T_Y's Build Log

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Paulmchurd
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Re: T_Y's Build Log

Post by Paulmchurd » Mon Jun 11, 2018 8:41 pm

It’s a lot cheaper to build an arduino speed controller. You can see on my build diary how I did it and the price. I’m happy to show you how to do it if you wanted to meet up again? I’ve been using 4 differnt speed controllers. Except the nano 2... as I don’t have a dsmx Tx.

Issue is the sheer farce of soldering and wiring it all together to fine out you soldered something wrong/a solder pad comes off.

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DieGracefullyRobotics
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Re: T_Y's Build Log

Post by DieGracefullyRobotics » Tue Jun 12, 2018 6:28 am

The Nanotwo does DSM2 and DSMX
Dave
Die Gracefully Robotics - Barely Even a Proper Team.

T_Y
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Location: York

Re: T_Y's Build Log

Post by T_Y » Tue Jun 12, 2018 9:42 am

An Arduino controller sounds like an interesting project to do! I'm wondering if it's possible to connect a normal receiver's signal wires to the IO pins on the Arduino instead of using the NRF24LO1, so I can just use the transmitter I've already got instead of custom building one.
Thomas
Hello, World! - Antweight Front-hinged flipper
Percussive Maintenance - Antweight 'axe'bot (rebuilding)
Have You Tried Turning It Off and On Again? - Antweight 4-bar lifter (designing)

Paulmchurd
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Re: T_Y's Build Log

Post by Paulmchurd » Tue Jun 12, 2018 9:49 am

T_Y wrote:
Tue Jun 12, 2018 9:42 am
An Arduino controller sounds like an interesting project to do! I'm wondering if it's possible to connect a normal receiver's signal wires to the IO pins on the Arduino instead of using the NRF24LO1, so I can just use the transmitter I've already got instead of custom building one.
Yes you can, it's actually better to do it that way then use the arduino transiever modules.

There is a pretty good video on it via sparkfun. However you need to use the same H-bridge they do. Which uses a lot of I/O. There are better h-bridges.

If your interested in setting one up. I can email you all the code I've used. Or we could arrange a meet up and I can show you/battle test our bots.

T_Y
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Location: York

Re: T_Y's Build Log

Post by T_Y » Tue Jun 12, 2018 10:16 am

Those Sparkfun videos are quite handy! It looks like that code can be adapted fairly easily to work with other H-bridges, the logic for interpreting the signals should be similar I would guess.

A meetup sounds good, looking at bots that other people have put together would be interesting, plus getting some more driving experience would help!
Thomas
Hello, World! - Antweight Front-hinged flipper
Percussive Maintenance - Antweight 'axe'bot (rebuilding)
Have You Tried Turning It Off and On Again? - Antweight 4-bar lifter (designing)

T_Y
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Location: York

Re: T_Y's Build Log

Post by T_Y » Fri Jun 15, 2018 2:37 pm

I've been printing off and cutting parts for Hello, World! Put the shell together and 'borrowed' electronics from Percussive Maintenance while I wait for the Arduino and co. to be delivered. I printed off a load of different length pieces to test out, this is the 'best' I've managed so far:

https://youtu.be/QTx7x1HFgf8

Observations I've had about this setup:
  • The flip is quite fast.
  • Rudder-firing the weapon allows for a fire/retract in one stroke of the rudder control, depending on the length of the link arms between the motor and the flipper. Could be useful if you don't want to expose your flipper/insides to an attack?
  • It's not the most powerful of flips. While it can shift 150g (the block of electrical tape taped together), it does struggle a bit, and it can't lift itself when it is inverted.
I'm currently printing off more different shaped/length parts to fiddle around a bit more to see if I can get more power out of the flip. I'm also wondering if reducing the speed of the motor might make it more powerful?

Also, I managed to discharge a cell in one of my LiPos below 3V, which means it's basically dead now, right? How should I dispose of it?
Thomas
Hello, World! - Antweight Front-hinged flipper
Percussive Maintenance - Antweight 'axe'bot (rebuilding)
Have You Tried Turning It Off and On Again? - Antweight 4-bar lifter (designing)

Dazmund
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Re: T_Y's Build Log

Post by Dazmund » Fri Jun 15, 2018 9:21 pm

Hello World! looks absolutely gorgeous. I always wanted to build a front-hinge flipper (or a Lightning-esque side flipper) once I finished my other antweight (still have to do better soldering on it), and this is what I wanted it to look similar to!

The use of a motor to power the weapon is unusual though. I've seen it used for axes and the like. Not sure if it has the torque or lift than a good quality servo but I'm not an expert.

