Blog posts

2024

Wildflower Seeds

2 minute read

Published:

We moved to PA in 2023 and our property has a rather large and very plain looking power line easement. Previous owners had been mowing it every few months and as a result the plant biodiversity is pretty low consisting of mostly Timothy Grass with a few blackberry bushes spreading out of the woods.

Inspiration

I like to look at wildflowers damn it. Going outside and collecting seed heads from wild plants on the roadside while effective still means I need to spread them on the easement somehow. I figured why not make something airborne? Enter the seed drone!

Hardware

The drone is a pretty common custom made 5 inch prop FPV drone, its running a betaflight firmware (4.5.1). The seed deployment mechanism consists of a 9g servo and a rubber band. The servo proved to be the most frustrating part of this build. The drone flight controller is a SpeedyBee F7 V3 with the servo signal line going to motor pad 5 (M5) with the ground and +5v to their pads. Drone Electronics The motor controller outputs more than enough power for a 9g servo, that servo rotates the control horn releasing the rubber band and flinging seeds. Depending on the type of seeds they can be wind dispersed or scattered by gravity alone, below is an example of wind dispersed Joe Pye weed and wild lettuces.

Wild Lettuce Wind Dispersed Seeds Joe Pye Weed Joe Pye Weed

Other seeds like to be in a soil seed bank and they can be packed into “seed balls” made of clay and compost. Seed Balls

Still others are perfect for dropping loose but packed for flight using “natural materials” found around the forest. Seed Packet

Demonstration of the loose seed deployer in action.

Drone Dropper

Software

By default Motor 5 is mapped to output B07, since I’m not using motor 5 for a flight motor we can redefine Servo 1 to use that output.

# resources
resource MOTOR 5 NONE
resource SERVO 1 B07

Next we need to make sure that CHANNEL_FORWARDING is enabled in betaflight, I’m using channel AUX 1 for the seed deployer Servo 1 with that mapped to a pushbutton on the radio transmitter. By default the channel_forwarding_start param maps AUX 1 to Servo 1

References:

https://betaflight.com/docs/wiki/guides/current/servos-and-servo_tilt-for-3-1

https://youtu.be/L-6r2iX1p6s?t=804

Drone Servo

MycoMIDI - Mushrooms as musical instruments

1 minute read

Published:

Every so often when I’m dealing with a lot of stress I end up making strange projects. I had a dream where I had synesthesia, movements of muscles and joints had distinct sounds and actions like walking or running played different melodies. As a result I ended up learning about human nerve action potentials and their electrical spikes.

Inspiration

My goal was to turn bioelectrical signals into “music” of a sort, attaching electrodes to myself would be quite uncomfortable long term but I was already growing Oyster and Lions Mane mushrooms for food.

Plantwave - https://plantwave.com/

BioAmp-EXG-Pill - https://github.com/upsidedownlabs/BioAmp-EXG-Pill

Hardware

On a whim I pulled a retired mycelium block from the compost and hooked some electrodes to it. The signals were barely noticable on an oscilloscope so an amplifier was needed, enter the BioAmp-EXG-Pill!

oscope

With the amplification sorted out the signal needed to be converted into a MIDI signal, a Raspberry pi and ADS1256 ADC was pulled from the parts bin with each channel assigned to an amp.

Signal Amp

Bio Amp

All wired up

Proof of concept

Fruiting mushroom block

Mushroom Blocks

When the blocks are done fruiting they get retired to the great outdoors and then composted

Retired mushroom blocks

Software

https://github.com/rjmendez/MycoMIDI/blob/main/mycomidi.py

2019

2018

ViaSat rm4100 Console Access

26 minute read

Published:

This is part of a series on reversing the ViaSat rm4100 satellite modem.

ViaSat rm4100 Memory Dump

16 minute read

Published:

This is part of a series on reversing the ViaSat rm4100 satellite modem.