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angus40
09-04-2019, 03:25 AM
Buy good quality servos ! The difference is night and day between the medal and plastic geared models .

All may seem fine with the plastic servos until they actually get used in a prop . You can waste a lot of time messing with code settings and just getting frustrated . Settings adjustments can smooth out some things but not all and definitely nothing like replacing the servo with quality . The old saying holds true .
You gets whats you pays for !

Give a listen to this servo compared to the plastic servo I used in the skull .


https://www.youtube.com/watch?v=oHirIf-KP58&feature=youtu.be

ppohlman
09-04-2019, 11:34 PM
I'm looking at getting started in servo props this year. Can you give some suggestions of good servos to purchase?

angus40
09-05-2019, 12:20 AM
These are 2 types I have tested so far .

MG996R Metal Gear Torque Digital Servo >> Quite heavy duty
MG90S Metal Geared Micro Servo >>> much better than the SG90 but still for light duty

ppohlman
09-06-2019, 10:37 PM
Thanks for the suggestions.

angus40
09-07-2019, 01:54 AM
I just ordered a couple of these for heavier lifting .I hope I don't need to go even larger than these . :)
Moving a wolf's head forward and back for a servo is tougher than I imagined .

ANNIMOS 25kg DS3225MG Digital Servo

angus40
09-14-2019, 04:49 AM
25kg DS3225MG Digital Servo

Premium and real strong , best yet and has metal arm/horn .

qubie
02-04-2021, 02:31 PM
Ive just received 4 MG 996R servos
the 1st one i tried was slower than i was expecting and suddenly started doing a 360 rotation i had to power it down to reset it
I wasnt aware that they did not have a mechanical end stop

angus40
02-04-2021, 03:11 PM
Ive just received 4 MG 996R servos
the 1st one i tried was slower than i was expecting and suddenly started doing a 360 rotation i had to power it down to reset it
I wasnt aware that they did not have a mechanical end stop

Sounds like you may have received 360 servos .

The 180's do have a stopper added inside the case . There are u tube videos showing how to modify the 180 to be 360 .
You will need to experiment with the code to find the 90+/90- break point, or return the servos for the correct ones .

Mg996r come in both fashions .

qubie
02-04-2021, 05:10 PM
Bought from ebay the guys listing states max 180 deg rotation ive messaged him so will see what happens

thanks for the reply

Qubie

angus40
02-04-2021, 08:10 PM
Have you tested the others ?
Do they behave the same ?

MartinMueller2003
02-04-2021, 08:31 PM
Did I mention that the ESP32 based version of the ESPixelStick V4 (Unify branch) now supports 16 channels of PWM servo control via a PCA9586 adapter card (just added it this week)?

angus40
02-04-2021, 08:42 PM
Did I mention that the ESP32 based version of the ESPixelStick V4 (Unify branch) now supports 16 channels of PWM servo control via a PCA9586 adapter card (just added it this week)?

Cripes, this gives me the excuse I needed to place another order :)
I am currently looking at these (https://www.aliexpress.com/item/4000402930291.html?spm=a2g0o.search0301.0.0.58b950 ddApP6NF&algo_pvid=a8137361-52aa-460a-a07a-9266bd8c527a&algo_expid=a8137361-52aa-460a-a07a-9266bd8c527a-12&btsid=0bb0623616124626929442175ef00e&ws_ab_test=searchweb0_0,searchweb201602_,searchweb 201603_) for a 32-cam mod .

MartinMueller2003
02-04-2021, 08:47 PM
Cool little beasts. Looking at those and thinking back 20 years. Those $2 cameras would have cost $100.

qubie
02-05-2021, 03:17 PM
WOW thank you
I have 2 pca9586 boards so just ordered 2 esp32's
is the code available for download now or soon although it will take a week or 2 for the esp32's to arrive

once again thanks for the info

qubie
02-05-2021, 03:28 PM
as for my mg669r servo's i tested all 4 using espthing from dirk and they work fine when i test using D1 mini with external 3a power supply and Vixen, 2 do nothing just buzz a little and 2 will work ok then suddenly spin full 360 like it received bad data, then have to power down and start again

