Jorge Ramirez

Requirements, Issues, and Challenges for Sense and Avoid in Unmanned Aircraft Systems

The sense and avoid capability is one of the greatest challenges that has to be addressed to safely integrate unmanned aircraft systems into civil and nonsegregated airspace. This paper gives a review of existing regulations, recommended practices, and standards in sense and avoid for unmanned aircraft systems. Gaps and issues are identified, as are the different factors that are likely to affect actual sense and avoid requirements. It is found that the operational environment (flight altitude, meteorological conditions, and class of airspace) plays an important role when determining the type of flying hazards that the unmanned aircraft system might encounter. In addition, the automation level and the data-link architecture of the unmanned aircraft system are key factors that will definitely determine the sense and avoid system requirements. Tactical unmanned aircraft, performing similar missions to general aviation, are found to be the most challenging systems from an sense and avoid point of view, and further research and development efforts are still needed before their seamless integration into nonsegregated airspace

A Proposal for Using UAS in Radio Navigation Aids Flight Inspection

The main objective of this paper is to contribute to the inherent necessity of the aerial transport system to guarantee the safety of its users in an efficient manner. This efficiency is required to accomplish the objective of transport people and goods with cost content enough to allow the access to this system at the biggest number of users. To improve this efficiency we propose a new paradigm in Flight Inspection Systems. This new paradigm separates the flight inspection platform in two separate segments, remaining in the air segment the strictly needed resources, the sensors, by mean of Unmanned Aerial Systems (UAS).

Remote Flight Inspection Using Unmanned Aircraft

Aircraft instrument navigation is based on radio signal technology provided by ground navigation aids (navaids). The International Civil Aviation Organization specifies the required navaids availability, quality, accuracy, and integrity for ground installations on service, including the flight inspection operations. Flight inspection is the task of validating the radio signal emitted by navaids. This paper presents the architecture of a novel system for flight inspection based on the use of unmanned aircraft. The proposed architecture is operated remotely and has flight inspection capabilities by using radio signal sensors. It also has a precise positioning system, based on global navigation satellite system, and uses a data link with low bandwidth, long range, and redundancy. Except for congested airports, the flight inspection is done in segregated airspace. These segregated airspace inspection flights could be a catapult for seriously considering unmanned aircraft benefits in civil services. Unmanned a...

Automatic Adjustment of Rigs to Extracted Skeletons

In the animation, the process of rigging a character is an elaborated and time consuming task. The rig is developed for a specific character, and it can not be reused in other meshes. In this paper we present a method to automatically adjust a human-like character rig to an arbitrary human-like 3D mesh, using a extracted skeleton obtained from the input mesh. Our method is based on the selection and extraction of feature points, to find an equivalence between an extracted skeleton and the animation rig.

Synthetic vision for Remotely Piloted Aircraft in non-segregated airspace

Synthetic Vision Systems (SVS) provide a computer-generated depiction of the environment according to aircraft flight path and attitude. In the case of Remotely-Piloted Aircraft (RPA), SVS improve dramatically operator situation awareness under reduced visibility conditions due to environment related issues and/or video data link degradation. Even though at their definition NextGen/SESAR frameworks were not thought to integrate RPA operations into non-segregated airspace, concepts such as flow corridors and technologies such as Traffic Information Service — Broadcast will ease their incorporation. This paper proposes and assesses new concepts applied to SVS in order to increase RPA operator situation awareness taking advantage of new data sources that may be available in the future NextGen/SESAR frameworks. Based on raw telemetry data and accessible terrain databases, a SVS is built. The integration of trajectory data and air traffic information is designed and implemented in order to determine its benefits.

Adjusting Animation Rigs to Human-Like 3D Models

In the animation process of a human-like 3D model, a skeleton must be specified to define the models surface deformation of its limbs. Nowadays the skeleton specification is hand made and very time consuming task. In this paper we propose a novel semi-automatic method for rigging a 3D model in an arbitrary pose using a skeleton defined in an animation datafile with no specific initial pose. First a skeleton is extracted from the voxelizated model, this skeleton is refined and transformed into a tree-data structure. Because the 3D model can be in an arbitrary pose, user interaction is required to select the five limbs correspondence (head, hands and feet), and finally a skeleton taken from an animation data file or a external source is adjusted to the geometric skeleton.

C3 in UAS as a Means for Secondary Navigation

Unmanned Air Systems (UAS) navigate using Global Navigation Satellite Systems (GNSS), but GNSS vulnerability precludes its use as the only means of navigation and requires a secondary means of navigation. A differentiating characteristic of UAS is their periodic communications with the ground station. This paper analyses the adequacy of employing UAS Command, Control and Communications (C3) as a secondary means of navigation. With no additional infrastructure, an Extended Kalman Filter (EKF) is used to process C3 messages and to obtain the positions of the UAS. Navigation accuracy and integrity are calculated in a scenario with three UAS. The obtained results meet the International Civil Aviation Organization (ICAO) Performance-Based Navigation (PBN) requirements.