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V. N. Likhachev

Bio: V. N. Likhachev is an academic researcher. The author has contributed to research in topics: Moon landing & Propulsion. The author has an hindex of 2, co-authored 5 publications receiving 11 citations.

Papers
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Journal ArticleDOI
TL;DR: An integrated conceptual basis is used to develop multistep terminal algorithms for guidance for the three segments of the descent of a landing module designed for the Moon landing.
Abstract: The paper deals with a choice of the rational trajectory of motion of a landing module designed for the Moon landing, from the moment of its de-orbiting from the near-lunar orbit up to landing. An integrated conceptual basis is used to develop multistep terminal algorithms for guidance for the three segments of the descent.

5 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present the braking profile of a spacecraft making a soft landing on the Moon's surface, including the following four phases: main braking, free fall, repeated braking and descent at a constant speed.
Abstract: Rationale is given for the braking profile of a spacecraft making a soft landing on the Moon’s surface, including the following four phases: main braking, free fall, repeated braking, and descent at a constant speed. Due to the large altitude differential over the braking path in near-polar regions of the Moon, main braking is proposed as a type of trajectory correction impulse using no altimeter. The boundary problem solution and statistical calculations are used to give the potential energy costs and characteristics of the dispersion characteristics for this phase and choose an optimal thrust-to-weight ratio for the phase.

4 citations

Journal ArticleDOI
TL;DR: In this paper, the main braking phase for a soft Moon landing as a form of trajectory correction was studied, and analytical relations for the main parameters were obtained, and the impact of various disturbing factors was estimated.
Abstract: This article continues our study of spacecraft guidance and control for a soft Moon landing (see our article “Main braking phase for a soft Moon landing as a form of trajectory correction”). Rationale is given for the objectives of the subsequent (final touchdown) phases. Analytical relations for the main parameters are obtained, and the impact of various disturbing factors is estimated. A methodology is proposed for calculating the main parameters for the whole braking sequence from the sighting altitude of the main braking phase termination to braking engine thrust and its throttle range.

4 citations

Journal ArticleDOI
TL;DR: For the descent from the pericenter of a prelanding circumlunar orbit a comparison of three algorithms for the control of lander motion is performed.
Abstract: For the descent from the pericenter of a prelanding circumlunar orbit a comparison of three algorithms for the control of lander motion is performed. These algorithms use various combinations of terminal and programmed control in a trajectory including three parts: main braking, precision braking, and descent with constant velocity. In the first approximation, autonomous navigational measurements are taken into account and an estimate of the disturbances generated by movement of the fuel in the tanks was obtained. Estimates of the accuracy for landing placement, fuel consumption, and performance of the conditions for safe lunar landing are obtained.

3 citations

Journal ArticleDOI
TL;DR: In this article, an algorithm was developed for terminal guidance during the main deceleration section of the lunar landing trajectory of a spacecraft with an integrated propulsion system, which has a main engine with variable thrust and four auxiliary nonthrottleable engines.
Abstract: An algorithm is developed for terminal guidance during the main deceleration section of the lunar landing trajectory of a spacecraft with an integrated propulsion system, which has a main engine with variable thrust and four auxiliary nonthrottleable engines. A method of guidance adaptation to the actual motion conditions by measuring the thrust acceleration with jumps in time is proposed.

Cited by
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Journal ArticleDOI
TL;DR: A novel double-loop guidance and control strategy for under-actuated lunar landers in terminal landing phases is developed by using adaptive nonlinear control approach and tuning rules for designing parameters in guidance law and attitude controller are derived based on the Lyapunov analysis.

4 citations

Journal ArticleDOI
TL;DR: For the descent from the pericenter of a prelanding circumlunar orbit a comparison of three algorithms for the control of lander motion is performed.
Abstract: For the descent from the pericenter of a prelanding circumlunar orbit a comparison of three algorithms for the control of lander motion is performed. These algorithms use various combinations of terminal and programmed control in a trajectory including three parts: main braking, precision braking, and descent with constant velocity. In the first approximation, autonomous navigational measurements are taken into account and an estimate of the disturbances generated by movement of the fuel in the tanks was obtained. Estimates of the accuracy for landing placement, fuel consumption, and performance of the conditions for safe lunar landing are obtained.

3 citations

Journal ArticleDOI
01 Feb 2021
TL;DR: A novel multi-stage trajectory transfer and fixed-point landing time optimal guidance method for the lunar surface emergency rescue mission is proposed and the whole time process guidance law is obtained by establishing the allowable control set for each stage in the whole process.
Abstract: In this paper, a novel multi-stage trajectory transfer and fixed-point landing time optimal guidance method for the lunar surface emergency rescue mission is proposed. Firstly, the whole process motion and dynamics model for the lunar surface emergency rescue with four stages are established. Then, in the initial orbit transfer phase, the Lambert algorithm based on "prediction + correction" is designed for the non spherical gravitational perturbation of the moon. In the powered descent phase, the Hamiltonian function is used to design a time suboptimal explicit guidance law that can be applied in orbit in real time. Finally, aiming at the multi-stage global time optimal guidance, the whole time process guidance law is obtained by establishing the allowable control set for each stage in the whole process. The simulation results show that compared with the piecewise optimal control method, the present method has better optimization effect and shorter whole process time. It is of great significance to the possible emergency rescue mission of manned lunar exploration in the future.

1 citations

Journal ArticleDOI
TL;DR: In this article, an independent method for determining the gravity acceleration vector is presented, implemented using information obtained from the gyro-inertial and radar instrumentation, which can result in a significant horizontal velocity at altitudes lower than 15 meters at instant when the landing legs contact the surface when data from the radar location system terminates.
Abstract: We know the spacecraft orientation before its touchdown on the Martian surface with an accuracy of 3–4°. The spacecraft control can result in a significant horizontal velocity at altitudes lower than 15 meters at the instant when the landing legs contact the surface when data from the radar location system terminates. An independent method for determining the gravity acceleration vector is presented in the paper. This method is implemented using information obtained from the gyro-inertial and radar instrumentation.

1 citations