Okay, so I'm trying to place my XY thermopile on a delta wing but have issues because of the vertical stabilizers. I don't get a clear view about 15-20 degrees off center of the two rear sensors towards the middle of the plane. Is this going to be a big deal?

If it is, I was considering putting winglets out on the tips of the plane and putting the sensor about halfway between the center of the plane and then tip to avoid what I can of the winglet. Again, at the center of the plane up front, the winglets would still be in the way of the sensor.

And one more question. If the XY sensor is place directly on the wing, will that be an issue at all for it? I ask because I know when I had it on an EasyStar, it will on the canopy where it had a pretty clear view of everything whereas on a wing, it'll have a pretty good view but it won't up off the wing much at all.

Yes, I know this is older technology but it's my way of playing around with an autopilot until I can afford an APM. I'll make due until then!

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I am working with an Ardupilot and thermopiles right now, on and Easy Star. It is pretty important the thermopiles have a clear line of sight "to the horizon" in order to work properly.


I think as long as you have clear line of sight directly in front of the sensor, you are ok. I don't believe they "view" a wide area. I could be wrong though.


Your last sentence , I could put in a post for myself. I got a really great deal on all the electronics so I can  get experience with the ardupilot before buying a APM/IMU.

It doesn't need a clear view. Just mount it on top of the cockpit and you'll be fine.
This place is great! I love all the help I get here. Thanks for the quick responses Ron and Chris.

Chris, you mean it doesn't need a totally clear view? A winglet directly in  line with the thermopile and the horizon might cause some problems, no?


Do you know if there has been any work to hack the thermopile to get a "visual" image of what it sees?

Thermopiles lenses have a view field of about 90 degrees. A little rudder end-on in the field of view is no big deal.
Ok, thanks, Chris.

Ahhh! Okay, so I have an issue now. I previously installed all the gear on an EasyStar and it worked wonderfully but now that it's on a delta wing, I'm having a little issue. I have the XY sensor placed up front with a pretty good view and the Z sensor is in a hole in the wing with a view of the ground and sky. The cable for the XY sensor comes out the front so I have the XY_SENSOR_LOCATION set to 0 and my ENABLE_Z_SENSOR is set to 1. My question is is there an up/down for the Z sensor (please say no!)? Also, the Z sensor does not protrude out the bottom of the wing. I have it currently mounted so the bottom of the Z sensor is about 1 cm higher than the bottom of the wing so it is far from flush but can see the ground. I did it to protect the sensor when belly landing.

I ask these qeustions because I got everything connected up and when I put my hand in front of the XY sensor in stabilize mode, the elevons go down and when at the back two sensors, the elevons go up, which is backwards from what I would need. When my hand is put to the right of the sensor simulating the right wing pointed to the ground, the left elevon goes up and the right goes down as it should and vice versa. I suppose I could set the XY_SENSOR_LOCATION to 2 or 3 to see if that would give me what I need but I shouldn't have to do that. Any ideas what could be wrong? I attached the config file so you can take a look.

Any help would be great as tomorrow will be another dead calm day before the snow settles in for the weekend. Thanks!



Again, all this is in the manual:


#define MIXING_MODE 0 //Servo mixing mode 0 = Normal, 1 = Elevons (or v tail)

#define REVERSE_ROLL 1 // To reverse roll, PUT -1 to reverse it
#define REVERSE_PITCH 1 // To reverse pitch, PUT -1 to reverse it
#define REVERSE_RUDDER 1 // To reverse rudder for 4 channel control setups

#define REVERSE_ELEVONS 1 // Use 1 for regular, -1 if you need to reverse roll direction
#define REVERSE_CH1_ELEVON -1 // To reverse channel 1 elevon servo, PUT -1 to reverse it
#define REVERSE_CH2_ELEVON 1 // To reverse channel 2 elevon servo, PUT -1 to reverse it

I saw that and thought I had made the appropriate changes. This does bring up a couple more questions.

It says

// NOTE - IF USING ELEVONS, 1-2 and 1-3 should be 1.

I've seen that notation in the manual and code in a few places but what exactly are 1-2 and 1-3 referencing? In this case, is it REVERS_PITCH and REVERSE_RUDDER? That has confused me before.

Also, now that I think about this more, these settings for reversing roll and pitch in the code apply when NOT in manual mode correct? I remember you saying that in manual mode, the signal from the receiver comes right through so I assume none of these settings will have an effect in manual mode regardless of how they are set.

Now, I do remember changing REVERSE_PITCH to -1 but I may have possibly set XY_SENSOR_LOCATION to 1 at the same time, which would have effectively negated it. I'll have to try tomorrow. Approaching midnight here! I tried a few things and nothing seemed to work so I'll have to play with it again tomorrow.

Thanks for putting up with me Chris. I hope to be able to contribute somehow once I get this down!

Those refer to section numbers. (It's a bit unclear). They only affect non-manual settings.
In this case then, what code does 1-2 and 1-3 refer to? Thanks.

The IR sensors have about a 60° field of view. Anything less is OK for stabilization. But limits your ability to maintain accuracy at steeper bank angles.


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