Collision avoidance system

About: Collision avoidance system is a research topic. Over the lifetime, 1788 publications have been published within this topic receiving 23667 citations.

Cooperative Autonomous Collision Avoidance System for Unmanned Aerial Vehicle

Abstract: Autonomous collision avoidance system (ACAS) was defined and investigated in this paper to support UAVs integration to the national airspace system. This includes not only UAVs on-board system, but also the definition of requirements, collision avoidance structure, and the avoidance rules. This paper focuses on the cooperative avoidance, where UAVs (or any aircraft) involved avoid each other using rules previously agreed by involved parties. A novel algorithm of avoidance was developed, named as Selective Velocity Obstacle (SVO) method. Several simulations were conducted and show satisfying result on how well the algorithm work to avoid separation violations. In the end of the paper, using Monte Carlo simulation, violation probabilities were derived for three setups. These simulations shows the performance of the developed algorithm for cooperative ACAS, and suggesting the need to derive a new parameter, i.e., the minimum required turning rate of avoidance.

Design, integration and flight test of an autonomous ground collision avoidance system

Abstract: Currently, the majority of collision avoidance systems on fighter aircraft depend on the pilot taking action whenever a warning is issued by the manual system. Any future substantial reductions in mishap rates will require extending the collision avoidance technology to systems that not only warn the pilot but also take control and fly the aircraft out of danger before returning control to the pilot. An Automatic Ground Collision Avoidance System (Auto GCAS) will provide this extension of collision avoidance technology.

Adjustable object avoidance proximity threshold of a robotic vehicle based on presence of detected payload(s)

Abstract: Various embodiments include methods, devices, and robotic vehicles that adjust a proximity threshold implemented in a collision avoidance system based on whether a payload is being carried. Methods may include determining whether a payload is carried by the robotic vehicle, setting a proximity threshold for collision avoidance in response to determining that a payload is carried by the robotic vehicle, and controlling one or more motors of the robotic vehicle using the proximity threshold for collision avoidance. Some embodiments may include raising the proximity threshold when a payload is not being carried or decreasing proximity threshold when a payload is being carried. Some embodiments may include determining a classification of a payload and setting the proximity threshold based at least in part on the classification.

Reactive self collision avoidance with dynamic task prioritization for humanoid robots

Abstract: We propose a self collision avoidance system for humanoid robots designed for interacting with the real world. It protects not only the humanoid robots' hardware but also expands its working range while keeping smooth motions. It runs in real-time in order to handle unpredictable reactive tasks such as reaching to moving targets tracked by vision during dynamic motions like e.g. biped walking. The collision avoidance is composed of two important elements. The first element is reactive self collision avoidance which controls critical segments in only one direction — as opposed to other methods which use 3D position control. The virtual force for the collision avoidance is applied to this direction and therefore the system has more redundant degrees of freedom which can be used for other criteria. The other second element is a dynamic task prioritization scheme which blends the priority between target reaching and collision avoidance motions in a simple way. The priority between the two controllers is changed depending on current risk. We test the algorithm on our humanoid robot ASIMO and works while the robot is standing and walking. Reaching motions from the front to the side of the body without the arm colliding with the body are possible. Even if the target is inside the body, the arm stops at the closest point to the target outside the body. The collision avoidance is working as one module of a hierarchical reactive system and realizes reactive motions. The proposed scheme can be used for other applications: We also apply it to realizing a body schema and occlusion avoidance.

Surveillance system for collision avoidance of aircrafts using radar beacon

Abstract: A collision avoidance system using on-board B-CAS equipment having an object to minimize interference with the ground SSR stations and to effect precise tracking or distance-altitude measurement when necessary. Normally passive surveillance is made to detect the presence of other aircraft in the B-CAS range. Active surveillance is added when required. In the active surveillance mode, initiated on locating an intruder aircraft, the power and interrogation signal are varied when the intruder aircraft becomes a threat aircraft to minimize interference with the ground SSR stations and aircraft outside the threat zone while maintaining accuracy of detection and tracking of the threat aircraft at a high level.