Skip to main content

My First Sub 1g Airplane - 0.98g

To start off my blog I would like to start by going over my first chain of wildly ambitious engineering projects - micro r/c planes...




This was the first r/c plane that I built that weighed in at under 1 gram. I built this back in April of '07. It has a 5" wing span, 2" chord, and its about 6" long. The flight times were in the 4-5 minute range on a full charge.

It was constructed of carbon fiber rod from 0.5mm to 0.25mm in diameter. The covering on the surfaces is called OS film and is made by DuPont. It is on the order of 1 to 0.5 microns thick.

The electronics consisted of a 10mAh Lithium Polymer battery (1S), a 3.2mm diameter brushed motor driving a 1" diameter propeller, an electromagnetic actuator to control the rudder, and an infrared receiver which was capable of throttle and rudder control. Here is a full breakdown of component weights:

Weight Breakdown:
Airframe + Actuator: 150mg
10mah Li-Poly Battery: 400mg
IR RX: 120mg (76mg sensor, 44 mg receiver)
Stock 3.2mm Motor: 270mg
Prop: 10mg
Glue + Wires + Misc: 30mg

Total Weight: 0.98g

I went on to make some power plant improvements to this plane later on. I replaced the battery with a lighter variant and replace the brushed motor with higher power direct-drive and geared brushless versions. This brought the weight down, increased flight time, and increased the power:weight ratio. I also replaced the IR RX with a newer, smaller, lighter version. All this brought the weight down to 670mg. The wing loading was low enough where I could fly over my head and the plane would gain altitude due to the heated air rising from around my body. 


Original Post: 0.98g Plane @ RcGroups






Comments

Popular posts from this blog

3D Printed Mechanical Pencil

What better way is there to spend multiple consecutive weekends than sitting at your computer, redesigning a mechanism that has existed for decades, all to be able to 3D print something that can be bought at the store for less than $1? ... That's right, anything. However, when your co-worker throws down the gauntlet there is only one thing to do. Take it up.


This is how the 3D printed mechanical pencil came to be. Luckily though, it actually works pretty well and has enough style to spare.  
This pencil has 4 separate parts and was printed fully assembled as shown in the image below. Its about 6" long and 1/2" in diameter at its maximum, not including the pocket clip. It takes standard 0.9mm lead and 7mm diameter erasers. Three extra pieces of lead can be stored behind the eraser. I would have liked to do a more common lead size like 0.7mm or 0.5mm but the feature sizes required to hold lead that small are very difficult to achieve even on high resolution printers. Its …

3D Printed Dial Calipers

3D printing initially interested me because of its ability to create physical parts very quickly with nearly any geometry. By the time I had access to a 3D printer the ability to print virtually any shape had already been well proven and had even become common place. I was then introduced to the idea that multiple parts could be printed together, assembled, and captured. This may seem like a new concept but it is merely a new way of looking at 3D printing. The printer doesn't care how many pieces its printing, or even if they are connected.

I had seen adjustable wrenches printed already assembled. In the same fashion, I designed a c-clamp to try my hand at this concept. The camp worked perfectly. So then the question became "What's next?"


Dial Calipers. Yes. That sounded more than complicated enough with its gears, dials, and half dozen moving parts. I guess the irony of 3D printing a precision measurement tool with, what is normally considered, an imprecise manufac…

3D Printed Tape Measure

Going off the success of my 3D printed dial calipers, I decided to try to print something even more elaborate. But what to print? I contemplated several options but ultimately decided to print a tape measure.


Originally I didn't think a tape measure would be that interesting... I mean, it doesn't even have gears. Once I started piecing it together in my mind and determining the acceptable "cool factor", I realized that the parts count alone was skyrocketing. My calipers had 9 pieces, this tape measure would have well over 100... Now things were getting interesting.

I decided to attempt this based on the parts count and the fact, that if successful, I would be able pull out over 4ft of tape from something about 3" sq. Also, I had no better ideas at the time.

I designed the tricky parts first and printed little test pieces here and there to validate the design. Right around the time I starting adding all the cutouts in the main body (for cleaning purposes), it sta…