Promising combat UAVs from the company "IMPULS 82": without diversity of species there will be no natural selection

30
Promising combat UAVs from the company "IMPULS 82": without diversity of species there will be no natural selection


Factors of evolutionary selection


It has probably become a platitude to say that the Russian special military operation (SMO) in Ukraine has largely become a war of unmanned aerial vehicles (UAVs).



Again, it is a secret to few that at first the Armed Forces of Ukraine (AFU) were ahead of us both in the quantity and quality of the UAVs used. And it is not only about the help of Western countries, although it is of great importance, but also about the lack of competitive air forces (AF), a shortage of artillery shells and cruise missiles The Ukrainian Armed Forces have placed their bets on UAVs.

As a result, they took a number of organizational measures, which resulted in intensive and extensive development of areas for the creation and use of UAVs. For example, Ukraine has already created a force of unmanned systems (UWS), but we do not have a similar branch of the armed forces yet.

At the same time, the Ukrainian SBS are just starting their activities, and their contribution to future Ukrainian victories or defeats is not yet clear, but Ukrainian UAVs have been causing us problems for a long time, so what is Ukraine's advantage?


Coat of arms of the Ukrainian SBS

It can be assumed that one of the most important factors was the permission to engage in UAVs for everyone who is ready to do so – small enterprises and design bureaus, pasta factories and manufacturers of plumbing, it does not matter whether they employ 2 people or 10000 people, as long as they produce products.

The second factor was the provision of financing and timely purchase of manufactured products for their subsequent use by the Armed Forces of Ukraine.

And finally, the third factor is the presence of deep feedback loops that allow one to evaluate the effectiveness of a particular model, which allowed the Armed Forces of Ukraine to intensify development and increase purchases of those UAVs that performed well on the battlefield, and this allowed developers and manufacturers to quickly eliminate shortcomings and increase the effectiveness of their products.

It is important to understand that the topic of UAVs is very “live”, since combat UAVs are in constant confrontation with electronic warfare systems (EW). This means that what was developed before or at the very beginning of the SVO may simply no longer be operational, since the communication channels and video signal transmission of such UAVs are easily “choked” by the also evolved electronic warfare systems.

In Russia, the situation is twofold: on the one hand, there seem to be no particular obstacles to the development of UAV technology, but the financing of small businesses is in question, as are the supply and distribution channels for their products.

Often, those who were able to get under some investment project or “under the wing” of a large volunteer movement receive funding from the state or from private individuals, while for others it can be quite difficult to break into the SVO zone.

We have previously considered one of the domestic enterprises, manufacturers of aircraft-type kamikaze UAVs in the material "Hello" from KB "Oko" - it is possible that the Russian UAV storm begins today.

Today we will talk about the aircraft-type UAV developed and manufactured by the company "IMPULS 82" from the city of Simferopol.

By the way, this company is also a manufacturer of electronic warfare systems that can be used on both ground-based equipment and UAVs, which potentially allows for a very interesting “symbiosis”.

About Us


As a legal entity, the company "IMPULS 82" was founded quite recently and previously represented a team of like-minded people engaged in the development and small-scale production of aircraft-type UAVs within the framework of an aircraft modeling club, starting in 2015.

At that time, the main areas of application of UAVs were considered to be various civilian sectors of the national economy, such as mapping, solving geodetic problems, use in the interests of the Ministry of Emergency Situations (MES) of Russia, and others.


Between 2015 and 2017, 5 aircraft-type UAV prototypes were developed and assembled, manufactured using a normal aerodynamic configuration and a flying wing configuration. These UAVs underwent flight tests and participated in demonstration performances in Russia and Kazakhstan, where they received high marks for their design and flight characteristics.

Since 2017, the design documentation for UAV prototypes has been digitized for their subsequent production using modern composite materials and CNC machines. The UAV's filling has also changed, new control systems have been developed on a modern component base, and modern video surveillance equipment has been installed.


In parallel, in 2018–2021, specialists from the future company “IMPULS 82” were involved in the development of UAVs by one of the largest Russian companies in this area, whose name, unfortunately, cannot be disclosed due to current confidentiality agreements.

Since February 2022, when the Second World War began in Ukraine, the team of the future company "IMPULS 82" began developing a new direction for itself - electronic warfare equipment, which resulted in the development of a series of "TUMAN" products designed to counter enemy UAVs.

