Arducopter 2.0.42

Trnquill September 17, 2011 at 7:38am

I just can't get the alt hold to work. Previous software (2.0.3x, can't remember accurately the version number) did OK after some major tuning. I had the P value at 0, I value quite high and some D also, if I remember it correctly. My quad is quite big, weighting around 3,1 kg. It's about 80cm motor to motor across the frame. I have DualSky XM4240 850Kv motors and 12x4.7 props. I have APM buried deep inside my wooden frame, somewhat shielded from the turbulence, I guess.

The 2.0.42 has no D value in alt hold so I am not able to use the settings I previously had. First I tried with the stock settings but all I got was very heavy pulsating of RPM and virtually no altitude hold. After this I started to tinger with the parameters but in avail. No matter what I try the quad will not hold its altitude even within 10 meters. I have tried P values from 0 to 3, I values from 0,01 to 3, IMAX values from 100 to 600. Lowering the P makes things worse so that the RPM does not rise even if the quad sinks quite fast. Increasing the P only makes the motors pulsate harder and harder but the altitude does not hold.

After trying for about 8 batteries my quad finally flipped very close to the ground after fast descend and I broke three props. No more flying today. :/

James Roney September 16, 2011 at 10:32pm

Morning,

Second test flight, swapped out my 12x4.5's for 10x4.5's. Total thrust from 7kg to 4kg-ish. Tuned down PID's for rate by .5. Stable as ever. Got the balls to test sonar alt_hold(This did not work well for me once, hit alt_hold, copter dropped, I panic'd, flip back to stabilize, throttle was on full so it rised up like there was a rocket strapped to it, long story short, the tree won.) Held altitude better than I can and I am a veteren rc heli pilot. Yaw is ok, but moment of inertia seems a little high. You can really here the pitch of the motors change even to turn just a little. Will continue testing today. My personal roadmap that needs to be completed by Monday afternoon is.

1. Flying in stabilize (Must be as solid as a rock) - Completed

2. Test Alt_hold (Must hold within reason) - Completed

3. Test Loiter (Must hold within reason)

4. First simple mission (Take off, loiter, Land)

5. Actual Mission (Take off, Loiter 30s, move over to waypoint min dist 20M (Need to somehow tell it to do the moving at no more than 4km/h, thats walking speed), loiter 30s, land)

I lost my quad side telemetry, think I destroyed the regulator on the breakout board. Have ordered another. I almost feel like I am flying blind without it. Is there a way to use the tlog which you download to view everything that happened in APM by seeing the log in action like you normally would with the telemetry log by pressing play? I see I can convert the tlog to KML, which helps a bit, but the altitude is always underground, that part doesn't help much and you cannot change first person altitude attribs which sucks a little.

Thoughts so far, 2.0.43(When it magically appears, thanks to dev team) need not say Beta anymore.

Regards,

Solo.

Vincent Mees September 16, 2011 at 12:24pm

Finally got the time and the weather to load up v42 and have to say its a big improvement!!

And I left everything default. Surpised be this because previous version Ialways had to twinker with stable P or D

Stable is stable like previous versions. Very good.

AH great at low and high alt.

Loiter seems great though needs some finetuning when there is some wind.

Tested RTL several times and the quad just comes back very easy. But altitude goes up and down. As AH pids are great, which should I change to adress the oscillating alt in RTL???

And the finally a mission. My first. Started of with 3 WP. WP 1 was just a waypoint, WP 2 loiter for 10 sec and WP 3 LAND. I took off switched to auto and of it went :-) What a great feeling.

But .... It seemed that the quad did everything I wanted but only at WP1??? So it went to WP1, stayed there for about 15sec and started to descend very slowly until it touched the ground.

I then reloaded the mission and tried again. But nogo. Samething and I had the impression that the quad was very unstable.

I'm doing something wrong??

What I also noticed on the planner is that the current altitude isen't correct. It also jumps up and down. I for example start at 0m and land after a flight with -8m?

A great leap forward.Thanks guys!!!!!!!!

CyberCrash September 16, 2011 at 10:27am

Hey guys,

one question:

I tried to update to 2.0.42 via mission planer. But it just offered me 2.0.40 beta.

Is v42 still beta?

James Roney September 16, 2011 at 5:44am

Morning,

Flew my V2 this morning running 2.0.42. Used default PID's. Not bad at all considering I havent tuned it at all. X Quad. 7KG Thrust. Flying weight 2.5KG. Running Turnigy G10's with 12x4.5 props. 1m between motors. Will test Sonar etc once I have prooved my homemade airframe.

Regards,

Solo.

Jeff E September 16, 2011 at 2:51am

Jason I finally got it, it does work needed to change one more. having the LOW_VOLTAGE parameters makes it more accurate and will be able to tune when we want to trigger low_batt event.

This might not be for everyone but it would be a nice start to use the LEDS output. I hope you guys can consider but for those who wanted have the LED indicator here is the codes.

LED OFF (Motor disarmed)

LED ON (not blinking when motor armed)

LED BLINKING (when low batt event)

LEDs.pde on this post

Paramaters.h

(ADD)

k_param_low_voltage,

AP_Float low_voltage;

low_voltage (LOW_VOLTAGE, k_param_low_voltage, PSTR("LOW_VOLT")),

sensors.pde

(CHANGE)

from

#if BATTERY_EVENT == 1
if(battery_voltage < LOW_VOLTAGE)
low_battery_event();

to

#if BATTERY_EVENT == 1
if(battery_voltage < g.low_voltage)
low_battery_event();

Here is the video (Note: what I changed on the parameters (mission planner) is LOW_VOLT from 9.6 default to 13 just to test)

LED DEMO

DISCLAIMER:

- I only had 3 flights so far with this code and no adverse effect so far

- minor adjust is to return the low_batt to "false" in current code need to remove battery to return it

Martin Szymanski September 15, 2011 at 8:06pm

Tested 42 using sonar and barometer with Alt hold in simple mode.

Next is to use waypoints and auto mode.

The copter is a very fun machine with the latest code.

at 3:45 there is a swing it found :-)

https://www.youtube.com/watch?v=ao3k0Ydhcyw&feature=player_profi...

Lee Williams September 15, 2011 at 1:54pm

Hi Jason, had another test with 42 today, I upped the P in NAV WP up to as you suggested in my other thread, but it was moving around even worse, even though there was very little wind today, I believe the expression is "toilet bowling", nothing scary but taking up quite a bit of sky, alt was fairly good but again moved up and down quite a lot, but still this is the best performance in loiter mode I have had. I don't know what to do with regards to PID's now with regards to what ones to alter, eg Loiter PID's, NAV WP PID's etc, could you give me some advice as to what to try, I have included a google earth image of my track while in loiter and my log, thanks in advance Lee