Azimuth mount for the T100 / T200 series

The mounts arrived today. I’ve been very impressed by the quality of work from Simon, Spally definitely has a top quality 3dhub in his area. Also visible in the picture is an Adafruit 5V Trinket…

 

Sliprings arrive tommorow.


Nice! Those looks great. They look really strong. Post a pic of the sliprings when they come in if you can. I’d love to check to them out.

-Rusty

Moflon MW1630 slip ring, 30 amps per line, next to the azimuth mount. It fits quite well inside the inner tube with plenty of room, and it is intended that it will mount on top of the drive gear (suitable through mount hole in the gear).

Also have some gear coming from 01Mechatronics to make this work with modified standard servos (they have some great stuff).

In addition, attached is a new hull design to suit this combination. Shown is the side profile/keel frame which fits on an A0 sheet of paper at full scale (1.18 meter length tug). Might call it the A0 class tug…



Good morning folks,

 

Rusty, what’s the ETA on the release to manufacturing and shipping of the T200’s?

Cheers,

Mike

Mike,

We’re expecting the first batch of shipments in early May and hopefully we’ll ship a lot of T200s by the end of May. Thanks for your patience! We’re working hard to make sure we get them out as soon as we can.

-Rusty

The Supermodified V3.0 assemblies from 01Mechatronics in Greece arrived today. These retrofit straight into any standard size servo, and by removing the stop pin from the main drive gear, ultimately give you a continuous rotation servo capable of absolute positioning. Addressable via RS485, I2C ( my choice for this application) and legacy PPM).

They were not cheap for the pair of them at 165 euros, but offer a nice cheap (in terms of time spent on an alternate solution) solution and are pre-programmed, helping make the whole drive assembly much tidier. I’m considering using a single Arduino as a result to control both drives. I2c to the servos and the BlueESC’s. You can see the original guts of the servo next to the modified Turnigy TGY-901S robot servo.



Will the 01Mechtronics board work with the HS-646WP sold by Blue Robotics? Would this convert it from 180 degrees to unlimited rotation servo?

thanks, Rick

Rick,

We haven’t tested them but the HS-646WP is a standard size servo so I imagine that it would work fine. Perhaps someone else has tried and can share their experience.

I imagine that you would have to reseal the servo to maintain water-tightness.

-Rusty

Hey Rick!

 

As per Rusty’s reply, I also cannot comment in regards to the waterproof servos. I would think the installation of the Super modified assembly would be the same as it was for me, and as he said, your issue will be re-sealing the servo.

And yes, you will get 360 degree absolute positioning (don’t forget to remove the metal stop that limits travel).

Perhaps you can be the first to try and get back to us? :slight_smile:

Thanks for guidance. Will provide feedback if I can/can’t get it to work - Rick

 

I did notice that Servo City’s page on continuous rotation mods

https://www.servocity.com/html/rotation_modification_difficul.html

marks the HS-646WP as NOT modifiable for continuous rotation. Is this table considered to be definitive?

The type of issues they cite stopping conversion to 360 degree operation are

"Some micro servos have a “half pie” shaped final gear that allows the servo case to be very compact but also means that they cannot be modified for continuous rotation. Others have the final gear resting directly on top of the potentiometer which means the potentiometer can not be removed and yet others need to have the final gear drilled out. "

Is the internal design of the HS-646WP available on line, to see if there any gotcha for 360 mod?

(The Amazon reviews of the HS-646WP indicate that people have opened this unit up and resealed without major incident.)

 

Some progress made though only a little… Slip ring fitted. 2mm of plumbers tape around the slip ring body for a snug alignment in the inner tube. This then allows the slip mount holes to be elongated so it can be directly screwed to the inner tube. Next step is design of the gear to fit the top of the slip ring (will be retained by slip ring retainer screws).


G’day folks.

Tested the Super modified assemblies inside the Turnigy servos today, using an Arduino Uno communicating over i2c.

The good news: they work quite well.

The bad news: under the looping test sketch (positioning randomly changes every 10 seconds) both servos destroyed their metal gearboxes within 15 minutes. It seems the Super modified servos accelerate to the new position as quickly as they can and chew gear teeth in the process. Physically rotating the servos by hand while disconnected, clockwise presents no abnormal resistance.

Rotating anti-clockwise presents significantly increased resistance and an abnormal meshing sound from the gearbox. Rate of acceleration will need to be provided along with position I think…

Deckie,

Thanks for the update. The slip ring and assembly looks great. I’m surprised that the servo is strong enough to strip its own gears. I would consider using a different brand of servos - they might have stronger gears.

If you have a chance, it would be great to see a video of the rotation in action!

-Rusty

G’day Rusty,

Unfortunately not mounted to the mounts yet, I have them in a test rig as i’m still sorting out the gears.

Interestingly, the damaged servo will still rotate (poorly) when used with the legacy PWM mode…

Going to look into that this weekend and see if there is a Gremlin in the test rig…

P.S.

The model scale has now changed to 1:32 and hull is now own-design. The drives barely fit in the vertical space available…


G’day folks. Revised lines attached (mount cones added). This yields a further 30mm of clearance from the main deck and is in keeping with modern ASD tug design.


Thrusters have arrived, T200’s #66 and #67. Keel has been cut. Sweet.


There’s been a little more progress finally, main deck frame cut and fitted to the keel, and starting on the frames.

The build-log is running in parallel with the one on RCgroups.com

 

For now, you’ll find updates there:

 

Deckie i love how you created azimuth propeller using servomotors please can you give me your e-mail to be in touch with you, I am building same kind of project and i would like to share information about this.

i will look forward for your reply

Hey, very very nice Project!! I was looking for something like that for quiet some time now!
Is there any chance you could upload the printing files to some place like thingiverse or similar?

 

Thank you so much!!

 

Greetings