Hey everyone,I haven't been on the site in a while and I am amazed at what is/has come out of this community in the past 8 months.Anyway, I made a blimp last year for a class at RISD taught by Paul Badger. The blimp follows people. Its based around the arduino, a pyroelectric sensor, and an ultrasound sensor. The code is quite simple: it scans for heat (IR at ~ human frequency) and once it finds a maximum above threshold, it moves towards the location of heat and corrects for height.I started out with some mathematically complex programming but soon learned that very simple rules performed satisfactory. I don't plan on adding any more advanced controls or processes: its simple, stupid, and fun.A video of the blimp is here.also on the video is some other stuff I've done including a drawbot that draws in polar coordinates, and a bicycle powered record player (hah, not done).
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Hey everybody...what batteries do you use to power your blimps? From searching around here, I see that Li Pol or AAA are two common choices. Chris mentioned something about having capacity for only about 300mAh with such a system. Is this generally agreed upon? What stops anyone from using 4 or more AAA in series. They seem to be pretty light, 7.6 g per energizer lithium, and provide decent mAh (1250 mAh ... yeah right). Other options, specifically rechargeable NiMH, like the rayovac ic3's, are quite alluring as well, although I assume these are heavier, potentially too heavy for the payload.So what am I missing?my setup is an arduino with two micro servos (one servo is constantly sweeping but this could be changed), a pyroelectric sensor (eltec 442-3), ultrasound, and two n20 motors. I would love to get at least ~1 hour of runtime off of a discharge of AAA's. I think Li Pol would better fit my desires however I would rather get the blimp up and running before I make that investment.I really appreciate it,Ari
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after much thought, i'm copping out of creating a UAV with video tracking.now the plan is to mount a decent video camera in a controlled environment in order to track infrared signals.blimps will have IR emitters on top, emitting some sort of modulated signal. with some fourier transform and the computing power of my mac, i can then locate and identify a given number of blimps in view.i'm trying to identify true (x,y,z) position of each blimp. i'm thinking of using some sort of pattern recognition (with led's set up in a simple pattern with set dimensions on top of each blimp) or i may just cheat and stick an ultrasound sensor on the bottom of each blimp. this would not be that good since any ground interruptions, like people, will greatly mess with the data. theres a bit to be ironed out of this scheme.anyway, the idea is that the blimps will be cheap (fast and out of control) and the computer is the brains, telling each blimp what to do. this way, i can get the computing power behind the video tracking. as of now i'm thinking of using JMyron in processing, since its easy to use, should be suitable, and i don't know Max/Jitter. I fear not being able to get enough data to have accurate fourier transforms (leakage, aliasing...?). the max fps of jmyron has me on edge.communication between comp. and arduino will use Xbee.been thinking of choreographing movement of blimps in a number of ways. ie: calculate thrust vector based off (x,y,z) and then blimps react accordingly. just a thought. could use some nice E&M potential fields as models.this is all one big changing thought. i just like the idea since it incorporates quite a bit and will provide a lot of new ideas to learn.
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I'm trying to create a blimp with ~50" envelope that can follow a moving target (a person) in a large open area with presumedly standing air conditions.going to plan this around the arduino boardInitial worries are:-the velocity of the target (this can be controlled to some degree, ie: area has distractions)-lag time of blimp will play a big part. Am thinking of integrating a buffer zone around target.-tracking system. I'd like to use active RFID (who knows) or could resort to ultrasonic. The ultrasonic/infrared combo looks real nice. Would like to stay away from just infrared for main tracking (this is still very rough). Probably use infrared or ultrasonic detectors for structural coordination.this blimp is supposed to be in a gallery or some other area with the intent of following one random viewer. A more complex model would pick the target using some form of video analysis. This is out of my scope right now.Ideally I would have the canopy resemble a cctv camera box. This piece is designed to play up the invasion of privacy of technology.still needs lot of work
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