Patent Application
20240194084
This application is based upon and claims priority to Turkish Patent Application No. 2022/019173, filed on Dec. 13, 2022, the entire contents of which are incorporated herein by reference.
The invention relates to a collision avoidance system and method for detecting obstacles or terrain likely to be encountered by fixed wing or rotary wing platform aircraft in bad weather conditions or at low altitude, and for alerting the user in advance, with a variable protection zone that reduces unnecessary alerts.
Nowadays, it is observed that there are obstacles and terrain (elevations such as mountains, hills and power lines etc.) that will affect the safe flight of aircraft flying at a certain height. There are alerting systems that will notify the pilot against possible collisions with these obstacles and terrain that threaten the safe flight of aircraft. These alerting systems are divided into two as passive systems and active systems. In active systems, the obstacles or terrain in front of the aircraft are detected by means of electromagnetic, radar or laser, but these systems are generally not preferred due to their heavy weight and the fact that the weight of the aircraft is a factor affecting the flight performance. Passive systems include geo-location-based prevention systems and physical prevention systems (cable cutter truss). Especially in geo-location-based interceptor systems, databases containing terrain height data and obstacles are used. These systems provide pre-collision alerts to the pilot by using the aircraft's position, altitude, track angle and speed data. Geo-location-based interceptor systems in the known state of the art alert according to the position of the aircraft using obstacle and terrain databases and GPS, but cannot generate an alert according to the orientation of the aircraft. This causes unnecessary alerts to be given to obstacles or terrain that do not pose a threat during turning maneuvers and the problem of not being able to give alerts to obstacles or terrain that are likely to collide due to orientation. This problem increases the workload of the pilots, reduces the confidence to the system and causes the pilot to inhibit the system in systems that generate audible alerts.
In the document U.S. Pat. No. 9,196,168, which is in the prior art, an obstacle and terrain alerting system for helicopters is mentioned. In the said patent document, it is explained that radar systems are used to detect obstacles and terrain at a certain distance. In the said invention, the system alerts the user in objects that are not likely to get in front of the aircraft according to the direction of movement of the aircraft, but enter the radar. This situation causes the aircraft to generate alerts to obstacles or terrain that are not likely to be encountered. In addition, it cannot give an alert according to the orientation of the aircraft, which causes unnecessary alerts or the problem of not alerting the obstacles or terrain that are likely to collide due to the orientation.
The purpose of the invention is to provide a collision avoidance system and method that better detects obstacles or terrain that pose a threat to the aircraft and does not alert against obstacles or terrain that do not pose a risk of collision according to the direction of movement of the aircraft. Another purpose of the invention is to provide a collision avoidance system and method for detecting possible obstacles or terrain relative to the rotation of the aircraft.
A collision avoidance system according to the purpose of the invention as defined in the first claim and the dependent claims of the present invention, for detecting obstacles or terrain likely to be encountered by fixed wing or rotary wing platform aircraft in bad weather conditions or at low altitude, and for alerting the user in advance. The collision avoidance system includes a sensor module to detect the position, track angle, ground speed and altitude of the aircraft. There is a memory module with terrain and obstacle databases. This database consists of terrain elevation data (DTED—Digital Terrain Elevation Data) and object data including geographical locations of objects such as power lines, television antenna masts, wind turbines, water tanks, etc. Using the data from the sensor module, a control unit is adapted to determine the path/distance to be travelled by the aircraft as a corridor. The created corridor determines the points that the aircraft can reach according to its linear progress. In case there is an obstacle or terrain on the corridor of the aircraft, in other words, if one of the corridor points that the aircraft can reach after a predetermined time intersects with an obstacle or terrain, the control unit includes an adapted alerting system to alert the user.
A collision avoidance method as defined in the first claim of the present invention and the dependent claims, wherein the position, sea level altitude, track angle and ground speed values of the aircraft are received from the sensor module. With the values received by the control unit from the sensor module, the corridor that the aircraft will reach after a certain period of time is determined. The obstacles and terrain data within the corridor are read from the memory module. It is evaluated whether the determined corridor intersects with any obstacle/terrain or not. If an obstacle or terrain is encountered, the control unit sends an alert to the alerting system so that the user is aware of the obstacle or terrain. If the point that the aircraft will reach after a certain period of time does not intersect with any obstacle or terrain and an alert is currently active, a separate command is sent to the audible alerting system to remove the alert. The current data received from the sensor module is read from the sensor module in certain periods and the same calculations are made and continuous protection is provided.
A collision avoidance system for achieving the object of the present invention is shown in the accompanying figures;
The parts in the figures are individually numbered and the equivalents of these numbers are given below.
