df8m1

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  • Main Canopy Size
    120
  • Reserve Canopy Size
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  • Home DZ
    Napoleon Skydiving Center
  • License
    C
  • License Number
    29633
  • Licensing Organization
    uspa
  • Number of Jumps
    1550
  • Years in Sport
    12
  • First Choice Discipline
    Formation Skydiving
  • Second Choice Discipline
    Freeflying

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  1. df8m1

    New AAD made in USA

    I have been getting a lot of questions such as "what makes this AAD any different?" and "Can a jumper change the activation altitude?".. I am finding that I am too close to this thing to keep it simple when I try to answer those questions lol, so I thought I would post some graphics from one of the PIA seminars I put on in Dallas. Question: Can a jumper adjust the activation altitude? Answer: No.. This AAD actually adjusts the activation altitude, within a window, based on the jumpers descent rate. At a descent rate of 170ft/sec or slower, the activation altitude is 998 ft AGL. Descent rates above 170ft/sec but bellow 250ft/sec will result in an activation altitude between 1200 ft AGL and 998 ft AGL. Speeds above 250 ft/sec will activate at 1200 ft AGL. The goal being to have an open reserve over head by 500ft AGL regardless of the jumpers descent rate through reserve deployment. The current AADs use a fixed activation altitude regardless of the jumpers descent rate which puts all the variable tolerance (how far a jumper will travel during the reserve opening sequence) on the bottom end (between the fixed activation altitude and the ground). In contrast to that, by automatically increasing the activation altitude as the jumper's descent rate increases, I are attempting to put the variable tolerance on the upper end and provide a reasonable cushion between jumper and the ground by the time the reserve is open and over head. There is an exception to that where the AAD will delay activation, and that is if a main deployment was detected prior to reaching the activation altitude. This delay is based on the jumper's real time descent rate and a reserve canopy over head altitude of 300ft AGL. This delay allows any usable time for either the main to open (if the jumper pitched low and the canopy sniveled) preventing a 2-out, or allow the jumper to use any valuable time to try and deal with a main malfunction and clear the air above the reserve prior to automatic activation in an attempt to prevent a duel entanglement malfunction. This ability eliminates the need for the jumper to manually adjust the activation altitude. I would like to note that the jumper will be able to adjust the DZ elevation for a remote DZ which is one way some jumpers are raising the activation altitudes on their AADs now, but it should be noted that doing this also raises the altitude where the AAD will no longer fire, usually around 300ft ish AGL. Question: "What makes this AAD any different?". One thing is that this AAD is able to identify where it is during a flight. The Situational Awareness graphic shows the flight mode changes that this AAD actually identifies every jump. This ability allows this AAD to resist firing in an aircraft regardless of the altitude and descent rate. It also allows for the detection of a main deployment, if it has malfunctioned or has opened and is flying, and if so, locks out the ability to fire regardless of the jumper's descent rate while under canopy (preventing a two out due to a high performance landing). It can also detect a cutaway, and if a reserve deployment is not detected in 4 seconds, it will determine an activation altitude based on the jumper's real time descent rate and a 300ft reserve over head altitude, and if a reserve deployment is not detected by that altitude, the AAD will activate. This allows for a delayed reserve activation provided the altitude is available, as there are times when a delay between a cutaway and reserve activation is beneficial, and I do not want to take that "pilot in command" decision making power away from the jumper. I am however comfortable in saying "times up"..lol. The Dynamic Activation graphic below shows the difference in activation altitudes based on speed and if a main deployment has been detected or not.
  2. df8m1

    New AAD made in USA

    I jumped an Alpha all last summer and there will be some Military Betas in the air this summer. I pivoted our focus from the Sport AAD to the Military one as the U.S. Military is looking for a replacement for the Cypres-2 and Vigil AADs. (The Sport and Military AADs are different in regards to hardware and software). I would recommend that you go ahead an get an AAD, and when this one is ready, you will always be able to sell the one you got as a stopgap. I am excited about live testing the Military AAD this summer.. If the U.S Military does not give us the nod then we will pivot back to the Sport version. I am very pleased with how both AADs are evolving as we improve / refine the algorithms, and address issues that could arise from potential scenarios; of which there are an incredible amount lol.. The algorithms are performing at a level that I never thought possible when we started these projects.. It is like watching a child grow up lol.. I will try to keep everyone updated this summer.
  3. And now a jumper who is whistling in can think to themselves, "Boy... I'm glad my AAD battery is only 13 years old" lol.. Batteries are cheep IMO
  4. df8m1

    Altimeter Inaccuracies?

    Please clarify the distinction between deployment and deployment detection, and how canopy detection differs from
  5. df8m1

    Altimeter Inaccuracies?

