Star drogue

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Jeffmhopkins

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Because of the winter storm, another drogue was sewn up.

Five gore, full French fell seams with embedded Kevlar.

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Proline/Rocketry Warehouse (took over the line) Used to have Starchutes 62" and 84" until sadly the seamstress unexpectantly passed on. Those who own them I suspect would attest to the design. Kurt
 
You make the most beautiful parachutes! How much would you charge for one of these? Ever consider going into business?
 
Thank you for the compliment!

I would be hesitant to put a price on these parachutes as the amount of time it takes to manufacture them, particularly on smaller parachutes. Because of the time it doesn't scale into a business model that well. Maybe a sweat shop.... It possibly takes 5x more time to sew a pattern like this vs straight gores (which takes way longer than a flat sheet)
 
I have followed your posts here as well as your website progress. I was particularly interested in your work with the remote descent as I am working on the same concept with my level 2 build. Will you elaborate on the radio and servo hardware/setup you used for your controlled descent? My design uses a Spektrum Dx6 transmitter with a spektrum receiver and servo on the rocket side. I am designing fold-out arms for the servo to pull the steering lines. The entire receiver, servo, battery and servo arms will be installed on a small sled and will be compact enough to fit inside a 2.6 inch x 10 inch payload space within the airframe along with the 1.4 meter parafoil main. It will be a complex recovery system requiring very specific and orderly packing. I have moving car experimentation and testing yet to do and calculations regarding deployment altitude and attitude control but am getting closer to a finished project. Should be fun. Keep up the fantastic work!
 
I've yet to complete a fully functional steerable recovery, but have most of the electronics and parachutes constructed.

To elaborate on the design though, the heart of my flight computer is a cortex m4 running at over 90MHz, full IMU, barometric pressure, and GPS (and some other goodies). Transmitter right now is a APC220 70cm transceiver running at 9600 half duplex. I have a 7 element yagi with LNA for the ground station and will also have a hobby receiver (either my dx6 or another module) for the manual control option.

Right now I've been doing flight tests in a 2" airframe for flight computer testing, and will be moving to a 3" airframe after a few more tests (mainly gathering base line data) for the start of autonomous recovery.

To ease control of the steerable parachute, a sled gets pulled out of the body tube to lay flat with 1 foot of separation between lines. Utilizing sailing winch servos for the high throw. I thought about continuous rotation servos, but then you need some digital tracking scheme.

Doing GPS waypoints on a car will definitely get you on the right track.

The parachute will follow a couple of steps:
1) fly a straight path via magnetometer, and calculate wind speed and direction vector
2) fly upwind to determine maximum wind penetration
3) determine if GPS location is within reach from altitude, possibly change landing locations from the table of landing zones
3) fly to landing zone (direction determined by azimuth plus wind vector offset)
4) spiral until landing, last 200-300 feet deploy large backup parachute for soft landing

I'll be able to flip a switch and control manually of I like also.

Overall a large project, but it's coming along. Since I'm doing EX motors, scratch built rockets, my own flight computer, and all the parachutes, it's taking some time :)
 
Well you are on a higher level than I! Adding autonomy introduces a new realm of development and ingenuity. My design is dumb control and I will be relying on real time GPS coordinates and live video feed via 5.8Ghz to track and bring back manually via remote with off the shelf 2.4Ghz RC equipment. I will be flying a CTI J530 to a thus far simulated mach 1.6 and 8900 feet. Environmental conditions must be ideal for a successful back-to-pad recovery but if a failure occurs I will just have to plot its coordinates and retrieve it the old fashioned way with my Chevrolegs!

Unsure if you are familiar with them I will recommend Adafruit.com as a source for MCU's. They have a plethora of small form factor pcb's which utilize ARM processors and also offer a substantial line of compatible sensor boards of similar form factor, all breakout-ready. In what languages do you write? How much programming is involved with your project? Do you source code from libraries or write all the logic yourself?

Addendum: Woops, I just noticed on your site you used a Trinket. Adafruit ftw!
 
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The cortex m4 is the Teensy 3.2 microcontroller, capable of being programmed in straight C and utilizing arduino libraries while running faster, more ram and more flash. I'll highly recommend it. All of the logic code is mine, however the sensor libraries are mostly unmodified.

