Week 3: R&D a.k.a Research and Development

Finally, it’s you again! I’ve been waiting to share more about my drone delivery adventure with you over the last week.

Oh, and what a week it’s been!

As you can tell by the blog title, I’ve been doing a lot of research and development on my drone. I began by sketching away, leveraging years of art classes to render prototype designs for my drone. There are a multitude of factors to consider when building a drone from scratch, like I am. And over this week, I got lost in all of these details.

Here’s a list of all the important questions I had to ask when designing the drone (this might not even be all of them!)

• How much weight should the drone be able to lift?
• What should be the weight of the drone?
• What flight controller will be compatible to program with my Raspberry Pi (not edible by the way)?
• How much KV should my motor generate?
• What must the diameter of that motor’s shaft be?
• How much current does the motor use at peak operation? What about at idle?
• What kind of ESC will be able to handle this amount of current?
• What kind of power distribution board can manage that current x 4 (because there are four motors on my drone)?
• What kind of batteries will be needed to power this drone for about a half hour?
• What kind of propeller should I use to generate the most efficient flight trajectory?
• Should it be made of carbon fiber, wood, or plastic?
• Will I need to design an adapter so that it can fit on my motor?
• What material should I use to build the drone frame?

The questions go on and on and on. A lot of last week has been research into each of these questions, parsing through forums, attending courses, and speaking with personal contacts like my external advisor. I haven’t answered all of my questions (and new ones constantly appear), but I’ve gotten to the point where I can make decisions and proceed. Here’s what I’ve decided.

For the frame, I am using carbon fiber tubes that are joined with 3D printed parts (I have designed). It will use a modular structure to easily expand the storage for electronics and batteries so that in case I something doesn’t go as planned, I’ll be able to alter the layout. I’m doing this by creating a sandwich-like layout for my drone where there will be electronics, then a layer of 3D printed material, then another set of electronics.

As for the parts, I’m ordering a 320 KV drone motor because of my payload requirements being the average Amazon package (about 5 pounds or so). Using a low KV drone motor for a high payload application is beneficial due to its efficiency, torque, and reduced stress on the motor. This choice will make my drone smoother, with more stable flight characteristics, optimizing the drone for lifting variable-weight payloads while extending flight time and ensuring longevity. I’m still deciding on a propeller, but I’m narrowing in on a carbon fiber set because they are far more rigid and provide much more rigid flight dynamics.

I’ve ordered all of the compatible electronics as well. I don’t want to bore you too much with technical details but I’ll be using a peak current of 160 Amps, so I simply bought parts that can withstand that current.

Now, while everything arrives, I’m continuing my education on precision drone delivery. I purchased a course from the Drone Dojo that gives me step by step instructions on how to implement various modules of my project. I’m also using CAD software to design parts that will hold the drone together. I’ve already begun 3D printing them and running test-fits so that I can redesign flawed parts.

And with that, this week is a wrap! I can’t wait for all of my parts to arrive so that I can finally take you all to the skies.

Until next week,

Aidan Peter