So What are Everyones Navio Projects?

So I’m stuck waiting for a new transformer for my foam cutter(current one isn’t powerful enough for the 5ft wings I want to build) so my project is on hold for a couple days. In the mean time, I was curious what everyone else is planning to do and/or has done with their Navios.
I am working on an long range aerial photography platform, and the Navio is going to serve as a data source for telemetry and a fail-safe in the event of a lost connection. I’m not entirely sure what I am going to do with the inputs, but I have thought of a few ideas: Stall warning, cylinder head temp, fuel level, high precision thermometers on each wingtip(Temp difference can be used to find thermals), and angle of attack sensor. I am also experimenting with a compact fire suppression system using 12g CO2 cartridges just to see if I can actually make one that works.
Another experiment I am trying with this plane is using some aluminum and carbon fiber arrows with broken tips, that I have around, as a cheap way to spar foam wings. I will pre-stress the spars the spars buy bending the wings down slightly while inserting the spars. I will let you know how it goes.

Hi Bradley,

My project goal is to build a autonomous rover, including First Person Video similar to this youtube vid https://www.youtube.com/watch?v=r66T7y_nsdM

hugo

@Hugo Certainly looks like a fun project. Are you doing the full telemetry like in the video?

well my goal is indeed FPV and to get it as autonomous as possible. also looking into GSM module(old mobile phone or data dongle) so it can rover away from the ground station really far.

but… first things first … I have zero experience with APM or autopilot stuff …
Actually I have some bigscale race cars they are gas powered so I need to switch to a more electric powered platform.

choices:

  • what transmitter i need? 6 channels minimum for copter later, do i need 8 channels? I am afraid I regret buying a 6 channel transmitter…
  • what rover platform? I am looking into 1:8 scale crawlers at the moment… any suggestions welcom
  • the APM:rover site at DIY drones is intersting but not al lot of people seem interested in rovers… more in flying drones…

anyway

Hello Hugo,

Regarding the choice of transmitter:
Simple rovers only need 3 channels:

  • Steering
  • Throttle
  • Mode switching

But it would probably be better to buy a good 9-channel transmitter in case you’d like to switch to another platform in the future. Another important feature to look is the support of PPM output in the receiver, so you don’t have to worry about PPM encoder or some kind of another specific converter.

Hi everyone,

I am going to put my Navio in a FPV rover, too.
Actually it is already in the rover, but not doing anything at the moment. My pixhawk is still in control.
I am using a Dagu Wild Thumper 6WD Chassis 34:1. It works great, but I had to change a few things. I just could not stand the way Dagu fixed the axles. They just used self-cutting screws as the pivot, going through the 4mm holes in the aluminium. Not only that, but they were screwed in at all angles, not one straight. I used a combination of 6 and 4mm brass tubing and M3 screws to change that.
This is what it looks like right now:

@Hugo: Do not use/buy a 6 channel radio, you will run out of channels real quick. A rover is not as weight limited as a multicopter or a plane, so you can add quite a few things. Right now I have a 2 axis gimbal, lights and a sirene and I use 7 channels already.

Hi Guys,

So I am thinking of buying this RC kit http://www.futaba-rc.com/systems/futk9200-10j/index.html

futaba 10J 10 channels.

with this reciever R3008SB from the site “The R3008SB is a T-FHSS telemetry-capable receiver that features S.Bus and S.Bus2 compatibility and 8 conventional ports.”

Now I cannot see if this S-Bus is actually ppm compatible? can anyone enlighten me here?

thx

hugo

guess not see here

so what recievers do have ppm compatible to NAVIO out of the box?

thx

hugo

Hugo, there’s an SBUS to PPM converter available, so SBUS receivers should be okay together with it.

I’m making a quad, and to that end I’ve written an 8 channel PWM to PPM converter for the Arduino. available here… pwm2ppm But I’ve not tested it much (and not with the PI version of the Ardupilot code yet, I tested it with the Navio/C++/Examples/PPM decoder). So I dont recommend you buy a transmitter/receiver based on this, before more testing (pwm systems seem to be fairly common tho).