All in all quite a bit of programming. Station software is mostly Java, I'm converting the telemetry to be viewed in real-time in Google Earth and a telemetry readout window.

Adafruit/sparkfun/mouser/digikey, all good for this kind of project. Right now the flight computer is on protoboard, but I'm going to be finalizing a PCB here shortly. 4 pyro channels, 2 servo channels, and all the sensors hopefully to fit within a 2" airframe if needed (mind will be in a 3", but I want options)

Edit//
Trinket was used for initial testing of sensors, later changed to a Teensy for its extra serial ports and memory
 
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You definitely have your work cut out for you! Looking forward to the YouTube video of a successful flight/recovery! Keep us posted!
 
Well you are on a higher level than I! Adding autonomy introduces a new realm of development and ingenuity. My design is dumb control and I will be relying on real time GPS coordinates and live video feed via 5.8Ghz to track and bring back manually via remote with off the shelf 2.4Ghz RC equipment. I will be flying a CTI J530 to a thus far simulated mach 1.6 and 8900 feet. Environmental conditions must be ideal for a successful back-to-pad recovery but if a failure occurs I will just have to plot its coordinates and retrieve it the old fashioned way with my Chevrolegs!

Unsure if you are familiar with them I will recommend Adafruit.com as a source for MCU's. They have a plethora of small form factor pcb's which utilize ARM processors and also offer a substantial line of compatible sensor boards of similar form factor, all breakout-ready. In what languages do you write? How much programming is involved with your project? Do you source code from libraries or write all the logic yourself?

Addendum: Woops, I just noticed on your site you used a Trinket. Adafruit ftw!

Not to steel the thread, but I would really like to hear more about how you are doing your RC recovery. I've been messing with mine for 2+ years and everything works except I've never gotten a clean deployment. Something always tangles and fouls the chute.

Shoot me a PM please.
 
Regrettably at a little over mach (onboard telemetry showed between mach 1.2 and 1.3) a motor failure caused the drogue to deploy at speed. The gores stayed together, but shroud lines were nearly half detached before depowering. A couple of seconds later, the drogue had slowed the rocket enough that the main parachute was undamaged.

For higher speed drogue deployments the shroud lines should be ran on top the gores, but this partial failure might have saved my hardware a bit of stress

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Jeff, I was parked right next to you at Higgs on Saturday. Next time I see you, I'll know who you are. Love to see/discuss what you are doing.
 
My configuration will utilize the drogue as a pilot chute to pull the parafoil main from its container once the main charge (Archetype) releases the container ripcord. Fall profile will be linear and mess-free, drogue affecting just enough drag to keep components in a descending fall profile order. One shock cord only and one short drogue/pilot chute cord are all that will be used. My design consists of only one separation point rather than the traditional two point/avbay config. How is yours currently configured?
 
That it all held together under power at that speed is testament to the quality of your work.
 
John, I'll be there next month and I can show you some other aspects of the project, no problem.

CORZERO,

This last launch didn't have steerable parachute components, it was supposed to be a test to verify the RF path and data flow to around 5,000 feet, I'll have to retest again next month before going to the next step.

I'm going to be using two separation points mainly for the backup parachute, to be remotely activated if needed upon tangle etc.
 
Sounds good. Keep us posted. You shouldn't have any transmission problems. Also, just an fyi, my most recent post was a reply to the gentleman who inquired about my setup and I replied without quoting him. What band and power are you transmitting at with your downlink?


So far I am getting >3km LOS uninterrupted video transmission using 5.8ghz band (playing with frequency and channels) transmitting at 600mw with an RHCP cloverleaf and a 5 turn helical RX on the ground. My waiver is only 13k AGL so I can't go much further for testing. 5.8ghz limited due to physical size of lower frequency cloverleaf TX antennas as my AVBAY space is limited in my 2.6 inch airframe. I have wonderful antenna resources if you are interested. Long 900mhz wavelength for gps and Raven data are easy peasy with 1/4 wave dipoles at TX (100mw) and RX (Eggfinder components with Raven data fed through EF TX).

Good luck
 
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I'm doing a bidirectional half duplex serial link at 4800 through two 70cm APC220. Transmission power is only 20mW, but with a 6 element yagi and LNA on the ground station with clear line of sight I've been pleasantly surprised with the range.
 
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