Helipad on car hood?

[dirkclod]

Then how do you explain me taking off from a steal bed directly over the gear case .
Here I had been out flying and decided to do a rth with precision landing. Landed right where I took off.

 

[bonzo]

Then how do you explain me taking off from a steal bed directly over the gear case .
Here I had been out flying and decided to do a rth with precision landing. Landed right where I took off.

Man, I miss that Go 4 interface

 

[sar104]

Then how do you explain me taking off from a steal bed directly over the gear case .
Here I had been out flying and decided to do a rth with precision landing. Landed right where I took off.

The answer is probably that your truck bed, while steel, has not become magnetized. If you are following the recommended check that the aircraft heading is correct before takeoff, and it is, then that confirms that it is not interfering with the compass.

 

[dirkclod]

The answer is probably that your truck bed, while steel, has not become magnetized. If are following the recommended check that the aircraft heading is correct before takeoff, and it is, then that confirms that it is not interfering with the compass.

Must be spot on as usual sar but I still glow in the dark

 

[slup]

Must be spot on as usual sar but I still glow in the dark

Well ... all this could have a simple explanation & perhaps this haven't anything to do with if your steel bed is magnetized or not.

All wrongly worries about the take-off spot when they actually should worry about the power-on spot ... the IMU initializes to the compass direction shortly after that the craft is powered on, not when taking off.

So, don't know but ... did you power on your craft elsewhere than on that steel bed, perhaps you held it in your hand outside the bed & then sometime later put it there for take-off? If so ... that probably saved you from a yaw error.

 

[GrayHornet]

I'm wondering if I can apply a colored Helipad vinyl sticker onto my black tonneau tri-pad cover? It would give me a brighter landing target. I googled for such a product but did not find any unless you custom design one.

 

[brewc]

I routinely take off from the hood of my Jeep and will hand land as the obstacle avoidance prevents from landing, as I think the windshield is the issue in the sensors.

 

[terradriller]

Agree, not have the S2 but with my M1 and 2 my 1990 truck bed was my
pad. All steel .Never any issues. Would set it right over where the 5th wheel
ball hole was over the rear end. Now I got a 2011 ford with a aluminum body and now way. Ya don’t know till you try it.
‎

Great job on the video..especially like the cell tower...no way I could do that job

 

[dirkclod]

Great job on the video..especially like the cell tower...no way I could do that job

Me ether

 

[Tucson_Guy]

What is the best method of determining potential compass errors before taking off? Is the icon on the map the only indicator of which way the drone believes it is pointing?

Perhaps if I orient my pad so that it is always in a cardinally correct position, and place the drone atop it accordingly every time (ie: north facing) then I should be able expect the icon to always be pointing to the top of my screen on the map below if the drone is always sitting facing northward.

I made my own lightweight but rigid pad, complete with LED lighting. I guess a built in compass would be cool. Whether the pad compass will read correctly because of the potential interference kind of leads us back full circle lol.

Now I am itching to add a digital compass to the pad just because. I see an amazon search in my immediate future.

If a magnet sticks to your hood it may cause compass errors. If not you're good to go.

 

[julius13]

I’ve been flying DJI drones for almost 6 years now. In the beginning I always searched a good clean launch site. I fly a lot of construction sites so dust and dirt are a common issue. I made my own launch pad in the beginning but I only used it twice. So against a lot of peoples advice I launch and land from the roof of my car 90% of the time. I do have a glass roof but still a car is a big hunk of metal. However, I’ve never had an issue with the drone responding. Generally I will hand catch my Phantom 4 pros when landing but talk off from the hood. Personal preference I suppose.

 

[slup]

...So against a lot of peoples advice I launch and land from the roof of my car 90% of the time. I do have a glass roof but still a car is a big hunk of metal. However, I’ve never had an issue with the drone responding.

And in here lies your misunderstanding about when a yaw error is created ... it's neither at take-off or landing, instead it's when the craft is powered on.

