Code for WRT-T1 added on Github!

Hey everyone,

the source code for the WRT-T1, along with two tests I used during development are now available on my Github.

Drone Following Project #15: ROS development

I uploaded an early, early version of the ROS package that listens to the device and sends the info to the Drone. You'll notice that the first executable is called 'button_launch'. That's because the first part I want to work with is sending the Drone to TakeOff mode and Landing mode simply from pressing the Arduino button. The full executable will likely look similar though, as this functionality is also included in the full scope of the project. As you can see the use of the new bool message ('/Lakitu/Device/NewState') has helped organize things greatly. I still feel that I can cut down the amount of times State is subscribed to with some clever implementation, but I'm a bit tired for it now. My pseudocode stab is:

...
NCallback(Bool msg){
 ...
 ...
 ...
  r_nustate=msg->data;
}

SCallback(UInt8 msg){
  r_state=msg->data;
}

Subscribe('NewState',1000, NCallback);
if (r_nustate ==true){
   Subscribe('State',1000, SCallback);
} 

switch(r_state):
...

This way we only call on that extra subscriber when we need it, and rely on global memory otherwise. I have kind of PTSD from being really careful about the memory from working the Velodyne HDL-32E, since I was having to transfer a lot of pics and clouds at the same time.

 Once this is all hashed out, I'll begin testing using the special String publisher I made, then maybe the Drone's LEDs, and then finally the Drone actually taking off and landing. You can never be too careful when playing with the Drone indoors, or for an extended amount of time. Then it's on to the glorious world of IMUs.


On the topic of Velodyne, I'll be making my Velodyne code available on Github slowly. It will be a private repo, and it may take a while because I want to document it really well. I'll make an update when it becomes available.

Drone Following Project #11: Project Name!

This is a stupid and insignificant detail, but I've finally realized what to call this project! I originally had it under a Repo known as "AirCat", an obvious play on "AirDog", but I've found something much better.

Do you remember Super Mario 64?

Even if you don't, perhaps you recognize this character:

This is Lakitu. He got his start throwing spined turtles ("Spinies") at Mario in the original Super Mario Bros., but as time went on Nintendo chose to give him a more friendly role in future titles, such as an assistant in Paper Mario, the flagger in Mario Kart, and most importantly, the cameraman in Super Mario 64.

His significance as the cameraman was a pretty unique one at the time. While there may be an existing exception, not many thought to actually characterize the camera in a video game before, and most treated it as simply a mechanic. In Super Mario 64, Lakitu is actually the first character shown in the game world, flying down as Mario heads to the castle, and taking the place as his cameraman. From this point on, the player controls not only Mario in saving Princess Peach, but as Lakitu as well, helping properly angle the camera so that the player can more easily see what is around them. Today, I had the realization that this is not unlike the intended result of this project. Therefore I choose to name the project Lakitu. 

If I complete it in a timely manner, I'll be sure to make my own Super Mario 64 video as a demonstration. Hopefully I can attract the gaming community to this project and get the word out. It's good to balance yourself as engineer by surrounding yourself with clever and imaginative people. It could mean inspiration for your next part of the project! I foresee the implementation of Oculus Rift being a popular topic of discussion.


Bonus asset:

Drone Following #9: Soldering, State Machine, Github.

I've been quite productive since my finals (finally) ended.

First of all, my chips arrived! I was quite impressed with how small they were! The LSM9DS0 is about the length of half your thumb, and the level converter only a third of that. Not long after they arrived, I snuck out to the school's tech lab and soldered them together. It was nice to get back in the saddle and sit down with the ol' soldering iron. It feels like knitting, but with heat. My work isn't what it used to be, but I think it's enough to get the job done.

Next, I enjoyed my break exactly as envisioned. Tonight I spent the night doing some programming, the beginning of the drone following project. This consisted of creating an 3 state finite state machine. Right now it doesn't do much other than turn on LEDs in a sequential order and via the serial port tell you what state it's in.

But this is very important! After all, when I integrate this with the Drone controls, you don't want it ever going to the wrong state at the wrong time... This could mean taking off or landing at the wrong time. That being said, there was also some fool-proofing to be done-- for example, the Arduino reads super quick (sometimes), so you need to put a time delay in for the button press, or it may quickly transition between states. I handled this by having it hold for a second in a loop if the button is held. Right now all of the states are working as intended, so the next move will be ROS integration-- sending the state to ROS. From here, the Drone will read it, and respond accordingly. The states are as follows: Landing Mode, Takeoff Mode (indicated by a yellow LED) and Calibration Mode (indicated by a green LED). Calibration is where the Drone begins to follow movement.


Finally, I've made myself available on Github. It's been a while since I used it consistently, but I've realized that if I want to show people what I'm made of, I have to... show people what I'm made of. Therefore, I'll try to be consistent in uploading any code changes for your own viewing at my own github profile, Gariben. Here you can find the code for the state machine mentioned, as well as handy Fritzing diagrams and schematics. I'll usually include those in the blog, like so:

Currently, the code is housed under the "AirCat" repository. I didn't quite know what to name the project, since "Drone Following" will properly get me a pitchfork mob from an uneducated following, so I thought I'd just mimic the AirDog project that features the Drone remote, since the ideas are similar. Anyways, I hope to continue work on this project along with work to those I've dedicated myself too, so I'll try to keep everyone updated. Be sure to stay tuned to my Github for the latest-- it always comes at least a little before the blog.