Sunday, August 17, 2014

Hamilton Pool video!

Earlier I posted some pictures from my trip to Texas. Between the two GoPros we brought with us, we managed to take enough footage to make this short video of Hamilton Pool. I really enjoyed compiling this video:



It was a lot of fun and very beautiful place to visit. Next time I go back to Texas, I be bringing more accessories for the GoPros so I can get even better footage of the natural areas.

Wiring up the Mini-Quad

Last night I began wiring up the mini-quad starting with the motors and the "dirty" section where the speed control is located. I am using the 12amp 4in1 ESC from Ready to Fly Quads, so all 4 motors are wired into the printed circuit board. I am using 18awg wiring from the ESC to the motors, and 16awg for the battery leads.

Soldering 18awg extensions to the motor leads:
 I shrink wrapped each lead, and then covered the bundle with expando to clean things up:
 Soldering the first motor to the 4in1 ESC, maybe a little heavy on the flux:
 All motor leads lengthened, just need to solder 3 motors to the ESC still:
 Completed "dirty" section with all motors wired, power leads, and capacitor added.

I also began wiring the "clean" section, but because it was so late and I was excited to get things done, I didn't take any pictures. I will go back and do that later.

New G10/FR4 Arms for the mini-quad

The new G10/FR4 arms have arrived! Thanks to Twitchity in the Flite Test Forums again!

I wasn't really getting anywhere as in regards to having the aluminum arms manufactured, so I went ahead and redesigned them to be made out of G10/FR4 plate. The plate used was .125" thick which provides plenty of stiffness for the application.

 G10/FR4 Arms ready to be installed:
Arms assembled with "dirty" frame section:
Spacers required for fitment of new arms:
New arms also required new nuts and bolts:
Slots cut in arm for zip tie to secure motor wire leads:

I am pretty happy with these arms and I will probably stick with them since the aluminum arms were going to be costly. I went ahead and had two sets of these made, so chances are I will build another mini-quad in the near future.


Tuesday, August 12, 2014

Mini-Quad GoPro Housing V1

Just a quick screen shot of the GoPro housing for the Mini-Quad. I've already sent this part off to Shapeways for printing. I chose to have it printed in "Strong and Flexible" material dyed orange. It will look just like the arms in the previous post. Although in this case I am pretty sure the printed part should suffice as useable in the actual final design. Once I have the piece in hand, if it needs any added strength I already have some ideas in mind to beef it up while keeping the weight low.


3D Printed Arms for the Mini-quad?

This is more for fitment testing rather than functionality, but I decided to take the design I had for aluminum arms for the Mini-Quad and have them 3D printed by Shapeways. As you might have guessed the design is inspired by the Lumenier QAV400 arms. While they are similar I have added my own design features and lightened them where I could. I ran a quick FEA on the aluminum version and they should deflect less than .005" under full thrust (using 6061-T6 aluminum). This is with the mounting points fixed, so most likely in flight they should flex even less.


I had them printed out with the "Strong and Flexible" plastic material on their website. They look pretty, but they definitely have noticeable flexibility. I went ahead and installed them on the frame with the motors just for kicks and giggles. It definitely wouldn't be flyable with these printed arms. I would have to beef up the design a lot more if I wanted to print useable arms.


Unfortunately shortly after I received the printed mock-ups, I was informed by my machinist friend that he probably wouldn't be able to machine the aluminum versions due to work issues. Because I want to keep the project moving along, I have already re-designed the arms to be made out of flat .125" G10-FR4 plate, which is currently being machined by Twitchity from the Flite Test Forums (he also milled my frame plates). The new arms should work out good, but I was really hoping to have a unique mini-quad with machine aluminum arms (which would eventually be anodized).

Texas Swimming Holes!

Last week I had the pleasure of visiting Texas for the first time with my other half. She was born in Texas and still has family that lives there. Unfortunately the circumstances that led us to take this trip were due to the passing of a family member.

However we like to make all of our trips an adventure, and my other half, well lets just say she manages to find all the cool and interesting things in every state. She is like my own personal travel agent and for this trip she led me to some pretty cool swimming holes in Texas.

The first place we visited was Hamilton Pool near Dripping Springs Texas. We left our hotel a little after 7am to make the drive there. Most of the pictures I have seen don't do this place justice. It's really something you have to see for yourself. Below are a couple pictures I took, mostly with my Nikon D5100, but also a few with my GoPro Hero 3+ Silver (basically anything that appears fisheye was taken with the GoPro).





The water was less below 70*F which seems cold at first but is very refreshing in the heat of Texas, which explains why this place is so popular. We actually arrived 15mins after the park opened at 9am and got right in, but if you don't get there early enough, you'll be waiting outside the gate until parking becomes available. There was limited parking and the park rangers hold vehicles at the gate once it is full. This was nice because even though the place was busy, the pool never got overcrowded.

We ended up staying for 4hrs without realizing how long we had been there. It was so nice we didn't really want to leave, but we didn't pack our lunches like some of the other visitors. On the way out there was a 20-30 car line of people waiting to get in, so I bet they were happy to see us leave and provide an opening.

The next place we headed on the way back to our hotel was Jacob's Well in Wemberley Texas. Interesting enough this place is completely open to the public. There was a parking area, but there were no park rangers or anything like that; just some trails leading to the spring, and a couple signs with rules written on them. Rules like, no dogs allowed, no jumping off the rocks, swim at your own risk, etc. Pretty much all of them were openly broken by those who visited Jacob's Well. Which is also why this was such a fun place!

Jacob's Well is an underground cavern and spring. The water was significantly colder than Hamilton Pool, especially the closer you swam to the well.

We spent most of our time hanging near the well with the locals watching as people took turns jumping from the rocks into the well. It was fun watching as some people jumped with little hesitation while others debated whether they could make it. Typically the kids had a little less fear and just went for it. My other half was feeling pretty adventurous this day too and came very close to taking the dive after a couple little boys who were continuously jumping told her it was easy!

She almost did it, but I think after standing on the rock long enough it really makes you rethink what you are about to do! I think if we ever go back here we'll probably both try to jump from the rocks because it was all we talked about on the way back to San Antonio afterwards.



Several people at Jacob's Well had GoPro cameras with GoPoles, one guy even had a Phantom 2 quad copter with a gimbal. I wish I had one of my copters with me because this place would have been great for aerial shots. Unfortunately I don't have a good way to transport any of my equipment when traveling by plane. I debated getting a travel case for my QAV400, but the price has been holding me back. First action item after I finish the mini-quad is to spec out a good Pelican case. Since it is smaller it will be easier to get a carryon size case for, and it will probably be cheaper than getting a case for one of my larger rigs.