I would like to share with you an awesome news regarding the R&D of CarCopter droneCARCOPTER DRONE XERALL

This is quite big and important update.

Once I got back to designing the second version of CarCopter, I had questions rising in my head. is is the first attempt to make such a drone, so I had no data to support my thoughts.

My big concern was if the quadcopter can fly with movable arms, equipped with suspension ( shock absorber, swaybar etc). Most of the engineers and people from RC world, which I asked for an opinion, told me straight away, that it will not be able to fly at all, as it is impossible to tune PID or software in such a way it will take into consideration the stroke of the arm ( suspension), its inertia, spring tension etc.. Saying shortly the system dynamic will be really bad for the drone flying.CARCOPTER DRONE XERALL

So thought, the problem can be easily solved by, designing the shock absorbers that can lock before the drone takes off. I started designing such shock absorbers, but midway I discovered many issues with this idea. So I decided to build a rough prototype to find out myself if the drone will actually fly.

To my surprise, the drone flies very well ! the arms can freely move up or down ( but the force vector does not change its direction, as all propellers despite moving up and down stay parallel to each other). It actually looks very cool once the drone is airborne and you can see suspension working.

I also noticed that arms absorb vibrations from motors, propellers and the drone seems to be more stable than with regular stiff frame.

Another thing that got my attention is the fact, that drone became more resistant ( it does not have to constantly adjust its position ) to lateral gusts. I think this is because arms absorb the gust force before it has the impact on the drone itself. (like in the car on the ground, the suspension is smoothening out bumps and vibrations, the same seems to be happening in the air). This finding obviously has a positive impact on the video quality.

I believe the drone is also more resistant to crashes, as the shocks can absorb a lot of impact forces before it gets transferred to the frame. ( you can see heavy RC cars being dropped from 3-5m hights, wiht no dmamages) . I have not tested yet the drone, I just assume that.CARCOPTER DRONE XERALL

Apart from those findings, the most important for this project is the speed and ease of transition between drive and flight mode.

If I had to go down with the lockable shock absorbers idea, it would make the drone more complex, more expensive, heavier. The most important, the transition would be longer as the drone would have to stop, lock the arms and then take off, the same steps would be essential to the landing.

By having the suspension engaged all the time ( on the ground and in the air), makes things much simpler, cheaper etc. But the most important; it makes the fly/drive transition just awesome! As the drone will be able to literally droop down ( even from 1-2m height) straight on the wheels and drive.

Those finding + 16 cm in diameter wheels, 6 cm clearance !! 5.5 cm suspension stroke, the endurance of 12 min in the air, 20 min on the ground are really making the CarCopter idea really solid.

BTW: I will make a short video and share with you in next 2-3 days. SO stay around to see something very unique.


CarCopter Concept 1



While the X-TankCopter is being made. It is the the time to get back to work on the the CarCopter.

Just video remainder of the very first prototype.

This post highlights the first concept of the flying car, there are 3 other versions to be designed, all of them are quite different from each other.The objective is to create the best combination of air and ground performance. Therefore, I would be more than happy to hear your opinion. Hopefully that will help us to choose the best version.

The proposed concept is based on 5-inch propeller, so relatively small. The weight is about 930 grams.

You can see the size of it on A4 sheet.

The drone in the air:
Due to the revolution in drone race field, there are a plenty of motors to choose from, they capable of producing 650 g of thrust from 3 s battery and over 1700 g from 4 s (5-inch propeller). So, there is an easy way to upgrade (double) the air performance, going crazy we can even use coaxial setup (two Contra-rotating propellers in the wheel), but definitely there is no need. The presented model is based on 3 s (11.1 V) 5000 mAh battery, the expected hover time is about 13-15 min. The thrust to power ratio is about 2.7:1. The on-board camera will probably be RunCam Split as it is only of its kind. It provides amazing recording video quality (60 fps 1080p) while streaming low latency live video (FPV). The Flight Controller, CleanFlight, BetaFligt or similar. Frame materials: carbon fibre and duraluminium, Nylon or ABS-PC wheels housing, POM gears.

The drone/car on the ground:
Equipped with huge wheels (16 cm in diameter !), will provide a good performance in rough terrain. Drone should be able to cross obstacles that would be a problem for most of the RC cars. Suspension, with a good clearance of 40-50 mm. Ackerman Steering System, rear wheel drive and differential. Powered by 400-500 W motor.

Here is an interesting part. The question raises: how the suspension will affect the stability of the drone in the air? Since propellers are suspended on moveable arms.
The thrust vector does not change the direction, as all propellers stay parallel to each other and perpendicular to the frame. The only change is the temporary force magnitude applied to the main frame ( due to the momentum of the suspended arm).

In theory, tunning the PID and choosing the right compression of the shock absorbers should solve the problem. The drone may lose a bit of its agility but it should still fly well.
Also, the drone may be less sensitive to lateral gusts, as the arm can move up or down and compensate for a momentary gust (similar to driving on the ground).

This is the only theory, real-life testing is essential in order to gather the data. But I would love to hear your thoughts.

Stay around to see more development post, you can follow the new post or comment by ticking the check-boxes at the bottom of the page.

If among your friends you have, engineers, hobbyists or new tech lovers, please share this post with them. The more feedback at the R&D stage, the better the drone will be. I am sure they will find it interesting, in the end, we’re building a flying car here.

kind regards