What about increasing the PWM voltage on the stock Cube ?

[Pedals2Paddles]

..... or simply reduce the MOT_BAT_CURR_MAX parameter to stock setting.

That will not protect the solo from the ESC problem. Placebo.

 

[VCD]

..... or simply reduce the MOT_BAT_CURR_MAX parameter to stock setting.

no, MOT_BAT_CURR_MAX is based on total battery pack current (when reported by smart battery, which is much less frequently than throttle changes) The fault can happen if one motor increase throttle to quickly, getting a voltage drop, setting a limit on all four does not make sense. You would need to set max current so low, that in case three are idle, one needs to rise quickly. That would not be good at all if all four needed to speed up.

 

[fpvsteve]

no, MOT_BAT_CURR_MAX is based on total battery pack current (when reported by smart battery, which is much less frequently than throttle changes) The fault can happen if one motor increase throttle to quickly, getting a voltage drop, setting a limit on all four does not make sense. You would need to set max current so low, that in case three are idle, one needs to rise quickly. That would not be good at all if all four needed to speed up.

This is correct. Setting the CURR_MAX parameter to 40 Amps (the original 3DR setting) will not prevent critical voltage drops for an individual motor nor will it be as accurate as a slew rate limiter. However in practice it seems to work for all situations I tested now on 2 Solos over 9 months. So far I could not reproduce any ESC failure or hickups on my Solos no matter how hard I tried. Details of my observations here:
https://3drpilots.com/threads/3dr-solo-escs-firmware-updates.11409/page-3#post-120697

Disclaimer: Dont try this mod in areas where a crash could harm people or property.

 

[porlock]

And what about change a max pwm value for ESC ? Like in 3dr branch, it is one liner change, it should help afaik.

 

[Pedals2Paddles]

And what about change a max pwm value for ESC ? Like in 3dr branch, it is one liner change, it should help afaik.

I won't. The PWM maximum isn't to protect the Solo from anything. It's for the purpose of thrust scaling. Through testing, 3DR determined the motor and prop combination maxes out thrust at a PWM value of 1869 (I think that's what the number was). The rest of the throttle range from 1869 to 2000 does not produce any additional thrust. So if the throttle range went all the way to 2000, it would make the very top of the throttle stick useless. By setting the ESC saturation point to where thrust really maxes out, ArduCopter can properly scale the throttle input and output.

The ESC failure issue does not require the throttle to hit maximum. It is the rate of change, and the load on it during that change, that lead to the ground bounce. Maximum throttle not required.

 

[5r49cfu]

That mod (madhacker) does work, but it is not for the faint of heart. Although pro SMD rework folk can do it in a flash, unless you know one or are one it is not going to be an easy mod. I have done 3 PixHawk 2.0's, the first was hard, the second was a lot easier, the third was a bi$%#tch. Don't try this at home. While it can be done and provides the same (mostly) effect as moving to a Green Cube, I would strongly suggest acknowledging it as cool but GO OUT AND GET A GREEN CUBE!
I may do #4 but only after another month of recovery ;>))

You cannot get a green cube any longer (Hex stopped shipping to the US).

Looking at Jed’s website, it sounds like he does the mod above on the regular PH2.1, and makes it “green”.

I think...

 

[cynfab]

A PH 2.1 has a jumper (well you have to cut a small trace and solder to the alternate point, but I digress) to set the PWM signalling voltage. It can be either 3.3V or 5V (nominal). Anyone can buy a black PH 2.1 and turn into a Green PH 2.1. (or vice versa)
Jester's Drones has stock in the US and is running a special now:
The Cube Only, for 3DR's Solo Platform, this is Experimental
the PH 2.1 web site also points to several other US and international dist's.:
Stores - Pixhawk2
You can even get one (black) from Amazon, it's bundled with the carrier board, but you can get it before Christmas (you will have to change the jumper though):
https://www.amazon.com/Pixhawk-Auto...rd_wg=w2drg&psc=1&refRID=F2MK10HPD8C9YNTTGB6E

The madhacker mod is NOT the same thing, it is similar in effect, but not the same.

 

[Pedals2Paddles]

Hex is not selling them directly. That's all that's changed. You need to buy it from a distributor like Jesters. And no, Jesters is not modifying cubes. Nothing has changed.

 

[5r49cfu]

Hex is not selling them directly. That's all that's changed. You need to buy it from a distributor like Jesters. And no, Jesters is not modifying cubes. Nothing has changed.

From Jester Drones website on the green cube page:

IMMEDIATE SHIPPING.
Do to Overwhelming Demand, these will not actually be a green cube, but a black cube with a marking noting it's purpose. In order to meet the community needs, instead of waiting on a long production, the factory is making the internal changes needed to meet Solo's requirements.​

That sounds like someone is doing manual rework of a regular PH2.1 cube

 

[Pedals2Paddles]

Are you reading what you just posted? It says "the factory is making the internal changes needed to meet Solo's requirements.".

The original production run of the Green Cube was the cube built from scratch with the voltage jumper set for 5v instead of 3v, and with a shiny green case. That original production run has been sold. So what they're doing now to meet demand is simply setting the internal jumper of a cube that just came off the production line to 5v, and putting a green sticker on the top. Nothing has changed.

The alternative is waiting months for a new production run just to have a pretty green case.

 

[5r49cfu]

Are you reading what you just posted? It says "the factory is making the internal changes needed to meet Solo's requirements.".

The original production run of the Green Cube was the cube built from scratch with the voltage jumper set for 5v instead of 3v, and with a shiny green case. That original production run has been sold. So what they're doing now to meet demand is simply setting the internal jumper of a cube that just came off the production line to 5v, and putting a green sticker on the top. Nothing has changed.

The alternative is waiting months for a new production run just to have a pretty green case.

my point is that the madhacker.org cut/jump rework looks difficult and prone to problems.

if that is what "the factory" is doing, then it would be good to know

 

[Pedals2Paddles]

The stock pixhawk 2.0 cube mod as shown in this thread? Totally different hardware. The stock cube does not have a solder jumper. What you see in this thread is nothing like the Pixhawk 2.1 design.

 

[5r49cfu]

The stock pixhawk 2.0 cube mod as shown in this thread? Totally different hardware. The stock cube does not have a solder jumper. What you see in this thread is nothing like the Pixhawk 2.1 design.

Ok good to know, whew.

 

[5r49cfu]

Ok good to know, whew.

Green cube from Jester is inbound

 

[User Name]

There is no logic level converter in the stock pixhawk 2.0 that you can modify to make it do 5v per the guy who built it. You would have to do it externally. Plug making it something you plug into the port on the carrier and then plug the motorpod wires into would be best.

When I probe the 8 pin connector going to the ESC, I don't see any wire with either 5 or 3.3 volts. Pins 5 and 6 (from the red wire) have a consistent 2.3 or so volts, 7 and 8 bang back and forth between about 2 to 3 volts. From what I've read, pin 4 is the PWM signal.

For a totally in-line voltage shifter board, if pins 5/6 had the capacity, you could boost the 2.3 volts up to 3.3/5 for reference voltages for a shifter circuit. I've made both (boost and shifter circuits) for arduino projects, but that more knowledgeable people haven't made up small in-line boards for the Solo yet makes me think there's more to it than meets the eye. If not, I'd be willing to take a shot at it.