MR60

Worlds Best ESC - Making it Better

That's a bold statement ... Worlds Best. But it's even larger than that. Not just Worlds Best, but best for most all applications less than 30 Amps (limit of the tests). That means:

- duration ships that only pull 2 to 8 amps per rotor

- most all 6S and smaller ships (exception of nano-ships)

- any-size FPV racer

- any other ship in between

Why almost any size? Shouldn't a small FPV racer use a smaller and lighter ESC for response? Yes, if it does better on a net-lift response test. In other words, when you penalize the ESC for it's weight, is it still better and faster? What i continue to see is ESC manufacturers downsizing critical components of the ESC at a net loss. They weight savings is lost because of greater thrust loss and response. In other words, this heavier ESC will out accelerate, in the real world, a smaller and lighter ESC.

Why post this? To move technology forward, we need to report to industry what works and what doesn't. For some reason (i don't know why), this ESC works better than all others tested:

- for generating maximum thrust from the motor***

- for net-lift efficiency or the grams of weight it can lift (after it lifts the rotor) per watt

- for response (how fast it can generate targeted lift)

These tests were conducted on multiple days on multiple rotors of highly variant size, always being immediately compared back to another DYS 40A multicopter test to ensure that the baseline wasn't changing.

The ESC that dominated is a DYS 40A OPTO Multicopter using SimonK. The photo is included because there are two others that carry a similar or same name.

- Not the white cover DYS BLHeli 40A

- Not the one that is says "Programmable" versus "Multicopter" in the blue/purple band across the front

3691280727?profile=original

Have i tested all ESCs? No, but if you are convinced you know of one that would work better, let me know. I've tested most all of the following and one or more of their variants:

- DYS

- Multistar

- Turnigy

- T-Motor

- Afro

- Motortron

- Quattro

- 3DR

- Spider

- KDE

- ZLW

- Aris

- EMAX

- AutoQuad

- Exceed

- HobbyWing

- Lumenier

To do a test like this, a highly repeatable and finite test stand is needed. It took a while to develop one but what works is one that:

- measures (at a minimum) volts, amps, thrust, motor temp (shoots IR up the aft end of the motor)

- eliminates harmonics between the rotor and load sensor (this proved difficult but achievable)

- is calibrated and proves repeatable within 1.5%

- controlled by a system that can precisely repeat a rotor test (uses a Audurino Mega)

- directly feeds the data into Excel for analysis (uses DATAQ)

- uses a test script that produces repeatable results

- uses a test procedure that minimizes repeatability error (used average of multiple tests)

How much better is this ESC?  On average:

- 4.4% higher net lift (after it lifts itself)

- 2.3% more net-lift efficient (usually the larger the better)

- from more than twice the response or the same response as other ESCs (usually the larger the better)

                                                       So how to make it better?

Step 1: Strip it naked. See photo below.

           ... remove the cover

           ... remove the heat plate (better to locate the ESC under prop wash to run cooler, see below)

3691280569?profile=original

Step 2: Right-Size the bullet connectors or wires (see above where heavy wires are replaced by 2mm bullets)

           ... remove the large bullet connectors or wires

           ... replace them with ones that are the most net-lift efficient (where heat loss = weight loss)

Step 3: Seal the ESC. Seal it with Electrical Sealant to protect from moisture and conductive dust

           ... tape or plug connectors and wires

           ... repeatedly spray each side from different angles

           ... a mistake i made was not sealing the bullet connectors and solder

               - don't tape them off like i did

               - insert a male connector into the end of bullets so sealant doesn't get inside them

3691280655?profile=original

Step 4: Locate ESCs under Prop Wash. See photos below. The turbulence generated by the prop does not adversely affect lift when the ESC is placed on edge to the prop wash.

           ... Use something non-conductive like hot glue to bond the ESCs to the motor mast or spar

           ... Face the FETS (the little square warehouses or Fire Emitting Transistors) to open air

           ... Protect the ESCs from below from ground contact (not needed here because of clearance)

back-side with hot glue

3691280584?profile=original

front-side with FETs completely exposed to open prop wash

3691280749?profile=original

Step 5: Tie up wiring. Use dental floss to secure wiring away from the prop.

***Note: The T-motor Air 40 in high-timing mode (an option) generated higher thrust, but at the sacrifice of efficiency and motor temp. Also, the T-Motor Air 40 was 2nd best and close in performance. If you are using an Air40, it probably isn't worth switching.

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

          • I'm not sure that our theoretical wet noodler has ever built an MR.  Demanding photos to validate actual experience was good for about a week.  Now I just take solace in knowing that it takes him much longer to BING and Wiki his comments than it takes for me to spot his name on a post and skip it.  

            Catching him in obvious theoretical errors (a power meter to control altitude?) fails to shame him into silence; perhaps we should try ridicule.  At least we can enjoy each others ripostes. 

            The only true harm is when a poster with actual knowledge of the topic wastes their time trying to sort out the drivel, and becomes discouraged from sharing their expertise.

            • I really don't understad what impulse a man to show him ridiculous discussing bad with people that have lot experience like Forrest, world longest flying time guinnes with a Diy dron designed with an innovative construction techniques, with percises calculations, sharing all what he did to discuss with comunity, showing his obiously more knowledge from the average people and well recognized by this comunity, and, in the other side a man that's never assemble and fly a Drone, only a solar Kite as He recognizes¿???, Is like I bad discuss with Randy or Tridge about codes but I never wrote a line; only Bing and Wiki that I hope anyone read now. Perhaps It's better a RTF forum users to caugth unprevented clients for his "services" but not a diy community.¿???

              • Did he have to look up 'solace', 'riposte', and 'drivel'?

                I'm not as nice a person as Forrest is.

        • MR60

          thanks for the tip on liquid tape. didn't know about it. Amazon sells it in white, red, green, and black. just ordered some.

          correct on the dental floss (it's weight). my favorite is zip ties. ties don't weigh that much and are easier to tie. but dental floss (my brother Jim got me onto that) throughout a ship will save 6ish grams. if dental floss can cut into tarter, then who knows ... we should probably ask permission from OralB before using it on drones. maybe our friend can do that for us.

          congrats on being a scoutmaster. is there a merit badge yet for drone or robotics?

          • Using Liquid Tape: Open the bottle.  Put a dollop of material on a disposable work surface (I use masking tape). And close the bottle.  The solvent in the tape evaporates very quickly.  If you try to work from the bottle taking a little at a time, you'll wind up losing the last half of the bottle as it degrades into a thicker and thicker sludge.  I use the left over ends clipped from zip ties as applicators to work from the dollops.

            Heat Shrink Wraps: I'd think that a lot of the cooling loss under shrink wrap is the trapped air inside the plastic cocoon getting warm.  Warm air only bleeds out slowly from the ends, and you lose your cooling gradient, which slows heat migration.  Nekkid seems like the way to go as you have a more direct path to cooler air.

            (Lewis Grizzard joke:  'Naked' means that you have no clothes on.  'Nekkid' means that you have no clothes on, and you're up to something!)

            Robotics Merit Badge:  

            http://www.meritbadge.org/wiki/index.php/Robotics

            • MR60

              Nekkid it is :-)

              I've only had 2 cups of coffee so far but have no idea what the threads on the merit badge are trying to represent.

              • Hehe, took me a bit to figure it out, but I think it's supposed to be a Mars rover.  Perhaps the designer never got their graphic design merit badge...

            • Thank's Joe, for user recommendations

          • Perhaps white is better to absorb less temp from sun. 

This reply was deleted.

Activity