A collision avoidance system (1) according to the invention, for detecting obstacles and terrain likely to be encountered by fixed-wing or rotary-wing platform aircraft (H) in bad weather or at low altitude, and for alerting the user in advance;
The inventive collision avoidance system (1) is designed to detect and warn the user in advance of obstacles and terrain likely to be encountered by fixed wing or rotary wing platform aircraft (H) in bad weather conditions or at low altitude. The collision avoidance system (1) includes a sensor module (2) that can detect the position, track angle, ground speed and sea level altitude of the aircraft (H). The system also includes a memory module (3) with obstacle and terrain databases. These databases contain terrain elevation data (DTED—Digital Terrain Elevation Data), geographical positions of objects such as power lines, television antenna masts, wind turbines, water tanks, etc. From the sensor module (2), the position of the aircraft (H), sea level altitude, ground speed and track angle are sent to the control unit (4). Using the received values, the control unit (4) determines the path/distance to be travelled by the aircraft (H), e.g. after a maximum of 20 s, as a corridor (K). The control unit (4) processes the generated corridor (K) with the obstacle and terrain database received from the memory module (3). The generated corridor (K) determines the points that the aircraft (H) can reach according to its linear progress. If there is an obstacle or terrain on the corridor (K) of the aircraft (H) according to the obstacle and terrain databases, in other words, if the corridor (K), which the aircraft (H) can reach after a predetermined time, encounters an obstacle or terrain according to the obstacle and terrain database, the control unit (4) generates visual and audible alerts to inform the user. Visual alerts are displayed to the user on the display device (5). Audible alerts are also transmitted to the user via the audible alerting system (6). The collision avoidance system (1) according to the invention better detects obstacles and terrain that pose a threat to the aircraft (H) and does not alert against obstacles and terrain that do not pose a risk of collision according to the track angle direction (i) of the aircraft (H). Furthermore, the inventive subject matter enables the aircraft (H) to detect possible obstacles and terrain according to the turn of the aircraft (H).
In more detail, the control unit (4) creates a corridor (K) with width, length, and depth in order to predict the path/distance to be travelled by the aircraft (H) after a predetermined period of time, e.g. after a maximum of 20 seconds. In order to determine the length of the corridor (K) in meters, the following formula is applied by the control unit (4).
Corridor (K) length (m)=Aircraft (H) ground speed (m/s)×20 s
Corridor (K) width (m)=Aircraft (H) ground speed (m/s)×20 s
Based on the aircraft (H) data received from the sensor module (2), the control unit (4) creates a volumetric corridor (K) with width, length and depth values. The control unit (4) creates the corridor (K) with the aircraft (H) positioned at the head. This positioning is shown in
During the turn of the aircraft (H), in other words, when the track angle of the aircraft (H) changes, the linearly determined corridor (K) covers areas that are not likely to be encountered by the aircraft (H) and therefore unnecessary alerts may be generated. In order to prevent unnecessary alerts, during the turn of the aircraft (H), in other words, when the track angle of the aircraft (H) changes, the control unit (4), using the data received from the sensor module (2), expands the corridor (K) area by a certain angle (α) according to the track angle change of the aircraft (H) and the track angle direction (i). A triangle is formed according to the track angle direction (i) from the angle (α) value obtained by multiplying the rotation speed (degrees/second) of the aircraft (H) by a predetermined constant and the width and length values generated by the control unit (4). The angle (α) of this triangle is shown on
In a preferred embodiment of the invention, a display device (5) is adapted to display alerts generated by the control unit (4). The display device (5) shows the instantaneous position of the aircraft (H) and the corridor (K) specified by the control unit (4). By means of the display device (5), the user can also see the position of the obstacles or terrain and thus determine which direction to steer the aircraft (H) in dark and foggy weather conditions.
In a preferred embodiment of the invention, the audible alerting system (6) comprises a sound system and provides an audible alert to the user when an alert is generated.
The reference numerals in the flow diagram shown in
A collision avoidance method adapted for the operation of a collision avoidance system (1) according to the invention, characterized in that includes the following method steps;
In a collision avoidance method adapted for operation in a collision avoidance system (1) of the invention, the position, sea level altitude, track angle and speed relative to the ground of the aircraft (H) are received from the sensor module (2) (101). Using the values received by the control unit (4), the corridor (K) that the aircraft (H) will reach after a certain time is determined (102). The difference between the track angle and the previous track angle and then the rotation speed of the aircraft (H) are determined by using this difference (103). Then, the control unit (4) expands the corridor (K) that the aircraft (H) will reach after a certain period of time by a certain angle (α) according to the track angle, rotation speed and track angle direction (i) of the aircraft (H), and removes the non-threatening regions from the corridor (K) and the final corridor (K) is determined (104). The obstacles and terrain within the corridor (K) determined by the control unit (4) are read from the memory module (3) (105). The control unit (4) evaluates whether the determined corridor (K) intersects any obstacle or terrain read from the memory module (3) (106). If the corridor (K) intersects an obstacle or terrain, the control unit (4) sends an alert to the audible alerting system (6) (107). If there is no intersection and an alert is currently active, it sends a command to the audible alerting system (6) to remove the existing alerts and the alert is removed from the audible alerting system (6) (108). After the control unit (4) has completed all the operations, it proceeds to step 101 to read the current data from the sensor module (2) and perform the same operations again, thus providing continuous protection. The inventive collision avoidance method provides a better detection of obstacles or terrain that pose a threat to the aircraft (H) and does not alert against obstacles or terrain that do not pose a risk of collision with respect to the track angle direction (i) of the aircraft (H). Furthermore, the invention enables the aircraft (H) to detect possible obstacles or terrain according to its rotation.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022/019173 | Dec 2022 | TR | national |