MartinMueller2003
02-05-2021, 04:53 PM
WOW thank you
I have 2 pca9586 boards so just ordered 2 esp32's
is the code available for download now or soon although it will take a week or 2 for the esp32's to arrive

once again thanks for the infoThe code is in development. You would need to clone the ESPixelStick Unify branch and build for the ESP32. WARNING: Read the README file. There are MANY libraries that need to be downloaded and some specific tools to create and upload the littlefs image. Shelby will be productizing the ESP32 later. For now you have to build it yourself.

angus40
02-05-2021, 05:26 PM
as for my mg669r servo's i tested all 4 using espthing from dirk and they work fine when i test using D1 mini with external 3a power supply and Vixen, 2 do nothing just buzz a little and 2 will work ok then suddenly spin full 360 like it received bad data, then have to power down and start again

For fun , set the start point to 5 or 10 rather than 0 also set the end point to 170.
It sounds like you are having an endpoint overrun but it should be chattering like heck not running 360 .
Strange behavior if these servos are truly 180 and not purposely built 360.

qubie
02-05-2021, 06:14 PM
Hi Martin thanks for the info, yes i have seen your other posts with reference to read the readme file, I love it, will give it a go when the esp's arrive

Hi Angus the sketch i use i posted here (http://doityourselfchristmas.com/forums/showthread.php?56170-Wemos-d1-mini-servo-controller)

the sketch is for my singing skulls i use the min max of 90 - 45 for jaw movements, for standard servos it works a treat but these being digital and what looks like 360 deg they are acting a little different.
I have to say they are too slow for jaw movement and it looks like they struggle to keep up with the commands from vixen but if i change to 20 - 160 for pan and tilt so far they are working.
i dont want to install them in a skull just in case they decide to spin him around a few times until something brakes

angus40
02-05-2021, 08:52 PM
Hi Martin thanks for the info, yes i have seen your other posts with reference to read the readme file, I love it, will give it a go when the esp's arrive

Hi Angus the sketch i use i posted here (http://doityourselfchristmas.com/forums/showthread.php?56170-Wemos-d1-mini-servo-controller)

the sketch is for my singing skulls i use the min max of 90 - 45 for jaw movements, for standard servos it works a treat but these being digital and what looks like 360 deg they are acting a little different.
I have to say they are too slow for jaw movement and it looks like they struggle to keep up with the commands from vixen but if i change to 20 - 160 for pan and tilt so far they are working.
i dont want to install them in a skull just in case they decide to spin him around a few times until something brakes

I'd be willing to wager 0 is fine & 160-170 is the solve all ! :)

qubie
02-06-2021, 07:06 AM
Hi Angus servos are going back on monday but i will do some more testing over the weekend while i still have them,
a little bit more learning and understanding cant be a bad thing for me thats half the fun, the other half comes when it all works

qubie
02-09-2021, 06:24 PM
Well i never esp32's arrived in 3 days I am amazed, I havent even found my PCA9685s yet
ok martin i read all the readme's ( i bet your impressed) and ESP32 up and running
4426744268

MartinMueller2003
02-09-2021, 06:28 PM
Well i never esp32's arrived in 3 days I am amazed, I havent even found my PCA9685s yet
ok martin i read all the readme's ( i bet your impressed) and ESP32 up and running
4426744268Yippeeeeeee. See Read the READ.ME file and it WILL build. I get to keep some of my remaining strands of hair. Have you looked at the Servo config yet?

qubie
02-09-2021, 06:44 PM
Dont you ever sleep saying that its 22:40 here in the UK so i will be soon
PCA9685 setup looks simple enough just the 8Bit and 16Bit will need some trial and error
I assume I use the I2C pinouts as normal44269

MartinMueller2003
02-09-2021, 07:21 PM
Correct. The default I2C pins are all that we support at the moment.

MartinMueller2003
02-09-2021, 07:22 PM
Dont you ever sleep saying that its 22:40 here in the UK so i will be soon
PCA9685 setup looks simple enough just the 8Bit and 16Bit will need some trial and error
I assume I use the I2C pinouts as normal44269I sleep from 23:00 - 05:30 ET every day (except when I cant stay asleep).