Tilt and maximum flight speed

[talm0]

Does anyone have insight how the tilt value correlates to speed? I set the tilt_atti_range to 60, the maximum allowed. Interestingly, maintaining this tilt throughout a flight definitely does not result in maximum achievable velocity. In fact, it seems backing off on the throttle by about 20% seems to have the effect of increasing the aircraft speed. Initial acceleration may benefit from the greater tilt, but even that's hard to be certain about.

Would greatly appreciate if anyone can chime in with knowledge or observations of their own.

 

[Top Hat]

From my own experiences w/ MP it is fast enough for intended use of it.
If I need speed rather than flying camera, I'm gonna get me a racer drone for the purpose.

 

[talm0]

From my own experiences w/ MP it is fast enough for intended use of it.
If I need speed rather than flying camera, I'm gonna get me a racer drone for the purpose.

That's a great answer, DJI. Thank you for telling me how to use your drone properly. But, my question wasn't about that.

 

[CyberNate]

Does anyone have insight how the tilt value correlates to speed? I set the tilt_atti_range to 60, the maximum allowed. Interestingly, maintaining this tilt throughout a flight definitely does not result in maximum achievable velocity. In fact, it seems backing off on the throttle by about 20% seems to have the effect of increasing the aircraft speed. Initial acceleration may benefit from the greater tilt, but even that's hard to be certain about.

Would greatly appreciate if anyone can chime in with knowledge or observations of their own.

I noticed the same thing. I like the 60 degree tilt for fun in transitions, but the top speed is not maximized. Seems that the tilt is too aggressive and the Mavic over compensates when backing off the tilt to maintain altitude. The best thing you can do is trial and error on the max tilt setting to find the sweet spot for top speed. It would be awesome if you did this so I don't have to ;-). Also, it probably is different if extra batteries are attached due to the extra weight. I actually get better performance when I run with dual high c rating 1500s. There's more current available and less load on the main battery.

 

[mkp2020]

I've not tried it, but saw one video suggesting 33?

 

[CyberNate]

I've not tried it, but saw one video suggesting 33?

You're talking about Steve's videos. That setting is for GPS mode and is for a speed slightly less than 40mph. The stock tilt for sport mode is 35. Maximum speed should be somewhere around 55 degree tilt.

 

[mkp2020]

You're talking about Steve's videos. That setting is for GPS mode and is for a speed slightly less than 40mph. The stock tilt for sport mode is 35. Maximum speed should be somewhere around 55 degree tilt.

I see - thanks!

 

[dwallersv]

This is a simple physics problem, and a standard aerodymics scenario.

4 forces are balanced in flight: Gravity, lift, drag and thrust.

For a quad, lift and thrust are a simple trig problem. In summary, maximum speed will be achieved at the maximum pitch angle at full power that can maintain altitude.

 

[namja]

42. Isn't that the answer to ... everything?

Based on my limited experience, seems like 60 is too high also. It seems to back off a bit at max tilt. I think it flies faster and better at around 50. Plus, others have suggested to put the Sport tilt setting at 50, so take that into consideration as well.

 

[talm0]

This is a simple physics problem, and a standard aerodymics scenario.

4 forces are balanced in flight: Gravity, lift, drag and thrust.

For a quad, lift and thrust are a simple trig problem. In summary, maximum speed will be achieved at the maximum pitch angle at full power that can maintain altitude.

Nice, thank you. I then found this: http://www.dept.aoe.vt.edu/~lutze/AOE3104/thrustmodels.pdf
So, 60 seems too high to achieve maximum speed. 50 is suggested, but probably will still not yield maximum. So, then it's somewhere between 50 and 60. Can a physics/aerodynamics expert crunch some numbers? Many of us would be very grateful.

 

[GooniesNeverDie]

You're going to be limited by the speed of the motors. The tilt is only one component to start, stop and maintain. But I'm not a scientist. But this finding doesn't surprise me.

 

[talm0]

ld be awesome if you did this so I don't have to ;-)

Just a small update:
A tilt value of 55 seems to be the maximum needed to achieve the highest speed, but not in every situation. When flying against the wind [headwind], backing off approximately 10-20% results in a faster speed. At the same time, the aircraft tailwind benefits are amplified the most when the throttle is at maximum. With slight tailwind/headwind at about 260' AGL and doing the above I am able to achieve 34-36mph and 46-50mph respectively. If it's maximum speed you're after then no situation seems to warrant full throttle at all times, but the tilt value of 55 (+/- 1) seems to give the most consistent and best result.

 

[Strafe1]

My value of 50 yields a 46mph reading into a slight wind, and about 51mph with.

 

[Ron_Dog]

I also fly racing drones,and increasing the AOA (Angle of Attack). creates parasitic drag on the air frame. The point of best performance is (and it changes with conditions) is between 45-50 degrees. That's why some are finding by easing back on the right stick (lowering the AOA),results in a increase of speed,and penetration into the wind. Not only that,but the more drag you induce on the air frame,the more power is wasted,and flight times drop! Think of your drone as a knife blade cutting through the wind. Raising the profile of the blade,will hinder it cutting through the air/wind,as opposed to keeping it flat,and cutting through the air.

 

[VizualFly]

With configuring tilt and speed parameters discussed here, does anyone have any advice on braking parameters and the best numbers to use? Let's say with 45-50degree tilt. I would assume braking parameters should be considered.

 

[Ron_Dog]

With configuring tilt and speed parameters discussed here, does anyone have any advice on braking parameters and the best numbers to use? Let's say with 45-50degree tilt. I would assume braking parameters should be considered.

I have no experence with "braking parameters"! LOL! On the racing drones you fly mostly in "Rate Mode",so if you pitch forward,it keeps going forward,until you pull the right stick back (Brakes). I'm having a hard time getting used to the Mavic braking on it's own, if I let the stick go back to neutrual. LOL!

 

[VizualFly]

Thanks! Maybe I need to learn more with racing drones and complete the skillset!

 

[dwallersv]

I have no experence with "braking parameters"! LOL! On the racing drones you fly mostly in "Rate Mode",so if you pitch forward,it keeps going forward,until you pull the right stick back (Brakes). I'm having a hard time getting used to the Mavic braking on it's own, if I let the stick go back to neutrual. LOL!

Another reason to have the missing ATTI mode. People (myself included) have simulated this by covering the GPS antenna with foil, forcing ATTI mode. Flies just like a racing drone in this respect -- like an air-hockey puck. Actually, like any rotary-wing aircraft without a smart computer helping you fly it (taking over all the really tedious, hard skill flying, like hovering in place for example).

This too can be adjusted with a parameter change, so that one of the positions of the mode switch can be ATTI. Most people temporarily replace Sport, so GPS and ATTI modes can be flipped between.

 

[carleido]

Has anyone set the best configuration value?
50?
55?
60?

Thank you

 

[CyberNate]

50 works well.