But if you happen to have an arduino lying around and a pwm transmitter/receiver combo :slight_smile:

Hi Mikhail,

I am looking for a reciever that does not need an extra ppm converter.

will tarantis X8R do the trick? or is that sbus also?

i like the opensource part of that kit, any experience with that in combination with NAVIO?

thx

hugo

Hugo, Taranis is also S.bus. We use Futaba gear and converter. Take a look at FrSky receivers, many of them have CPPM. For example D8R-II PLUS.

now human response times are pretty low, its been shown that 1/5th of a second is normal for human-car reactions (at best). if you are manually controlling the transmitter then it wont make a lot of difference. S-Bus is apparently something futaba created to monopolise the RC area. (see wiki) If you need the radio for faster response times, then you probably need something better than s-bus more a digital system. Like wifi! :slight_smile: (tho that loses reliablity)

We seem to be taking over this thread. perhaps a new one for comms would be a good idea.

The quadcopter. I am intending on extending to a Navio quad and using their examples for my own ends… umm, mwahahaha?

So now that my project is in a more mature state I thought I would share it. I am using the Navio in my PhD research on aircraft performance based flight testing, specifically power required. The idea behind my research is to utilize accelerated flight to back out power required versus the standard PIW-VIW method which requires steady state conditions. The Navio does not provide all of the necessary data I need so I created an additional board that stacks between the RPi and Navio. This additional board has 3 differential transducers for airspeed, angle of attack, and side slip angle. Angle of attack and side slip are obtained through a 5 port probe. Also on the board are a static pressure transducer, real time clock, and an ATmega168 that interfaces to a Castle Creations ESC to read motor RPM. All of the Navio data and additional sensor data is written to a log file when the gear switch is activated (so I can collect data on demand and not sort though thousands of data points). Data is post processed after the flight in MATLAB.


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Lars,

That is impressive! Please write more about your project, that it very interesting. What is PIW-VIW?

PIW-VIW method is one of the classical methods used to determine aircraft power required. It stands for power normalized to weight and velocity normalized to weight. Power, velocity, and weight at the test conditions are normalized to standard conditions so that a single curve can be generated that is good for all weights and atmospheric conditions. This method involves selecting various altitudes and airspeeds at which engine data is collected to back out the current power output. Since the method is applied at steady state conditions, power output is equal to power loss due to drag. Doing this for a number of airspeeds and altitudes allows you to generate that single curve. This is a rather lengthy process as truly steady state conditions are required for good data. The idea behind my research is to utilize accelerated flight to back out the instantaneous power required at all velocities in a single pass. Since steady state conditions no longer exist, the PIW-VIW method is not directly applicable but by knowing the aircraft states (this is where the Navio comes into play), the instantaneous drag can be determined through the equations of motion. This can then be used to determine the instantaneous power required. I’m still working on refining the method and all of the details haven’t been worked out yet, but this is the idea behind my research.

my rover setup…

not yet operational but getting there…

Questions:

  1. how can I set up the Gimbal functions in apm:rover APMplanner to use the proper servos?
  2. the crawler can also steer on the back axle… would like to configure that but seems I can only use channel 3 for steering?

and the gimbal closeup with picam on top…

my lack of experience with APMplanner takes some time now … :wink:

hugo

My rover is similar to yours…

I’m using 4G to control it and for the live Video stream (GStream). Works very well…

Hugo,
I just noticed something, you should think about swapping the pan and tilt axis of your camera gimbal. You have mounted it as tilt/pan. It is a little hard to discribe, but I try:
Imagine you have the camera looking forward,
now you look up 45°. Everything is fine. But, if you now begin to look sideways, your camera will start to look down. If you pan 90° left or right, all tilt will be gone and your camera will be looking at the horizon again. Over 90° left or right and it starts looking down. Just try it and you will see the problem.

ok that’s a cool rover! 4G cool I am still experimenting with wifi will have no reach.

ok gstreamer is ok over 4G at what quality?
and what latency on the live vid do you get?

some more pics would be nice …
do you have rear axle steering? if yes how did you hook that up in the navio?

great rig…

hugo