    Full Disclosure: I am working on a new AAD.. This discussion made me take a look at the AAD altimeter readings from the point where the deployment is detected and when the vertical descent rate is
  6. df8m1

    New AAD made in USA

    Thanks for the input. I was not sure if Vigil retained the "off set" for a different DZ landing altitude. This AAD will have a preset reserve activation of 1000 to 900 ft, and will automatically increase the activation altitude proportionate to speed above XXX ft/sec to compensate for the additional distance traveled during reserve deployment due to the higher speed. The goal is to have an open reserve at a consistent altitude regardless of the jumpers descent rate at the time of reserve deployment. The Max increase will be 250Ft which would be at the Max TSO Placarded speed. This automatic increase in altitude above XXX Ft/Sec speed is to help prevent jumpers going in at reserve line stretch after an AAD fire at extreme free fall speeds. Now I know there are people probibly screaming at their monitors that automaticly increaseing the Resereve activation altitude will increase the chance of a two out situation. To address that, this AAD is able to detect a main deployment, and if it has detected a main deploument it automaticly adjusts the Reserve fire altitude to a lower "point of no return" altitude which again is dependent on the jumpers descent rate. If they have a high speed bag lock, they will not have as much time to deal with it as they would with a lower speed malfunction. The Smart Reserve Activation altitude in intended to allow as much time for a normal AAD fired reserve activation to occur, prevent a reserve fire from low pitch and snively canopy, and allow the jumper as much time as allowable to clear a malfunction before the AAD fires the Reserve should it be necessary. Now that I have gone off into the weeds.. My original thinking was to maintain the DZ Offset until manually cleared or the AAD is turned off. The key aspect with this AAD, as with any piece of equipment, is to not only know how to use it, but to know what it is going to do. It is starting to get exciting now that I am at the point where I have to nail down the little details..
  7. df8m1

    New AAD made in USA

    Quick question I hope... In regards to offsetting DZ altitude... As far as I am aware, every AAD currently available requires the user to set the off set before every jump, or in other words, the offset clears upon landing and will need to be reset before the next jump if the jumping back into the same DZ from the same airport. I do not recall hearing people grumbling about having to off set the DZ altitude for every jump, and there has to be a few DZs that take off from one location and the DZ is at a different altitude. Would it be preferable to have the offset remain until either the jumper clears the off set or the AAD is turned off? Or is requiring it to be set on every jump not a big deal? Thanks in advance :)
  8. df8m1

    Air Speed

    What you said lol... I built some parachute flight data recorders for the Forest Service Smoke jumpers several years ago now. It had a pitot tube that measured indicated air speed. It was calibrated in a wind tunnel. Depending on what you are looking at doing, you may want to look at model rocket / airplane airspeed measurement systems.
  9. df8m1

    New AAD made in USA

    Sorry for the delay.. I believe C, or some form of it anyway... The cool part is the firing software is not part of the operating system software, so we can put the firing software on any hardware platform that has the instrumentation we need and can supply data at the required rate. To demonstrate this they are going to install it on a smart phone.. For jumpers this means nothing, but to a competitor who would be interested in buying the firing software, it makes it really easy to integrate into their AAD platform.
  10. df8m1

    New AAD made in USA

    It all depends on the operational range of the AAD. If the goal is to mimic a mechanical AAD, then the current AADs do that very well, there is one for every individual discipline, but when used outside that discipline the performance may not be a good match. For example a wingsuit and a speed AAD. But if you want one that will handle multiple disciplines on the same jump, guard against firing in an aircraft, reduce the chances of a two out because you set the firing altitude higher, etc, with out sacrificing performance at any point during the jump, then it gets a little more complicated lol.. The current AADs work well when used within their specific performance windows, and I would say that covers probably 80% of the sport jumpers, but does not meet the new military requirements. The military is requiring higher performance AADs that will not fire in an aircraft. The trick is to make the complex as simple as possible. Ten years ago we covered a 4X8 white board with logic written in small print. Today, we are exceeding the functionality of all that logic with refined logic that takes up less than 1/4 of that space. Our process is to identify function, for example, to delay reserve deployment if a main deployment was detected in an effort to prevent two out at 900ft because the jumper was low and sniveled big time... Then come up with a process that will achieve that, (not worrying about complexity at that point). Test the logic using test data in a simulation, and over time refine the logic over several iterations. We are still in the testing the logic phase for a lot of this system, so things may seem overly complex and awkward, (for lack of a better term). Two months from now I will probably look back at the logic I am playing with now and say to my self why the hell did I do it that way??! lol The process can seem messy and can make some people uncomfortable lol.. I guess that is why manufactures keep things behind the curtain.. I think there is value in the questions and comments.. Monosa's post has me thinking again about some things that I set aside until we were ready for them.. I think it is better to have a lot of options and choose wisely, then to not have any choice. Fixed speed and altitude works for the majority, I think everyone else shouldn't have to compromise.
  11. df8m1

