Wildman Mach 2 and Custom Avionics Build

[diyaerospace]

Hello everyone.

After getting my L1 cert in December I haven't really touched HPR much. I plan to change that soon. Me and some friends will be building a Wildman Mach 2 kit that will be modified with a longer AV bay. Our goals with this are to get some higher altitudes, speeds, and experience with dual deploy.

Another goal is to continue development of my flight computer. I designed this device about a year ago and since then it has mainly been used for mid power rocketry and some active control stuff.
So far the flight computer has an LSM6DS03 to measure velocity and altitude, a barometer (will be removed for all these test flights), and a micro SD card slot to log data to.
I plan to add a GPS module to make finding the rocket easier and one of my friends is working on a telemetry system to add.
For the first flights I will have a COTS flight computer in control of parachutes.

As for flight testing I plan to start small to get additional testing done on my homemade flight computer.
Right now nothing purchased and I am focusing on software updates to my flight computer.

If you have any advice or you think I am about to step in it let me know

Thanks,
Walter

 

[Hobie1dog]

you guys are DEEP into it.

 

[tim cubbedge]

You should be able to fit 2 altimeters (1 with GPS) in the stock av-bay. That’s my setup. Another guy actually shortened his av-bay so he could fit longer motor.

 

[diyaerospace]

You should be able to fit 2 altimeters (1 with GPS) in the stock av-bay. That’s my setup. Another guy actually shortened his av-bay so he could fit longer motor.

At this point I will start by getting the electronics together, then I can get a better idea of how big the coupler needs to be.
My altimeter only uses THT components to allow me to switch out sensors (female pins soldered to PCB) and to be easy to produce.
This means it will likely be relatively bulky but time will tell.

Walter

 

[Starz]

You should be able to fit 2 altimeters (1 with GPS) in the stock av-bay. That’s my setup. Another guy actually shortened his av-bay so he could fit longer motor.

We actually plan on modifying the kit by replacing the stock fiberglass airframe with something longer to accommodate longer motors along with doing a tip to tip for it. We were looking for some kits that might have a longer body tube, but to no avail. Do yall happen know a kit that might have a slightly longer body tube?

Thanks,
Kendrick

 

[tim cubbedge]

We actually plan on modifying the kit by replacing the stock fiberglass airframe with something longer to accommodate longer motors along with doing a tip to tip for it. We were looking for some kits that might have a longer body tube, but to no avail. Do yall happen know a kit that might have a slightly longer body tube?

Thanks,
Kendrick

Just call @WILDMANRS and he’ll customize it to your needs.

 

[mikec]

YMMV, but I wouldn't really recommend a 54mm minimum diameter for this sort of thing. Something larger in diameter, say a 3" with a 54mm MMT, would give you more volume to play with.

 

[diyaerospace]

Update:

Software updates are going well. I am doing a software in the loop style of testing. I add acceleration data from previous flights into the software which then integrates acceleration to velocity then altitude. This way I can test drogue and main parachute deployment commands without actually flying the rocket.

In terms of the AV bay itself here is what I am thinking.

The bay itself will be stored in a fiberglass coupler with a band in the middle.
Each end will be terminated with aluminum bulkheads. Drogue and main parachute quick link attachment will be connected to U bolts that will connect to the aluminum bulkhead with nuts.

2 threaded rods will run along the AV bay. The altimeters will be screwed to a 3d printed sled. The sled will slide into the threaded rods. I will use nuts on either end to prevent the sled from moving around.

Pyro outputs will be done with either terminal blocks or WAGO lever connectors. What do you think?

I am also looking for a COTS altimeter that we can fly to get the chutes out. I must be dual deploy, have data logging ability, and ideally use and accelerometer but that is more of a bonus.


I attached a picture of how I will try and design the AV bay. If anyone is interested I found it in this thread.

https://www.rocketryforum.com/threads/the-avionics-bay-thread-post-your-photos.156649/
Thanks,
Walter

 

[diyaerospace]

Another electronics update.
Here are the components I am using.

High G accelerometer, ADXL375
Barometer, MS5607
Main IMU, LSM6DS3
GPS, Adafruit Ultimate GPS
Radio, Xbee 900 pro s3b
Processor, Arduino nano 33 iot
SD card or flash chip for data logging

More specifics:
8 pyro channels
4 servo outputs (not being used on this rocket)
30 by 85mm dimensions


The main philosophy of this design is to have 2 separate PCB's that connect with male and female header pins. This way you trade length for height.
I would also like each of the PCBs to function as a flight computer.

Here is what I am thinking:
The Arduino, gps, imu, data logger, and barometer will be one PCB.

A second Arduino(with a build in IMU), telemetry radio, and high g accelerometer will be a second PCB.

Two Arduinos are being used for a few reasons.
1)Increases speed of software
2)allows for more pyro channels/other outputs
3)since the radio and gps both communicate with UART connecting each to a separate Arduino means staggering signals is not necessary.


I have soldered together all the sensors on a protoboard that I plan to fly on August 12(an L1 attempt). If the data looks okay I will move forward to produce this design as a PCB and fly it on the Mach 2.

Thanks for reading,
Walter