The TUMAN electronic warfare modules can be used in a stationary version or applied for installation on combat vehicles and civilian transport vehicles; perhaps we will return to this area of ​​activity of the IMPULSE 82 company.


Electronic warfare unit "TUMAN"

In the context of this article, an interesting point is the possibility of integrating the TUMAN electronic warfare system onto UAVs, but more on that below.

Thus, specialists from the company “IMPULS 82” have developed three models of aircraft-type UAVs, on the basis of which it is possible to create modifications.

"FALCON", "SKAT" and "ADEBRA"


UAV "FALCON" is made according to a normal aerodynamic scheme and, depending on the modification, can have a wingspan of three to five meters and be equipped with two- or four-stroke internal combustion engines running on 92-octane automobile gasoline. The payload, depending on the modification, is from 1,5 to 5 kilograms.


UAV "FALCON"

The test samples achieved a maximum flight altitude of 4000 meters. At a cruising flight speed of 120 kilometers per hour, the flight time is 9 hours according to coordinates, i.e. the flight range of the SOKOL UAV exceeds 1000 kilometers. The range of action with remote control and receiving an image from a video camera is up to 50 kilometers.

Next model is – UAV "SKAT", made according to the "flying wing" scheme, with a wingspan of 3,2 meters, with an electric motor powered by batteries. The full takeoff weight of the UAV "SKAT" is 11 kilograms, the payload is 2,5 kilograms.

At a maximum flight altitude of 3000 meters at a speed of 95 kilometers per hour, the flight time was 5 hours, that is, the flight range of the SKAT UAV is about 500 kilometers, the takeoff of the SKAT UAV is carried out from a catapult, landing by parachute.


UAV "SKAT"

During test flights, a camera and a high-speed shooting camera (up to 5000 shots per minute) were installed on the SKAT UAV for the purpose of performing cartographic and geodetic tasks, reconnaissance, or observation of terrain and objects.

The flying wing aerodynamic configuration used in the SKAT UAV should potentially have a significantly lower radar signature compared to aircraft with a traditional configuration, made using a normal aerodynamic configuration or a canard configuration.

In 2023 it was developed and tested UAV "ADEBRA", which is essentially a seaplane UAV (Has anyone ever seen similar models, at least domestic ones?), capable of taking off from and landing on water – during tests, takeoff and landing were carried out in sea conditions of 1 point.


UAV "ADEBRA"

The takeoff weight of the UAV "ADEBRA" is 22 kilograms, the payload is up to 4,5 kilograms. At a maximum flight altitude of 5000 meters at a speed of 250 kilometers per hour, the flight time is 2,5 hours.

The patrol time on the water surface with periodic takeoffs and landings can reach 24 hours.

Currently, a prototype of the ADEBRA UAV with an electric engine and battery power has been tested. Other options for implementing the ADEBRA UAV, larger in size, with a gasoline engine or a hybrid system including a small diesel generator and an electric motor, are also being considered.

All the UAV models considered above are equipped with modern interference-resistant control systems, and can additionally be equipped with the “TUMAN” electronic warfare protection system, also manufactured by the “IMPULSE 82” company, designed to suppress video surveillance signals and FPV control channels.drones the enemy, which he is now using to hunt our long-range UAVs.

The main tasks for which it is planned to use the SOKOL, SKAT and ADEBRA UAVs, taking into account current realities, are reconnaissance, the use of electronic warfare systems, and in the future, the solution of strike missions as kamikaze UAVs, attacking either at specified coordinates or at the operator’s commands.

The possibility of equipping some UAV models with relay equipment and FPV attack drones to increase the range of the latter, i.e. turning an aircraft-type UAV into an “aircraft mother”, is also being considered.

Separately, it is necessary to mention the possibility of integrating a small-sized sonar, submerged on a cable to a depth of 70 meters, intended for monitoring water areas, onto the ADEBRA UAV, which is being developed.

Conclusions


Currently, the main focus of the IMPULSE-82 company is the production and delivery of electronic warfare equipment of the TUMAN family to the air defense zone – this focus required less initial financial resources to deploy production.

But even in the case of electronic warfare systems, there are financing problems, since our own funds only allow us to produce a small batch of electronic warfare systems; after they are sold, the proceeds are used to manufacture a new batch, and then the cycle repeats – production volumes increase very slowly.