    New AAD made in USA

    Good questions!! I don't really want to get into too much detail as to our processes and such, but I will attempt to walk the line so to speak lol.. I am not a programmer so I am out of my area, but in regards to validating the algorithms, making sure they respond predictably and consistently, for example after a change is made, we have "gold standard" data files that we rerun in place of sensor data which allow us to identify any differences in the performance of the code. The processor thinks it is reading data real time, as if it were in the air. If there is the slightest difference in the out put we will see it. The programmers also asked me to make special test data sub sets and that can be injected at any point during a test, even garbage data to simulate a bad sensor reading. This is a very time consuming process that has to take place every time a change is made. Nothing really special about the process.. This is of course in addition to use of best coding practices and external debugging and validation software. As for redundant hardware, and how it would react to a malfunction.. The only actively redundant component (at this point) is the baro pressure transducer, and that is mainly due to the hardware being used for multiple applications. (One application uses one transducer, another uses the other)... One benefit to having two is we can compare the readings during the self test.. If they differ too much, then a fault code will be set and the AAD will shut down. If the baro pressure transducer that is being used drops out during a jump, the other one will be used until the jumper has landed, at which point it will shut down. The system monitors every communication action on every buss, and records faults if there is a momentary problem detected. With the Sport AAD, the baro transducer is on a different buss than the other sensors, so if, lets say, the accelerometer froze and did not release the buss mid jump, then the AAD would go into limp mode, and become a good old fashioned speed and altitude AAD, relying on the baro sensor for the remainder of the jump. Same would go if the baro sensor froze, then the back up one would be used until landing. The alternative is to just shut down, which we may end up doing for simplicity sake. Just because something can be done, doesn't mean it is the best course of action for every situation. We are testing different ways to deal with different scenarios, and evaluating them as part of the development process. If the processor were to crash and reboot there are a lot of different things that "could theoretically" happen, the most likely would be that the power would turn off and that is that... The worse case is if it "hiccups", where it stops looking at the data for a period of time, then comes back on line and sees a dramatic difference in readings and reacts unpredictability. That is why we do the testing mentioned above, to see how it reacts and put in place checks to detect the hiccup. The unsaid concern is "will/can/would it fire when it should not?". The firing circuits are designed with several layers, requiring a sequence of events to take place in the correct order, in order for the cutter to fire. In my mind that is the best defense if the processor should really shit the bed. That being said, there are other ICs on the the boards that have processing capability that could be used as a check for the main, which is something that we have talked about. That however adds more complexity, but it may be worth it.. Aircraft have three computers for this very reason. It is the "what ifs" that keep me up at night.. The systems programmer has worked on guided missile systems, military radar systems, and autonomous vehicle systems. He has said that this AAD is more complex than anything he has worked on before lol.. It has to almost think!
  12. df8m1

    New AAD made in USA

    After reading your post I am having second thoughts!! I guess if it were easy everyone would be doing it lol... And you are correct about the market being small, especially when compared to the development costs. When I talk to potential investors about the market size the standard answer is "it's too small". A comment was made pointing out the military market... Currently the USA pays around $5,000 for a military Cypres, and the military are tired of that. At that price point, yes, it is worth doing.. but the military is looking to drastically lower the cost of AADs, and they order sparatickly in little batches which is not ideal.. I won't speak for the other AADs, but our military and sport AADs are quite different. The military has requirements that the sport does not need, and the sport has requirements that the military does not need. Each system is designed and validated for the end user market so it is like developing two separate AADs, with two different revenue streams to pay for their creation.There is a reason why the current AAD technology has not been updated in 25 years lol... Fortunately we are at the fun part now. I have been test jumping an Alpha unit and we are building drop test dummies that are brave enough to get out at 500 ft to test the Static Line AAD, and 1,500 ft for the sport AAD. The cutter is coming along nicely and summer is right around the corner.. or so they say.. But seriously, we do appresheate everyone's words of encouragement. Sometimes I stop for a moment and ask myself, what the hell am I doing?!
  13. df8m1

    New AAD made in USA

    Attached are three pics of a fired blade and anvil. Anvil material is 17-4 SS at 34Rc. Blade is 440C SS at 58Rc. Also a pic of an assembly view of the finial design cutter and a pic of the body by itself.
  14. df8m1

    New AAD made in USA

    At some point I will. With this first batch of cutters I was testing different cylinder materials, and loop hole / grommet face geometry, but the cutting aspects were the same (same blade material, hardness and geometry). For some tests, I turned the blade as much as 30 degrees off perpendicular to the loop, some the loop holes were in slightly different places / sizes, etc.. The last version (not in the video) was shaped to help with rigging. My intent was to reuse the blades, but it is too much of a PIA to get them out once they are fired lol.. The blades hold up well. If I think about it I will take a picture of a used blade. Now that I am happy with the cylinder material and, internal / external aspects, I will make more blades and cylinders based on the last design, and evaluate overall performance in a rig. I will also make more videos from different angles, put them together and up load them to YouTube. I just thought people would appreciate a sample vid.
  15. df8m1

    New AAD made in USA

    Gotcha.. Yes, it is a single edge cutter like the Cypres and I also believe that MarS is now using a single edge cutter as well. I posted picks of my blade a few posts back. Also using a standard gas generator for power just like the other cutters out there. My cutter has some features that are different than the Cypres cutter, they are minor, but were done for a reason.. I will get more into that in time.