At power on the IMU yaw will align with the compass direction ... it will be initialized by the compass. If this happens away from magnetic disturbance the compass isn't deflected & the IMU will be initialized into the true direction ... if you then later carry your craft & place it in magnetic disturbance the compass will be deflected but not the IMU. And it's the IMU yaw that matters as it's that information the flight controller primarily use in order to navigate.

The compass ... & the gyro aren't completely out of the game after power on or later in the flight. If your craft ends up in a severely magnetic disturbed area during flight both the compass & the gyro will slowly feed in adjustments to the IMU. So being in disturbance too long can cause problems ... but this scenario is really rare, your craft usually isn't affected for very long if you for instance pass a steel bridge.

 

[Meta4]

And in here lies your misunderstanding about when a yaw error is created ... it's neither at take-off or landing, instead it's when the craft is powered on.

But it's uncommon for anyone to power on and then move their drone to a launch spot.
The launch point usually is the power on spot.

 

[dirkclod]

Well ... all this could have a simple explanation & perhaps this haven't anything to do with if your steel bed is magnetized or not.

All wrongly worries about the take-off spot when they actually should worry about the power-on spot ... the IMU initializes to the compass direction shortly after that the craft is powered on, not when taking off.

So, don't know but ... did you power on your craft elsewhere than on that steel bed, perhaps you held it in your hand outside the bed & then sometime later put it there for take-off? If so ... that probably saved you from a yaw error.

No I powered on in that spot and took off. Was just my normal procedure when I had that truck.

 

[dirkclod]

If a magnet sticks to your hood it may cause compass errors. If not you're good to go.

I keep a large magnet stuck to the inside of my truck bed with a rope to check creeks by bridges for things that may have been thrown in creeks Like sar said my bed may not be magnetized
but ..

 

[slup]

But it's uncommon for anyone to power on and then move their drone to a launch spot.
The launch point usually is the power on spot.

Yep ... especially if the power button is on the top side of the drone it's easy to have that habit. (Still uses my old trusty MA1 with the button on the belly so kind of forced to power on else where than on ground )

Never the less ...

-if having the correct understanding about when yaw errors occurs

-take on the habit to power on the drone as far away from suspicious magnetic surroundings as possible (in your hand midair)

-and check the IMU initialization result on the app map before take off

You most likely never will be forced to experience the consequence of a yaw error midair.

 

[julius13]

But it's uncommon for anyone to power on and then move their drone to a launch spot.
The launch point usually is the power on spot.

I have SUV that I open the hatch and use the back of car as workstation. I power up the drone, controller, and DJI Go app. When prompted to calibrate the drone I do so then place the drone on the roof of the car. Sometimes I allow RTH to see if the drone will land on the roof. Never failed me once.

I’m not advocating anybody else do this. I just know it works for me. I’m usually in tight areas with a lot of construction activity. Admittinglyi was nervous the 1st couple of time I launched this way but it’s now second nature.

 

[Meta4]

I have SUV that I open the hatch and use the back of car as workstation. I power up the drone, controller, and DJI Go app. When prompted to calibrate the drone I do so then place the drone on the roof of the car.

DJI's compass warning is badly worded and there is no need to recalibrate anything.
Those warnings are the compass advising of magnetic interference and telling you that launching there is not a good idea.
You may have been lucky in the past, but that doesn't mean you always will be.

 

[julius13]

DJI's compass warning is badly worded and there is no need to recalibrate anything.
Those warnings are the compass advising of magnetic interference and telling you that launching there is not a good idea.
You may have been lucky in the past, but that doesn't mean you always will be.

I agree it could. Likely happen. 300+ launch’s with no issues.

 

[teeroy]

Now I got a 2011 ford with a aluminum body and now way. Ya don’t know till you try it.
‎

I have a 2011 F 150, the body isn't aluminum. I have launched from the composite bed cover with my Mini 1 and it was fine, when I tried with the Mini 2 I did get a few compass warnings. Ford didn't start making the aluminum bodied trucks until 2015.