T_Y
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Re: T_Y's Build Log

Post by T_Y » Sun Jun 17, 2018 10:26 am

Front hinged flippers are probably my favourite weapon (go Firestorm!). I do have a servo but it's larger and slower than a gear motor, and I had some spare gear motors lying around. To be fair, I just wanted to experiment a bit!
Thomas
Hello, World! - Antweight Front-hinged flipper
Percussive Maintenance - Antweight 'axe'bot (rebuilding)
Have You Tried Turning It Off and On Again? - Antweight 4-bar lifter (designing)

T_Y
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Location: York

Re: T_Y's Build Log

Post by T_Y » Sun Jun 17, 2018 7:33 pm

The Arduino arrived, so I've been tinkering around with it over the weekend.

https://www.youtube.com/watch?v=DyEzU7FPGTc

The code is based on Sparkfun's videos on RC control. I modified the code to work with my motor driver, which does not have a separate PWM channel to control speed for each motor, instead it accepts PWM directly on the input channels. I've also added a failsafe so that the motors stop turning if connection to the transmitter is lost (the built-in LED will light indicates a connection).

I still need to wire up the rudder channel to control another motor so I can power a motor-based weapon. Once that's done, I need to reduce the profile so that I can fit it inside a bot. I think I've made an error in this regard by soldering all of the pin headers, it's going to be difficult to remove them! It's probably easier to just get another set of components and hard-solder those instead of trying to de-solder everything seeing as the setup is cheap, might not arrive in time for AWS though.

The setup costs around £12, around £4 each for the Arduino Pro Mini, 2 motor driver and the single motor driver (once it's wired up). I used this dual channel motor driver for drive and will be using this single channel motor driver for the weapon.
Thomas
Hello, World! - Antweight Front-hinged flipper
Percussive Maintenance - Antweight 'axe'bot (rebuilding)
Have You Tried Turning It Off and On Again? - Antweight 4-bar lifter (designing)

Ant Ipodean
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Re: T_Y's Build Log

Post by Ant Ipodean » Sun Jun 17, 2018 10:17 pm

A tip I figured out, when removing/desoldering multiple header pins ..
Carefully prise the plastic pin holder off first, then desolder and remove the pins individually.

Mike.

T_Y
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Location: York

Re: T_Y's Build Log

Post by T_Y » Fri Jun 22, 2018 12:26 pm

After many hours of (re)soldering I finally managed to get all of the electronics into Hello, World! Weighs around 120g.

Image

Image

The components are temporarily held in place by blu-tack, I'll replace it with velcro before AWS.

My soldering and wiring leaves a lot to be desired. It doesn't help that I seem to have a knack of designing shapes that only JUST fit everything inside! The wiring is a mess because the white wire I bought had very thick insulation, so it didn't flex very well which would have meant even more difficulty getting everything in there. I've tried to remedy this by wrapping bits of white electrical tape around the wires that would have been white.

Gonna get to re-coding the Arduino after lunch, I had to move around a load of connections in order to get it to fit!
Thomas
Hello, World! - Antweight Front-hinged flipper
Percussive Maintenance - Antweight 'axe'bot (rebuilding)
Have You Tried Turning It Off and On Again? - Antweight 4-bar lifter (designing)

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voorsk
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Re: T_Y's Build Log

Post by voorsk » Fri Jun 22, 2018 1:09 pm

Nice! Some fine packing, there. :D
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon

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DieGracefullyRobotics
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Re: T_Y's Build Log

Post by DieGracefullyRobotics » Fri Jun 22, 2018 1:30 pm

That's a damn fine looking antweight.
Dave
Die Gracefully Robotics - Barely Even a Proper Team.

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peterwaller
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Re: T_Y's Build Log

Post by peterwaller » Fri Jun 22, 2018 2:00 pm

That is a good looking robot and an amazing amount of wire crammed in.
I have had problems in the past getting all the wiring in which is why am experimenting with controller modules that though bigger than some reduce the need for external wiring by including the power, servo and motor connectors plus the power switch and in one case the motors.
This hopefully will not only decrease the overall volume and weight but also improve reliability. :roll:

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GeorgeR
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Re: T_Y's Build Log

Post by GeorgeR » Fri Jun 22, 2018 2:24 pm

That's a great looking robot, looking forward to seeing it next week!
Team Zero
Zero - rambot - - Axiom - axebot - - Valkyrie - drum spinner
Vampire - horizontal spinner - - Orion - horizontal spinner walker (coming soon)

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