored to an instrumental variable (IV) estimator with zero-mean instruments. type well-suited deal parameter estimation second-order modulus models, which class models often used describe motion vessels. The method evaluated using both...

A common issue with many system identification problems is that the true input to unknown. In this paper, a framework, based on indirect measurements, proposed solve problem when partially or fully unknown, and cannot be measured directly. The approach relies measurements indirectly contain information about unknown input. resulting model formulation, both direct as inputs, can used estimate desired of original system. Due similarities closed-loop identification, an iterative instrumental...

In this paper, multi-objective optimization is applied to the hot rolling process. It modeled mostly using first principle models considering, for instance, mass balance (or flow rate), tensions in material, power requirements, thermal field, and microstructure of material.