Help! Airspeed Indicator

[BlockerAviation]

Ever since I started flying fpv I've wanted a way to know my airspeed. Many of my fpv crashes have been on takeoffs and landings, all of them due to stalls on takeoff and landings or over speeding the airframe on landings. Although now I've gotten better with flying fpv I would still like to have an airspeed Indicator to make my landings and takeoffs more consistent. Inorder to do this thought up a design (which has probably been done before) where a coreless motor is placed on the aircraft where it will receive unobstructed airflow is then used as a generator, producing a proportional voltage to the airspeed at which the plane is flying. Then the voltage is sent to some sort of programmable board (probably an Arduino) and is turned into a value that corresponds to the airspeed of the plane. This is then relayed to a display to show my airspeed when I'm flying fpv. I have a few questions though,

Could this work?

How expensive would it be to make?

Is there an easier/cheaper way?

Could I make it small enough to go on my Dragonfly MkII/MKIII

I've also seen where @Fallegon made a variometer for a glider that can be seen through an fpv camera. Anyways I hope my rambling has made sense, and let me know what you think, should I embark on this endeavour if so any tips on what to do or get to make this possible?

 

[flyingkelpie]

I would make something like this

using just a fan which measures the speed and then use an arduino to set it up. Just make it compatible for the plane. Unlike the photo.

 

[BlockerAviation]

I would make something like this
View attachment 189510
using just a fan which measures the speed and then use an arduino to set it up. Just make it compatible for the plane. Unlike the photo.

Thats the plan, my problem is getting that into my dragonfly MKIII. Maby I could find a cheap one to take apart and use in my airplane. although, I like the versatility of the Arduino.

 

[flyingkelpie]

Thats the plan, my problem is getting that into my dragonfly MKIII. Maby I could find a cheap one to take apart and use in my airplane. although, I like the versatility of the Arduino.

That is what I thought but how to transmit the info to a display on the ground.

 

[quorneng]

Its called telemetry.

 

[flyingkelpie]

Its called telemetry.

How can you transmit the lcd to a ground lcd though?

 

[Ketchup]

How can you transmit the lcd to a ground lcd though?

I think spektrum already has this lol. You need to get a telemetry module and the pitot tube kit and it will send airspeed to your tx. There should be a way to connect that to the goggles.

 

[flyingkelpie]

How can you transmit the lcd to a ground lcd though?

I mean lcd to fpv. lol

 

[BlockerAviation]

That is what I thought but how to transmit the info to a display on the ground.

Don't need to, i just have to get it in view of the fpv camera.

 

[BlockerAviation]

I think spektrum already has this lol. You need to get a telemetry module and the pitot tube kit and it will send airspeed to your tx. There should be a way to connect that to the goggles.

Spectrum does have an airspeed Indicator but to set it up is expensive and in order to use it with my radio I have to look at the radio when want to know my speed.

 

[mdcerdan]

You can make an old fashion airspeed indicator...

Just make the scale visible in front of your camera. It is just a plate facing the incoming wind and a spring. You can calibrate your scale with an anemometer or just driving in a car.

 

[CampRobber]

Real airplanes use pitot tubes, which are pressure sensors measuring differential between stagnation pressure and ambient pressure. You can buy RC pitot airspeed sensors for flight controllers and send it back to your radio without any DIY, really.

If you want to DIY it, you could fabricate the pitot yourself and buy the same microchip they're using from digikey... but pressure sensor chips are expensive and buying the actual pitot kit may not be much more $$.

I'm not aware of any airplane that uses anemometer-type airspeed sensors, but some do have emergency ram air turbines which look kinda similar, lol.

 

[BlockerAviation]

You can make an old fashion airspeed indicator...

View attachment 189523

Just make the scale visible in front of your camera. It is just a plate facing the incoming wind and a spring. You can calibrate your scale with an anemometer or just driving in a car.

That may work but trying to calibrate it and make it accurate and repeatable at this scale may be difficult. I'm estimating that the top speed of my airplane is only around 25mph and the stall speed is only about 8mph.

 

[BlockerAviation]

Real airplanes use pitot tubes, which are pressure sensors measuring differential between stagnation pressure and ambient pressure. You can buy RC pitot airspeed sensors for flight controllers and send it back to your radio without any DIY, really.

If you want to DIY it, you could fabricate the pitot yourself and buy the same microchip they're using from digikey... but pressure sensor chips are expensive and buying the actual pitot kit may not be much more $$.

I'm not aware of any airplane that uses anemometer-type airspeed sensors, but some do have emergency ram air turbines which look kinda similar, lol.

I thought about using a pitot kit but after all adding up all the equipment I'll have to get, I found it to be to expensive.

 

[mdcerdan]

That may work but trying to calibrate it and make it accurate and repeatable at this scale may be difficult. I'm estimating that the top speed of my airplane is only around 25mph and the stall speed is only about 8mph.

check this: https://www.thingiverse.com/thing:3198028

and this:

 

[BlockerAviation]

check this: https://www.thingiverse.com/thing:3198028

and this:

That's awesome! Although it might be hard to read on my smaller planes, I'll definitely use that on one of my bigger aircraft tho.

 

[flyingkelpie]

Don't need to, i just have to get it in view of the fpv camera.

Oh so will it be in the same view as the main camera or will it be different but as a side bar?

 

[BlockerAviation]

I was thinking more a setup similar to this https://forum.flitetest.com/index.php?threads/som-glider-thingy.59559/#post-497162 but displaying speed instead of sink and lift.

 

[Fallegon]

Sorry if I'm late to the party. I actually already have this set up and it just takes a bit of programming. They do sell stuff like this for whichever receiver your flying.. https://www.amazon.com/dp/B01J7NCML0/?tag=lstir-20

I had planned to make a video about the airspeed sensor but I can give you the components list if thatl get you started.

https://www.amazon.com/gp/product/B01M19EIF8/?tag=lstir-20
Sensor
https://www.amazon.com/gp/product/B07D9H83R4/?tag=lstir-20
and sum Oleds of your choice.
These can be run by an onboard arduino like how I had my variometer. I had set it up for a 8th scale p51 I haven't finished yet. Understand though that this way of doing things is not telemetry and can only be viewed form the onboard camera. I'm sure you could get into OSD and program the input to it but that would take a lot of work.

 

[BlockerAviation]

Sorry if I'm late to the party. I actually already have this set up and it just takes a bit of programming. They do sell stuff like this for whichever receiver your flying.. https://www.amazon.com/dp/B01J7NCML0/?tag=lstir-20

I had planned to make a video about the airspeed sensor but I can give you the components list if thatl get you started.

https://www.amazon.com/gp/product/B01M19EIF8/?tag=lstir-20
Sensor
https://www.amazon.com/gp/product/B07D9H83R4/?tag=lstir-20
and sum Oleds of your choice.
These can be run by an onboard arduino like how I had my variometer. I had set it up for a 8th scale p51 I haven't finished yet. Understand though that this way of doing things is not telemetry and can only be viewed form the onboard camera. I'm sure you could get into OSD and program the input to it but that would take a lot of work.

Thanks for the help! I think I'm going to go with the OLED approach because I don't really like the look of on screen displays and, because I think that using the OLED as an instrument panel will make the fpv experience feel more like flying a full scale aircraft. As for the sensor, I think I'm going to stick with the anemometer because of the price factor and weight.