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1

Validation of the energy consumption model for a quadrotor using Monte-Carlo simulation

Głębocki Robert, Żugaj Marcin, Jacewicz Mariusz

Archive of Mechanical Engineering

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2023

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LXX, nr 1

151–-178

EN

Unmanned, battery-powered quadrotors have a limited onboard energy resources. However, flight duration might be increased by reasonable energy expenditure. A reliable mathematical model of the drone is required to plan the optimum energy management during the mission. In this paper, the theoretical energy consumption model was proposed. A small, low-cost DJI MAVIC 2 Pro quadrotor was used as a test platform. Model parameters were obtained experimentally in laboratory conditions. Next, the model was implemented in MATLAB/Simulink and then validated using the data collected during real flight trials in outdoor conditions. Finally, the Monte-Carlo simulation was used to evaluate the model reliability in the presence of modeling uncertainties. It was obtained that the parameter uncertainties could affect the amount of total consumed energy by less than 8% of the nominal value. The presented model of energy consumption might be practically used to predict energy expenditure, battery state of charge, and voltage in a typical mission of a drone.

2

Use of Wind Tunnel Measurements Data in Cold Launched Missile Flight Simulations

Ożóg Rafał, Jacewicz Mariusz, Głębocki Robert

Pomiary Automatyka Robotyka

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2020

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R. 24, nr 1

49--60

EN

This article presents the results of wind tunnel testing of a model of a missile intended for a vertical cold launch system. The objective of this work was to obtain nondimensional aerodynamic coefficients to build a lookup table database for a six-degree-of-freedom numerical simulation of the missile launch phase. The material model of the full-scale missile was designed in UG/NX Siemens software and manufactured. Low speed measurements were conducted at the Warsaw University of Technology and as a result, static forces and moments characteristics were obtained using six component internal balance for a wide range of angles of attack and sideslip with a 1° interval. Finally, 200 Monte-Carlo simulations in MATLAB/Simulink were evaluated to investigate the missile behavior in the launch phase with the measured results. It was observed that the rolling moment resulting, i.a. from fin cant angles misalignments in the initial roll rate of the missile significantly affects the trajectories.

PL

Niniejszy artykuł przedstawia wyniki testów w tunelu aerodynamicznym modelu rakiety dedykowanej dla pionowego zimnego startu. Celem pracy było uzyskanie bezwymiarowych współczynników aerodynamicznych potrzebnych do opracowania bazy w postaci tablic dla numerycznej symulacji lotu o sześciu stopniach swobody. Model materialny pełnowymiarowej rakiety został zaprojektowany przy wykorzystaniu programu Siemens UG/NX. Testy zostały przeprowadzone na Politechnice Warszawskiej przy niskiej prędkości przepływu a charakterystyki statycznych sił i momentów uzyskano za pomocą sześcioskładnikowej wagi wewnętrznej dla szerokiego zakresu kątów natarcia i ślizgu z krokiem 1°. Ostatecznie, przeprowadzono 200 symulacji Monte-Carlo w programie MATLAB/Simulink w celu zbadania zachowania pocisku w fazie startu z użyciem zmierzonych wartości. Zostało zaobserwowane, że moment przechylający wynikający m.in. z niedokładności montażowych stabilizatorów wpływa znacząco na uzyskiwane trajektorie.

3

Modified trajectory tracking guidance for artillery rocket

Ożóg Rafał Józef, Jacewicz Mariusz Adam, Głębocki Robert

Journal of Theoretical and Applied Mechanics

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2020

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Vol. 58 nr 3

611--622

EN

This paper contributes to a modified guidance scheme based on a trajectory tracking method which is dedicated for an artillery rocket with a finite set of single use solid propellant side thrusters. Frequency modulation of pulses was used to achieve effective firing logic. The proposed control law is applicable in the last phase of flight when the rocket reaches the vertex of the trajectory. A correction engine activation sequence was chosen in such a way that possibility of rocket axial unbalance is minimized due to motors firing. Numerical simulation results indicate that significant dispersion reduction was achieved and the number of activated side rocket thrusters is minimized.

4

Impact point prediction guidance parametric study for 155 mm rocket assisted artillery projectile with lateral thrusters

Szklarski Adrian, Głębocki Robert, Jacewicz Mariusz

Archive of Mechanical Engineering

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2020

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LXVII, nr 1

31--56

EN

The modified configuration of the 155 mm rocket assisted projectile equipped with lateral thrusters was proposed. Six degree of freedom mathematical model was used to investigate the quality of the considered projectile. Impact point prediction guidance scheme intended for low control authority projectile was developed to minimize the dispersion radius. Simple point mass model was applied to calculate the impact point coordinates during the flight. Main motor time delay impact on range characteristics was investigated. Miss distance errors and Circular Error Probable for various lateral thruster total impulse were obtained. Monte-Carlo simulations proved that the impact point dispersion could be reduced significantly when the circular array of 15 solid propellant lateral thrusters was used. Single motor operation time was set to be 0.025 s. Finally, the warhead radii of destruction were analyzed.