Given the current financial situation, as well as the fact that electronics are largely purchased from China, there are risks of not only an increase in the production volumes of electronic warfare systems, but also a decrease.

With UAVs, things are even more complicated – this area requires even more financial resources to start serial production, while for now we can limit ourselves to only prototypes.

In this regard, the company "IMPULS 82" is interested in working with any partners who can help with financing, no matter whether they are government structures - holdings or corporations, or volunteers, individuals or commercial companies.

Both existing products and products modified according to the customer's technical specifications can be supplied. It is also possible to expand production of products at the partners' facilities.

As we already said at the beginning of the article, in the UAV and EW segments, the diversity of types – models, concepts, technical solutions – is of great importance. It is the diversity of types that allows the enemy to often be one step ahead of us – by conducting an evolutionary selection of the best samples from the many available.

The issue of diversity can only be resolved by involving many independent private contractors in the development and production of UAVs and electronic warfare systems, and the Russian Armed Forces also need to step up their work in this direction.

Let's hope that we will still see how the SOKOL, SKAT and ADEBRA UAVs will perform targeted tasks of the Russian Armed Forces, as well as be used in civilian unmanned aerial vehicles. aviation.
30 comments
Information
Dear reader, to leave comments on the publication, you must sign in.
  1. +3
    30 November 2024 04: 35
    It is worth paying attention to the Australian development of a kamikaze drone made of cardboard soaked in paraffin. This will allow for rapid mass production, and the price will be acceptable. In addition, when unfolded, it is a sheet of cardboard, an engine, a charger, and a control device with a camera.
    1. +3
      30 November 2024 06: 39
      Quote: Vladimir_Borisovich
      a kamikaze drone made of cardboard

      THIS. MAKES NO SENSE! the cost of the fuselage in the final cost of the product is a pitiful percentage, the main cost is electronics and optics, and their cost cannot be reduced without losing quality!
    2. 0
      1 December 2024 19: 29
      The cost of the device will be very small, and our officials will demand large kickbacks. That is why we have such a problem with UAVs - they do not shoot, as in China, for bribes.
  2. +3
    30 November 2024 04: 39
    For some reason I remembered my childhood: aviation modeling clubs in the Pioneer Houses. Who could have thought then...
    1. -1
      30 November 2024 13: 56
      And what now? Only in clubs grown-up uncles with money or financing. And this is the Modern Army? And where is the concept of Modern Combat and the concept of using UAVs in it. The country of unlearned lessons! There is no concept of SB, but the concept of using UAVs in it seems to have emerged?! This does not happen in a well-oiled and well-thought-out mechanism. A rider gallops without a horse, congratulations to the brilliant Headquarters of the Armed Forces of Russia! When will it tell us about Modern Warfare and how to fight in it without nuclear weapons? Incompetent and stupid generals always do this. Ask any general or colonel how he understands modern warfare, and he will immediately ... fall into a stupor. Ask, try to ask anyone ...
  3. +5
    30 November 2024 05: 11
    "...As a result, they took a number of organizational measures, the consequence of which was the intensive and extensive development of areas for the creation and use of UAVs. For example, in Ukraine, unmanned systems forces (USF) have already been created, while we do not yet have a similar branch of the armed forces..."[B] [/ b]

    Even during the Karabakh war (At the hour of triumph of "bayraktars" and other UAVs... Many years ago. (NOW!)) many domestic, constantly and annoyingly - getting in the way (kopecks) of "big" military officials..., - couch potatoes and "jackasses", including me..., expressed some "modest" and "naively unprofessional" - considerations..., and made comments about the urgent need not only to acquire, create and master the corresponding technical means - a completely new..., and very effective (As Time and Military Practice have shown...) type of weapons..., but also to create a completely new type of the Armed Forces (branch of troops.) - UAV-aviation units... With their own command, supplies, etc., etc.

    However, judging by the recent "sensational" speeches of the Supreme Commander-in-Chief at the recent summit..., concrete and real steps in this direction (the creation of a separate type (branch) of troops... - UAV-aircraft units, as our enemies HAVE ALREADY DONE LONG AGO (!!!)), are only now being planned (or are they planning to?!!..)...
    After, in fact, already a whole "era" in the development of this new and very dangerous type of weapon!..

