Solar-Powered Tello: Endless Flights Possible?

Thailand_Tello_Ken · Apr 30, 2020

Hi Everyone.

Have you seen these cheap lightweight solar panels on ebay?

I think it's possible to fuel the tello with a solar panel superglued on top of a full protecting lightweight propeller cage (also sold on ebay) with the (-) and (+) wires soldered to the leads that connect the motherboard to the battery section.

If we do the math, we can figure out the voltage and wattage required and then figure out how much such a solar cell would weight.
I doubt the weight of a solar cell + wires would exceed the weight of the tello battery fitted with a RunCam 2 action camera. I've seen a youtube of the tello flying with the weight of both.

Links: Full TELLO cage: HERE
Example of Solar Cell: HERE

I JUST bought my Tello. Watch my video . I don't want to experiment. If you try this on your drone and are successful, then all of us can do the same to ours. This would be REVOLUTIONARY! Imagine our threat being the innovator of an age of battery-less DJI/Ryze Drones!

volate!lo · Apr 30, 2020

Some number crunching fun...

Tello battery has 4.35v nominal voltage and 1100mAh, or 4,8 Wh. Tello flies 12min. So 4.8Wh are consumed in 12min. Tello consumes ~20 Watt. Actually its a bit less but thats not important as you will see

Tello's body is about 4x8 cm, or 0.0032 sqm and weights about 80gr and can carry 40gr (but then it consumes maybe 30-40W but we'll ignore this for now as well because again its not important).

A commercially available solar panel that can produce 20w is about 0,15sqm at a weight of about 2.000 gr.

Bottom line: you just need to shrink the panel by 98% and reduce its weight by 99% to make this work.

But there is more ...
Sun energy is about 1000 W/sqm at a perfect day around noon. Tello receives solar energy of 0.0032 sqm * 1000 w/sqm = 3.2 W. That is with perfect technology that converts sun into electricity at 100% efficiency, and the sun shining straight from above on a perfect day.
Best commercially available solar wavers have an efficiency of about 30%. So best output you could expect with current technology is about 1W (theoretically, in reality it's less than half of that).

Even with non-existing loss-less nano-weight conversion technology you'd still need around 6x more energy than the sun provides.

Dan · Apr 30, 2020

Concept is solid. We are testing micro-drones for payloads. We fly the Tello with 3D printed landing legs, and with an egg tosser. WE are also fling the Tello with a Halocode for light effects.Also testing the Mavic Mini. with a release mechanism. there is a video on youtube of some that placed a second tine LiPo battery of top of the Tello. The Tello does need a longer battery life, so keep working on it.. Also terered systems are being used to supply longer flight times. most drones could use longer flight times.

tellocuco · Apr 30, 2020

volate!lo said:
Some number crunching fun...

Tello battery has 4.35v nominal voltage and 1100mAh, or 4,8 Wh. Tello flies 12min. So 4.8Wh are consumed in 12min. Tello consumes ~20 Watt. Actually its a bit less but thats not important as you will see

Tello's body is about 4x8 cm, or 0.0032 sqm and weights about 80gr and can carry 40gr (but then it consumes maybe 30-40W but we'll ignore this for now).

A commercially available solar panel that can produce 20w is about 0,15sqm at a weight of about 2.000 gr.

Bottom line: you just need to shring the panel by 98% and reduce its weight by 99% to make this work.

But there is more ...
Sun energy is about 1000 W/sqm at a perfect day around noon. Tello receives free energy of 0.0032 sqm * 1000 w/sqm = 3.2 W. That is with perfect technology that converts sun into electricity at 100% efficiency.
Best commercially available solar wavers have an efficiency of about 30%. So best you could ever expect with current technology is about 1W.

So even with non-existing lossless conversion technology that does not weight anything at all you'd need around 6x more energy than the sun provides.

Thanks, I was pretty sure it would work like that but I was unable (the truth is: Lazy) to put numbers on it.

I believe OP has seen the Solar Impulse or those race car powered by solar energy wich is great but it recquire much less power to sustain the effort as it glides or drive.
Keep looking for new things and develop your creativity, it's great.

Cheers

SleepyRobo · May 7, 2020

Dan said:
Concept is solid. We are testing micro-drones for payloads. We fly the Tello with 3D printed landing legs, and with an egg tosser. WE are also fling the Tello with a Halocode for light effects.Also testing the Mavic Mini. with a release mechanism. there is a video on youtube of some that placed a second tine LiPo battery of top of the Tello. The Tello does need a longer battery life, so keep working on it.. Also terered systems are being used to supply longer flight times. most drones could use longer flight times.

A tethered tello with power from ground. Now that sounds like a super awesome project. With my 3gram cooling mod to motors how would we supply enough power up to the drone over a wire. It would have to weigh less than 37grams. I don't know any wire that small that could provide 4.2v say 60ft away with 40watt current. Unless you use a fixed boost converter to increase voltage and amps to the drone.

OH OH I GOT IT! How about just deleting the battery all together from tello that would save the necessary weight. A base station and a booster in battery bay would work right?

Delta0Glider · May 7, 2020

SleepyRobo said:
A tethered tello with power from ground. Now that sounds like a super awesome project. With my 3gram cooling mod to motors how would we supply enough power up to the drone over a wire. It would have to weigh less than 37grams. I don't know any wire that small that could provide 4.2v say 60ft away with 40watt current. Unless you use a fixed boost converter to increase voltage and amps to the drone.

OH OH I GOT IT! How about just deleting the battery all together from tello that would save the necessary weight. A base station and a booster in battery bay would work right?

If you're looking to thether it, I think you could mod something to fit into the battery pins in the bay so that it thinks it's the battery. Maybe sacrificing a battery for the shell, just be careful with the LiPos. Since I'm not sure USB would have enough power for it. If you're looking for something remote , well...microwave is probably out of the question due to the risk of frying the drone, not to mention interference.. It's a pitty we can't turn it on during charging, we could definitely try some tricks. Maybe even extending the flight time by having it carry a powerbank

. Speaking of...has anyone tried modding it to use classic rc li-pos? There are some bigger drones that achieve +30 mins by lugging bigger li-pos around. And the tellom while small, already has an insanse flight time for the weight.

SleepyRobo · May 7, 2020

Delta0Glider said:
If you're looking to thether it, I think you could mod something to fit into the battery pins in the bay so that it thinks it's the battery. Maybe sacrificing a battery for the shell, just be careful with the LiPos. Since I'm not sure USB would have enough power for it. If you're looking for something remote , well...microwave is probably out of the question due to the risk of frying the drone, not to mention interference.. It's a pitty we can't turn it on during charging, we could definitely try some tricks. Maybe even extending the flight time by having it carry a powerbank

. Speaking of...has anyone tried modding it to use classic rc li-pos? There are some bigger drones that achieve +30 mins by lugging bigger li-pos around. And the tellom while small, already has an insanse flight time for the weight.

Bigger battery may achieve more flight but increased torque on motors may have shorter flight times. Tello uses HV batteries "lipos" so you'd need a HV li-po and a 1s to fit in the frame might jot be possible.