The M19 was designed for long ranges,” says Igal Mevorach, Head of the Marketing & Business Development Administration at the TAMAM Division of IAI. “You can install it on large UAVs that operate at high altitudes, like the Heron and Heron-TP. The objective is to enable these vehicles to fly inside Israeli territory while photographing targets located outside this territory (stand-off intelligence). It features daytime and night HD quality video and still photography capabilities along with a laser pointer.”
As the camera is a video camera, the payload has to process each frame and send a video image in real time to the ground control station in the rear area. The full HD (1280×1024) night photography capability is made possible owing to the use of the cutting-edge Hercules thermal sensor by the Israeli Company SCD. The daytime channel is based on a civilian COTS camera that undergoes a ruggedizing process at IAI.
A lot of Pixels in Real Time
The M19 is a spherical payload weighing 75 kilograms and measuring 19” by 22”, which looks more like an ellipse. It has an aperture of 11” for the FLIR camera. The three sensors are mounted inside a gyro-stabilized platform with four gimbals – two external and two internal – that are completely isolated from the outside environment. Stabilization is accomplished by gyroscopes on two axes – elevation (pitch) and traverse (yaw). The roll axis is not stabilized. “If the UAV drops a wing, the surveillance operator will see the horizon diagonally. If the UAV is flying straight and level and you want to look down, you will be able to see along a 90-degree line under the UAV,” explains Mevorach.
Stabilization is accomplished by electro-mechanical means. A payload that includes a laser pointer requires physical stabilization of its line of sight in any situation, even when the UAV is maneuvering. This calls for very precise stabilization measured in microradians, namely – fractions of a degree. “In scenarios like combat operations in the Judea and Samaria district, the mission is relatively simple, but in scenarios where enemy SAM batteries and a hostile air force are involved, it is more complicated and you need a stand-off surveillance capability that would allow the UAV to fly in a relatively safe area,” says Mevorach. “With the M19 you position a Heron or Heron-TP UAV at a high altitude and look sideways to ranges of dozens of kilometers, out of your own national territory.”
Like the other payloads by IAI, the M19 is also intended to transmit real time images to a command center. Admittedly, it is not yet in operational use by IDF, but IAI sources say that trials are expected to begin soon using operational vehicles. “The UAV world is preparing to adopt the ability to receive HD transmissions, including the dissemination thereof to the end users. The challenge is with the data link, not just with the payload. Today, for UAVs that do not have a data link with HD bandwidth, we compress the image in the air, transmit and open the image on the ground. As the images are digital images, the process hardly involves any loss of image quality,” explains Mevorach. “Another method is to incorporate a data link for the HD band. In some places it already exists.”
Without a doubt, the introduction of HD quality day and night photographic capabilities, including a laser pointer and a wide bandwidth data link will contribute to the operational, publicity and legal efforts of the IDF. Mevorach says that with the M19 it will be possible to transmit high quality images from the UAV in real time – just like the broadcasts of a TV channel. Such an ability can make a significant contribution to the publicity efforts of the State of Israel as far as documenting terrorists firing out of populated areas is concerned, as well as in other situations.
Such an ability will also significantly enhance the incrimination capabilities of the IDF. It is no secret that these days, any fire attack by the IDF must be backed by photographic documentation so as to prove to the world that no uninvolved parties were attacked. In this context, the M19 payload can photograph the target before and after the attack while attaching a map reference to the images (just like the date attached to the images in home videos).
The M19 payload can also receive an accurate map reference from other IDF systems and commence documentation of that point automatically, as well as acquire an accurate map reference on its own and inject it into the system in the opposite direction. This capability is important, for example, in a scenario where an infantry team is located at a topographic point from which it is unable to see the target clearly. In such a situation, the team can “request” the UAV, by “pricking” the map reference on a hand-held computer screen, to provide an overhead view, including a map reference of the target.
“An infantryman can request a map reference from the UAV and receive images from overhead. It is a combination of a ‘geo’ function with the photographic capabilities of the payload,” says Mevorach. “Additionally, the payload can automatically track two targets simultaneously. Tracking is electronic. You position the crosshairs on the target and the system will track it automatically. This is accomplished through image processing.
“GPS is used to locate and position the payload. It relies on a satellite system and is accurate to within 10 meters. Additionally, the payload includes an inertial navigation system (INS) that measures the coordinates of the payload and its map reference, as well as measuring the spatial attitude angles of the payload. If the GPS fails, it will still be possible to use the INS. The dual existence of GPS and INS within the same payload provides redundancy and enables continuous tracking of targets even in an area saturated with jammers.”
Adaptable to Any Platform
Payload output is 1250 watts. Mevorach says that one should bear in mind the fact that this payload is installed on large UAVs with a suitable energy supply. Normally, these UAVs will carry both optical and Radar payloads. “Output savings are taken into consideration in the development of every payload. In addition to the fact that it is made of lightweight materials, the sensors are designed to save energy. The payload should be resistant to very high temperatures on the ground and to very low temperatures in the air, and its interior should maintain a permanent temperature. Traversing consumes energy as well. All of these constraints constitute a scientific challenge in the context of energetic efficiency,” explains Mevorach.
“At the end of the day, a military organization will place a UAV in the air if it is beneficial. There is an output budget and the optimum combination should be found. Our UAVs operate continuously for more than 24 hours, using payloads operating under full load. We managed to accomplish that through meticulous planning and miniaturization. For example, if a past surveillance system consisted of a spherical payload plus two different electronic boxes that contained power supply units and multiple electronics boards, today all of the electronics have been miniaturized into a single board installed inside the payload. This saves weight and energy.”
The M19 was designed to operate continuously for hundreds of hours. When an assembly needs to be replaced, its modular structure will enable the removal and replacement of the specific assembly. The faulty assembly will be shipped to the manufacturer’s laboratory for repair.
And what happens if the client has a fleet of UAVs of different types – will it be possible to have the new payload transferred from one type of UAV to another? “Today’s UAVs are built in advance with several bays for payloads. Specific preparatory adaptations should be made in advance in order to accommodate a specific payload. The bay where it will be installed on the UAV is prepared with a mechanical adaptor, an electrical adaptor and a connection to the UAV mission computer. A suitable software routine (driver) should be prepared as well. Every few years, we introduce a new generation of payloads which we design so that if you had purchased a UAV with the X payload, you would be able to change to the newer Y version fairly easily,” explains Mevorach.
“At the same time, if the client wishes to have the M19 installed on an aerial platform by a manufacturer other than IAI, this will be possible as well. It will require that we coordinate with the client the mechanical and electrical data of the bay where the payload is to be installed, including the communication protocol for the mission computer. We designed the new payload so it will be adaptable to any type of platform – UAVs, mission aircraft and helicopters.”
Source: Israel Defense