    What is this? - The dominance of enemy agents and traitors, somewhere in the very top of our highest military officials of the Armed Forces and the Defense Industry?..
    Exceptionally weak and feeble work of the Russian counterintelligence?.. Or traitors in the Russian counterintelligence?..
    Or is it the banal stupidity of some two-legged demons with big stars on their shoulder straps?..
    Or is it all taken together?..

    A well-known legend claims that the work on the Nuclear Project in the USSR really began to boil after an appeal to Stalin personally (a letter was sent) from a certain unknown Front "lieutenant", a PATRIOT..., who pointed out the sudden cessation of scientific publications on Nuclear topics by Our allies (friends and partners) - future Geopolitical enemies...
    Which clearly indicated that the future potential enemy had achieved certain and dangerous successes for the USSR in these studies and developments...

    That Supreme One reacted instantly, having properly stepped on the genitals of some overfed and relaxed military-scientific bastard (most likely, some were sent to prison, or propped up with their asses against the wall!), AND WORK IN THIS DIRECTION INSTANTLY AND POWERFULLY BEGAN TO BOIL...

    So maybe the current supreme leader should, casting aside his disgust, occupy himself with the genitals of various corrupt, stupid, talentless, lazy, inert military and defense bureaucratic "brotherhood"?..

    I am not inclined to exaggerate the capabilities of UAVs in modern warfare... But the danger of this insidious and ruthless type of weapon should not be diminished...

    Isn't this what the very same "wasps of the apocalypse" are?..
    1. +1
      30 November 2024 06: 21
      I have known a couple of enthusiasts since 2014 who fought in Donbass during the Russian Spring TEN YEARS AGO.
      Our Ministry of Defense, as always, is at the height of inertia of thinking. Both Putin and Belousov raised the topic of drones this fall. Perhaps a kick from above will give this direction some acceleration, but this raises doubts. Once again, we have manual control, and the enemy has folk art.
      I remember Stalin's OSOVIAKHIM and the cry "Everyone to the plane", aircraft modeling, gliding, and parachuting clubs.
      By the way, it looks like Maxim Klimov is working on the UAV topic.
      1. +2
        30 November 2024 18: 55
        Our Ministry of Defense is now being criticized by everyone and often for good reason. If you look at the situation with UAVs from a slightly different angle, the following will become clear. The fuselage is not a problem, it can be developed and made. It gets worse. What to do with the engine. All my gasoline-powered equipment has imported engines, and even the motorcycle engine has German roots. Ambush request How are things with video cameras? To put it mildly, not very good. And what about other components? We made Orlan, or rather assembled it from what we bought from "partners". It is impossible to adopt such equipment, as time has shown.
    2. +1
      30 November 2024 06: 26
      Quote: Evil_Soviet_Zionist
      Even during the Karabakh war (At the hour of triumph of the "Bayraktars" and other UAVs...
      The first warning bell that we should pay close attention to drones rang out in Syria. Then in Libya. And during the Karabakh war, all the generals, braided in gold braid, began to scratch their heads, which were not very full of brains. But they were still scratching their heads.
      So maybe the current supreme leader should, casting aside his disgust, occupy himself with the genitals of various corrupt, stupid, talentless, lazy, inert military and defense bureaucratic "brotherhood"?..
      The current one? For that you need the level of Comrade Stalin wink
      1. +1
        30 November 2024 06: 38
        Current one? For this you need the level of Comrade Stalin

        ...ALAS!..
      2. +3
        30 November 2024 08: 35
        Quote: Dutchman Michel
        The first warning sign that we need to pay close attention to drones came from Syria.

        No way! The "first bell" rang in Lebanon in 1982, when the Israelis, using reconnaissance UAVs equipped with explosives, smashed the Syrian air defense! By the way, Soviet military advisers paid attention to this fact and reported to the "Kremlin" ... but there was no proper reaction!
        1. -1
          30 November 2024 08: 51
          Quote: Nikolaevich I
          The "first bell" rang in Lebanon in 1982, when the Israelis, using reconnaissance UAVs equipped with explosives, destroyed the Syrian air defenses.
          Well, it's not exactly a drone in the classical sense. Just like our Tu-141 "Strizh"
          1. +1
            30 November 2024 10: 43
            Quote: Dutchman Michel
            Well, it's not exactly a drone in the classical sense.

