Custom Power Train - TMotor P80, 80A ESC, 26", 12S


#1

New to PG and PPG, but planning on getting my cert coming Sept/Oct. I come from the drone industry (I design, fabricate, test a wide range of custom drone technologies) and looking to apply that to a custom power train for a PPG system.

Have done a decent amount of research at this point, though it seems relatively limited when it comes to electric, everyone runs gas (gross!) There are some single electric motor systems out there, but $$$$$$$. Then I came across the OpenPPG project and was instantly in love with the design and method.

I will probably design and fabricate my own carbon and accessories (looks like I wouldn’t be able to get an OpenPPG setup until Batch 4 anyways, whenever that would be?) Power train is where I’m looking for input. Sanity checks are good from experienced pilots. I don’t usually strap myself to my creations.

Currently spec’d it out based on a TMotor power train.

  1. Motor: P80 170kV http://store-en.tmotor.com/goods.php?id=424
  2. ESC: Alpha 80A HV http://store-en.tmotor.com/goods.php?id=584
  3. Prop: 26x7.8 2 blade (Would post a link but only allowed 2 as a new user :slight_smile: )
  4. Battery: Bonka 6S 22Ah (on OPPG website)

@12S2P it’d be pushing ~60kg thrust @ ~220A WOT. Compared to a similar spec’d gas setup (Black Hawk 100cc), which pushes ~55kg (I weigh about 170lbs after a trip to the bathroom).

@WOT (220A), the 44Ah lipo would give about 10 minutes flight time (considering 80% rule). I assume this only be required at launch or climbing, and would guess cruise would be about 50% throttle? This would give about 20kg thrust @40A. About 53 minutes of flight. Seems like most are getting closer to 25 minutes flight time, which between launch and climb and cruise, seems reasonable.

Black Hawk weighs about 22kg (before fuel I assume). The above setup, about 15kg (no harness, no frame). So on spec there.

This would run about $2600USD (I’m hoping I can get some discounts since I deal with TMotor, also a Canuck and the conversion will hurt at the moment), which is way cheaper than any RTF electric or gas setup. Add harness, frame, accessories, wing, shouldn’t require me to eat noodles for months.

Also planning on getting a wing I can PG or PPG with, not looking to do acro (yet!).

Thoughts?


#2

There’s a few things about this post that got my attention.

In the future I believe were going to be seeing people playing around with their battery voltages, motor kV and props to fine tune all the efficiency out of their system that they can.

I saw a Y.T a few months back where a couple of local Melbourne Drone Racers went to the T-Motor factory. In the video they indicated that T-motor were open to ideas / mods / further development of their products. My first thought was ‘custom props’. You know the quiet ones with winglets on the ends.
Then started dreaming of sine wave ESC’s with data logging - how useful would that be? Custom motor winds, battery config’s…Mmmm- Then I woke up

Anyway. You mentioned that you deal with T-motor. Show them this project. See what input they have. Would they be willing to supply custom parts for us to experiment with?

Also, max prop size for this frame is 22-23" yeah? guys…

Welcome to the discussion.

And here’s a link to the vid I was referencing; https://www.youtube.com/watch?v=9BI_MAkFBIU


#3

T-motors are great, I’ve been working with them too in the past and they’ve always been really open and helpful.

Few questions/thoughts:
-Why are you going with the 170kV version. I would have thought the 120 or even the 100kV would have been more adapted to an heavy load… Current motors are 180kV but they’re designed for 22" props.

-Prop size recommended for those P80 is 28-30", a 26" prop would probably work but will most likely result in a considerable lost of thrust.
Also like Lukas mentioned the frame is now designed for 22-23" prop.

Edit: 23" is pretty much the biggest props you can go with now.


#4

TMotor can and will do custom windings of motors to make specific KV motors. They don’t make their own props, and the company that does requires a very large order to make custom designs. If you go with TMotor’s alpha escs, you can get their Data link which allows you to change esc settings, log data, and more.


#5

Hey @MayMayDay, Are you still working on it? I’m also from the drone industry and gimbals (I’m CEO at www.slick.video) and want to build a PPG. Want to get in touch?

Tom


#6

Haven’t had much time to do design work yet unfortunately (been overseas for the past month for work), though I’ve been brainstorming a lot. Aiming to go bigger prop (29-30") and get efficiency up with custom motors and ESCs. Newer high density lipos for more bang for your buck. It’s a slow going process but it’ll get there…

I want 30min to be standard for 4 packs, if not more.

Want to stick a gimbal on it? :stuck_out_tongue: