It's alive again!

 

I found some replacement screws for the one I lost in a local DIY store :). This afternoon I've also done some test flying to see that everything is OK and it seems so.

Regarding the package of replacement stuff and battery I ordered, it arrived in Sweden this morning but haven't got any updates from package trackers since 4.53 this AM. Hopefully I'll get it tomorrow but my hopes aren't that high for that to happened. Tuesday would however be a more realistic time of arrival.

Next I'll do some more trimming on the AltHold and will also try the AutoLand function soonish :).

Stay tuned!

Order for spare parts

I decided to order another frame as spare part to replace the lost screw and to have more parts in case, or when things break.

While ordering the spare frame, I also threw in a chargeable battery for the transmitter. The transmitter uses eight batteries and replacing that will be somewhat costly in the long run. The battery might need some modification to the connector to fit my transmitter but I don't think it'll be an issue.

Today I received the tracking number, and as I ordered from the Germany warehouse, I hope the shipment will arrive soon.

One motor down..

Yesterday, I started trimming the AltHold function that relies on any altitude sensors. The sensor I have so far been using is the barometer, which is very noisy. That means it's less then perfect at holding it's altitude, but works +/- 1-2 meters.

Today, I thought of doing some more testing, maybe even try the AutoLand function as the AltHold seemed to work. However, after a few minutes of flying this happened..

 

One of the motors came off upon takeoff and took a piece of the radio antenna with it. The motors are fastened with two screws at the bottom and it seems as it came unscrewed, possibly due to vibrations. This seem to be the case for one other of the motors when I checked them all. It seems as checking the screws before going flying is a bullet on the pre-flight checklist.

Now, I only found one of the screws, which means, I have to get another somehow. Not sure if I should order a whole new frame as spare part or if I should try to find one in a local utility store. I'm going to try the second option tomorrow to see if they have any thing available that would work as a substitute.

Yes, there will be more videos. I have two that I filmed yesterday when doing some trimming but I haven't uploaded them to YouTube yet as my bandwidth is limited and the amount is not unlimited at the moment.

Update on the lost signal alarm

In short, don't use the throttle servo as I did. Apparently it doesn't move enough during flight so the alarm behaves as if the signal is lost from time to time. I'm now using something else, channel 4, whatever that is, but it works fine. Channel 3 is throttle.

Sensors, sensors

 

This is how I've mounted the ultrasonic range finder. It needs to be mounted some distance away from other electronics to avoid interference. I still don't know if this will work but it's a first try. Otherwise I'll have to find another solution. The range finder has a maximum range of five meters and should be pretty exact. I still have no clue how the flight controller will treat it's information in conjunction with it's on-board barometer. That's for the future to tell.

The other sensor, or should I say alarm, is a lost signal alarm. It reacts by emitting beeps after one minute of no change to the servo I've attached it to. It's currently attached to the throttle and so, if I don't change the throttle for one minute, it'll start beeping. I'd say the theory is that if you don't move the stick for more then a minute, your signal should probably be lost. Anyhow, then after another minute, it'll sound a more than 85dB beep until it's regained signal. In theory you should then be able to find your model if it's crashed somewhere out of sight. Cheap insurance policy.

It has taken to the skies

 

[spot the shadow from the quad down to the right]

 

After painstakingly tuning P, I and D parameters in Mission Planner, it can now fly. This is a configuration part that I wasn't aware of until a few days ago, when I didn't understand why it was way too wobbly and always crashed. The reason was that my PID parameters was offside given the model, motor and propeller size I have. After some tuning using this guide, I was able to get it stable. There is still far to go when it comes to more autonomous flight but.. it flies!

Link to PID tuning guide.

Six weeks later

 

Six weeks ago, I ordered these items from Deal Extreme. Two weeks ago, I reported the package as lost and wanted an investigation into the possibility to get another package sent. However, the support department asked me to wait another week and here it is, the post office has done it's magic. Just wondering why some packages from China / Hong Kong arrive after nine days and some after six weeks. 

Anyway, to the right, a bluetooth to attach to the flight controller, which enables configuration and remote command both from a computer or smartphone. The Android app SteadiDrone enables remote control and the regular APM Mission Planner also allows for connection over bluetooth. The other thing is a USBISP thing that soldered to the Turnigy transmitter allows for firmware update. More on that in another post.