            belay belay belay What is a "drone in the classical sense"? what Explain, please! "Honey - it's either there or it's not!" (wisdom of the breeders of the "Winnie the Pooh" bear subspecies)...
            1. 0
              30 November 2024 10: 46
              Quote: Nikolaevich I
              What is a "drone in the classical sense"?
              It's like trying to explain how many angels you can fit on the tip of a pin. wink
              1. 0
                30 November 2024 11: 00
                I understand you... I sympathize with you... it must be hard when you feel like you have half a liter, but you can’t say (pronounce) it! wink Or are you just like that...?
                1. -1
                  30 November 2024 11: 03
                  Or are you just like that...?
                  With you, just like that. And it's a pity about the lost time
                  1. +1
                    30 November 2024 11: 28
                    Quote: Dutchman Michel
                    It's a pity about the wasted time

                    Me too....
    3. +2
      30 November 2024 09: 31
      after an appeal to Stalin personally (a letter was sent) by a certain unknown Front "lieutenant", a PATRIOT..., - who pointed out the sudden cessation of scientific publications on Nuclear topics by Our allies (friends and partners) - future Geopolitical enemies...
      Letters from Flerov from 41 and 42. In the photo is a cover letter from Kurchatov to Makhnev from 1946.
      1. 0
        30 November 2024 13: 06
        ...I am very GRATEFUL to you for the valuable information!..)))))))))..
    4. 0
      30 November 2024 14: 48
      Even during the Karabakh war (At the hour of triumph of the "Bayraktars" and other UAVs... Many years ago.

      We started actively talking about drones right after 2008.
      https://lenta.ru/news/2009/08/05/drones/
      Here, already in 2009, according to the Air Force commander-in-chief, all sorts of different programs began. But everything was stolen, the son-in-law of a member of the Duma Defense Committee, for example, built himself a jewelry boutique in Cyprus with the money for the Altair
      https://www.kp.ru/daily/26964/4019281/
      With drones, it’s like with import substitution - we talked, allocated money, forgot, saw that there was no money or import substitution, pretended that nothing had happened - returned to the beginning of the path with the allocation of money to all sorts of crooks.
  4. +1
    30 November 2024 07: 26
    Surprisingly, we still don't see any drones to defend against drones.
    After all, it is enough to look at the history of aviation development in the First and Second World Wars and it is obvious that reconnaissance aircraft appeared first. Then they started dropping bombs from aircraft. Then fighters appeared to counter these bombers. And fighter aviation played a huge role. Can you imagine if it had not existed?
    The drone story will repeat all this.
    Why doesn't anyone start making a drone in the form of a 1:5 model, for example, LA-7, to clear the skies of enemy drones. Good optics, a radiation source identifier and a couple of canisters and the drone problem will be greatly reduced. If such a fighter operates in a square over its territory, then even a friend-or-foe identifier is not required. By definition, all drones over its territory are enemy.
    1. +1
      30 November 2024 13: 08
      We just didn't come across them: versions with a throwing net and high-speed interceptors were presented by our developers. Net throwers are used no less than GOA. Both ours and the Ukrainians use FPV against medium drones.
      1. +1
        30 November 2024 15: 06
        These are nets for now. Against large, non-maneuverable drones. But drone air battles are not far off. There, both maneuverability and range will matter.
    2. -1
      1 December 2024 03: 55
      Why doesn't anyone start making a drone in the form of a 1:5 model, for example, the LA-7, to clear the skies of enemy drones?

      Once the Americans start, everyone will start.
      Working ahead is not our method.
      There are few logical arguments. In order for someone to start working in a new direction in the swamp of the Ministry of Defense, some kind of catastrophe needs to happen. And judging by everything, tens of thousands of dead soldiers and thousands of burned tanks BMP BTR are not enough. This is not enough.
      When the roasted rooster pecks your ass to the bone, then they will hold a meeting on this topic. And they will start thinking.
  5. Eug
    +1
    30 November 2024 09: 50
    It is necessary to create a COMBAT SYSTEM, and under it - a WEAPONS SYSTEM, part of which will be UAVs. And already based on the views on the battle of the future and its varieties - to create UAVs as a weapons subsystem. Maximum modularity and flexibility. And also - as for me, the successes (let's be honest) of Ukraine in the use and development of UAVs are explained not least by the fact that this topic is led not by the Ministry of Defense, but by the Ministry of Digitalization, which is much more flexible and receptive to promising innovations...
  6. +1
    30 November 2024 13: 14
    Coat of arms of the Ukrainian SBS

