Peter Wallers Robot Ramblings

[Paulmchurd]

What are the advantages of printing in nylon? Can all printers do it?

[peterwaller]

The main advantages certainly with Alloy 910 Nylon is strength and impact resistance.It needs to be printed at 250 - 260 C so it really needs a printer with an all metal head although I have been using it with a Prusa i3 with a PTFE insert but they do deteriorate after a while and need replacing. The disadvantages are the very flexibility that makes it resilient to impacts means it is sometimes not stiff enough in some structural applications and its hard to get it to stick to the glass printer bed, I use glue stick.

[peterwaller]

I have got out of the habit of posting much lately so on the offchance that someone is interested here is a quick catch up.
Finally finished the drum spinner. It was a couple of gms over with just a 120 mah battery so I reduced the scoop on the front and managed t get a 180 mah battery in and stay within the weight limit.

Talking of larger batteries I have been modding a couple of my drive all day robots so they last longer by putting in a 370 mah battery.
The first I was able to just tack it on top.

But the second I needed to rebuild from scratch.

I have also finally replaced the temporary arena lid support for one made of polycarb with 3D printed higes and latches.

[AntRoboteer]

All looks fantastic Pete! Looking forward to seeing that drum spinner. Has it got a name yet and will it feature at the AWS?

[peterwaller]

I haven't actually tried it against anything yet but assuming that goes well it will replace one of my horizontal spinners at the AWS so will be either Anticyclone or Combatant.

[peterwaller]

Although my controller module with the motors included works well in many robots there are times when you need the motors separate or in the case of the four wheel drive below you have to add extra wires.

So using the same board with pins fitted for the motor connections I have come up with another variant as below showing the power, servo and two motor plugs fitted.

The module is 38 x 24 x 11 mm and weighs 8.2 gms including the tiny orange receiver.

[Paulmchurd]

Looks amazing. Looking forward to seeing your robots for the first time. If you will be attending the 13th October meet

[peterwaller]

Just found a new full bridge driver the TLE 5206 which although quite a bit bigger can handle 5 A continuous from 6 v to 40 v.
http://uk.farnell.com/search?st=TLE5206
I have just hooked up one to one of my boards and it appears to work well without any changes the the software.

I have started looking at a layout for a fully plug and play board with power switch which looks to be coming out at around 30 mm x 31 mm

[Lincoln]

why's it 31x30mm? what other chips are you using that makes it so large? i mean that is still pretty small but i made the smart-board 21x20mm and that has a lot of features. are you trying to use hand soldering? i find then all the chips are usually a bit larger. for example the auto-bot board would be a lot smaller if i got it soldered by a company rather than hand soldering everything.
great work as always Pete would love to see details of your board.

[peterwaller]

The size is mainly down to the 5v 1.5A regulator two of these chips and the orange receiver and power switch which make up around 75% of the area.
The rest is just a ATTiny24 processor some decoupling caps and the power servo and motor connectors to make it plug and play.
I could have used smaller connectors and components on both sides but it wouldn't have been that much smaller and the power and servo connectors need to be 0.1 pitch to match existing batteries and servos.
Excuse the screen shot which is literally a photo but my 1998 circuit board package only runs on an old Vista machine and it was the quickest way.