Technical specifications

[Lokesh]

Q.1 Which processor does the FC have? Please provide details.

Q.2 What is the diameter and pitch of the propellers that come with the kit? (Of course I’ve measured dia with scale and it comes around 2 inches but need exact figures)

Q.3 What is with load RPM of the motors and also what is voltage rating of the motors?

[Lokesh]

Sorry the first part of Q.3 is irrelevant. Please give me size and KV rating of the motors

[prasanna.shevare]

Hey Lokesh,
Q.1 Which processor does the FC have? Please provide details.
Ans. There are two FCs which drona has: PrimusV3R has an STM32f103 and PrimusX has STM32f303

Q.2 What is the diameter and pitch of the propellers that come with the kit? (Of course I’ve measured dia with scale and it comes around 2 inches but need exact figures)
Ans. The propeller used are very small. In general, such propellers dont come with measurement of pitch. We have estimated the pitch using measurements. Again we have two versions here. PlutoV3R has a 2.16in x 1in. PlutoX has 3in x .6in

Q.3 Please give me size and KV rating of the motors and also what is voltage rating of the motors?
In DC brushed motor, the motor specs are in general not provided in kV but rather in no-load speed. PlutoV3R has a 7mm DC brushed motor with NL speed of 50000RPM @ 3.7V. In plutoX, the motor size is 8.5mm and the NL speed is confidential.

[prasanna.shevare]

If you are pursuing a project, let us know about your project, we would like to help if we can.

[Lokesh]

What I understand by Kv is its the RPM per volt so we can calculate by the formula -> max RPM = Kv * supply voltage. So if motors are rated at 3.7V and have max RPM of 50000 isn’t that Kv comes out to be 13513? (as per this data inverse law of motors holds good)

[prasanna.shevare]

This is good for a ballpark estimate. The accurate representation is RPM = kV * backEMF. Since at no load, the supply voltage and backEMF are closer, this is a decent estimate. According to our estimates, the kV rating is close to 14000. Our assumption is that this discrepancy is due to a higher resistance of brushed DC motor. Thus in general, no-load RPM is preferred by a manufacturer.

[Lokesh]

Also I would like to confirm if the propellers that comes with Pluto V3R have tip of type Hybrid Bull Nose

[prasanna.shevare]

PlutoV3R doesnt have a bullnose prop. We did our tests to realise that Bullnose props are much quieter but consume much higher current. If you want to switch, you can try those, but we expect a lower flight time.

[Lokesh]

Then which category the props fall in among Pointed, bull nose or hybrid bull nose?

[prasanna.shevare]

I believe it is pointy nose propeller.

[Author]

Posts