    Looks like a fascist eagle.
    Well, slaves want to be like their master.
    So to speak, Stockholm syndrome (it’s not about slaves, but the essence is the same). lol
    1. 0
      30 November 2024 13: 23
      Quote: K-50
      Coat of arms of the Ukrainian SBS

      Looks like a fascist eagle.
      Well, slaves want to be like their master.
      So to speak, Stockholm syndrome (it’s not about slaves, but the essence is the same). lol


      Yes, I even wanted to place it next to it for comparison...
  7. 0
    30 November 2024 14: 51
    Quote: Evil_Soviet_Zionist
    "...As a result, they took a number of organizational measures, the consequence of which was the intensive and extensive development of areas for the creation and use of UAVs. For example, in Ukraine, unmanned systems forces (USF) have already been created, while we do not yet have a similar branch of the armed forces..."[B] [/ b]

    Even during the Karabakh war (At the hour of triumph of "bayraktars" and other UAVs... Many years ago. (NOW!)) many domestic, constantly and annoyingly - getting in the way (kopecks) of "big" military officials..., - couch potatoes and "jackasses", including me..., expressed some "modest" and "naively unprofessional" - considerations..., and made comments about the urgent need not only to acquire, create and master the corresponding technical means - a completely new..., and very effective (As Time and Military Practice have shown...) type of weapons..., but also to create a completely new type of the Armed Forces (branch of troops.) - UAV-aviation units... With their own command, supplies, etc., etc.

    However, judging by the recent "sensational" speeches of the Supreme Commander-in-Chief at the recent summit..., concrete and real steps in this direction (the creation of a separate type (branch) of troops... - UAV-aircraft units, as our enemies HAVE ALREADY DONE LONG AGO (!!!)), are only now being planned (or are they planning to?!!..)...
    After, in fact, already a whole "era" in the development of this new and very dangerous type of weapon!..

    What is this? - The dominance of enemy agents and traitors, somewhere in the very top of our highest military officials of the Armed Forces and the Defense Industry?..
    Exceptionally weak and feeble work of the Russian counterintelligence?.. Or traitors in the Russian counterintelligence?..
    Or is it the banal stupidity of some two-legged demons with big stars on their shoulder straps?..
    Or is it all taken together?..

    A well-known legend claims that the work on the Nuclear Project in the USSR really began to boil after an appeal to Stalin personally (a letter was sent) from a certain unknown Front "lieutenant", a PATRIOT..., who pointed out the sudden cessation of scientific publications on Nuclear topics by Our allies (friends and partners) - future Geopolitical enemies...
    Which clearly indicated that the future potential enemy had achieved certain and dangerous successes for the USSR in these studies and developments...

    That Supreme One reacted instantly, having properly stepped on the genitals of some overfed and relaxed military-scientific bastard (most likely, some were sent to prison, or propped up with their asses against the wall!), AND WORK IN THIS DIRECTION INSTANTLY AND POWERFULLY BEGAN TO BOIL...

    So maybe the current supreme leader should, casting aside his disgust, occupy himself with the genitals of various corrupt, stupid, talentless, lazy, inert military and defense bureaucratic "brotherhood"?..

    I am not inclined to exaggerate the capabilities of UAVs in modern warfare... But the danger of this insidious and ruthless type of weapon should not be diminished..."
    Isn't this what the very same "wasps of the apocalypse" are?..


    A legend is a legend. A front-line soldier who received Western publications on nuclear topics directly to the front!
    Open Wiki and read "Work in the field of the atomic nucleus in the USSR in the 1930s-1940s", "Creation of the Soviet atomic bomb", if you didn't know before.
  8. +1
    30 November 2024 22: 22
    Monstrously drawn-out comments with rare grains of common sense. Write concisely - respect others. To prove your point of view it is not necessary to reprint half of the great Soviet encyclopedia... or in your own words the development of world aviation. No need for banality.
  9. 0
    2 December 2024 00: 04
    A seaplane is an interesting idea, but it is too small for the sea, and for a river there will be problems with radio control.