Drive Components for my Robot.

[Alex McClung]

Hi Guys,

I'm rebuilding my robot onto a new chassis made of Openbeam. 

One of the main differences will be the drive system:

Instead of a direct drive system, I would like to use a 3:1 Timing Belt system and new 8 Inch wheels.

I'm using Jaycar YG-2738 Motors (6mm Shaft). http://www.jaycar.com.au/productView.asp?ID=YG2738

The wheel brackets will be made of Openbeam and Skate Bearings (8mm Bore Diameter), mounted Vertically Below the Motors:

http://www.openbeamusa.com/Speciality-Components/NEMA-17-Mount-Plate-2-pack.html

http://www.openbeamusa.com/Speciality-Components/608-Bearing-to-NEMA-17-Mount-Plate-Adapter-2-pack.html

I don't have much experience with this sort of stuff and I'm not sure what Pulleys and Belts i need.

If someone could help out, it would be greatly appreciated. :)

Cheers,

Alex

[Dave Everett]

Alex, given the size of wheel I would recommend XL timing pulleys. XL is 5.08mm pitch. There is a metric version T5, but choices can be more limited for one-off constructions.

 

Stock Drive Products sell timing pulleys and belts in most configurations, they also have a centre didtance calculator for determining the distance between the pulleys (note it is not entirely accurate and I tend to check the true distance once I receive the parts, but you will be within a few millimetres). Their website is:

http://www.sdp-si.com

 

They sell plastic pulleys which are very cheap and nice to work with and you can buy a pulley with hub and set screw with the correct bore to fit the Jaycar motors off the shelf.

 

If you're going to be down at the workshop any time soon, I have my new base on the back table, it uses an XL belt system to bring the speed down to around 80cm/sec and improve the torque.

 

I am using a pnuematic wheel from Fallshaw casters as the hub is bolted together and I was able to use those bolts and some couplers to attach the large timing pulley and keep everything square. I also printed a template on the 3D printer for drilling the holes in the pulley so they match up exactly with the bolt holes in the wheel.

 

Dave

[Alex McClung]

Thanks Dave,

Ive looked on their website, but i'm not sure exactly what i need. They have hundreds of configurations and i want to make sure it will work before i purchase.

They don't have any 8mm Bore, XL Pulleys with anywhere close to the 60 grooves.

So i had a look at T5:

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=60018&GroupID=346 Motor Pulley.

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=59730&GroupID=346 Wheel Pulley.

Will they work together?

Alex

[Kean Maizels]

Alex,

 

Take a look at http://ausxmods.com.au/ for T5 timing belt and toothed pulleys.

No affiliation, just a happy customer.

 

Kean

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[dyrodium]

Was about to recommend ausxmods too. Great prices and in NSW to boot.

For driving your jaycar motors I would recommend some bulletproof botbitz 85as if you don't already have speed controllers!

[Alex McClung]

Thanks Guys, I've already got Motor Drivers and all electronics.

I'd already ordered the pulleys and belts before i knew about ausxmods. I ended up getting:

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=60018&GroupID=346 Motor Pulley.

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=59730&GroupID=346 Wheel Pulley.

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=85139&GroupID=342 Timing Belt.

Alex.

[Ming Yu]

Hey guys, 

I'm working on a simple project. I bought a spy pen camera, and using its electronics, I want to link it to a piece of glass (size of normal spectacles). Got inspired by google glasses, so wanted to replicate it. 

Does anyone have any idea how to link the 2 components together.

Thanks

Ming

[David Lyon]

Google have a lot of money to put into their projects. Stuff that 'looks-easy' ain't always
that easy to project manage and make.

Why not post a picture of the parts that you have so far so we can comment from
there.

Need more information to be able to tell you what to connect where to where.

[Dave Everett]

On Saturday, November 17, 2012 8:39:58 PM UTC+11, Alex McClung wrote:

Thanks Dave,

Ive looked on their website, but i'm not sure exactly what i need. They have hundreds of configurations and i want to make sure it will work before i purchase.

They don't have any 8mm Bore, XL Pulleys with anywhere close to the 60 grooves.

So i had a look at T5:

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=60018&GroupID=346 Motor Pulley.

https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=59730&GroupID=346 Wheel Pulley.

Will they work together?

T5 is fine, it's almost the same as XL, so T5 pulleys and T5 belts would do the job fine.

 

Kean, good resource there, those prices are very good.

 

I checked up my last order, on those pnuematic wheels I used a 70 tooth pulley and a 20 tooth on the motor to get the speed and torque where I wanted them. If you got the 60 tooth for the wheel and the 15 tooth for the motor, you would get a similar ratio. The 15 tooth has a 6mm bore so will fit exactly on the Jaycar motor. The other pulley, you bore out the centre of.

 

You'll want to check that the 70 tooth pulley has enough space to place the screws to interface with the screws in the wheel (that is the bolt circle can be accommodated in the pulley). That may not be clear so I'll post a drawing. As you can see, the screws that hold the pulley to the wheel must fit within the pulley itself. I used standard M6 couplwers to attach it to the wheel.

 

Either way I would say ausxmods is the go, I'll be getting stuff from them in the future as I would prefer to buy locally.

 

[Alex McClung]

Thanks Dave,

Ive already purchaced a 20:60 tooth system of sdp-si.com, it looks like i have to make up a custom hub.

Two questions:

1. I ordered the 60 tooth Pulleys without flanges, will this be a big problem?

2. Will 120mm be long enough between the origins of the pulleys?

Alex

[Ming Yu]

I dont have the parts yet because I still not too sure what is needed. But just want to find out if it is even possible to use a glass screen and link it to a camera. 

Is there such a screen and if so whats it called.

thanks

---

Date: Tue, 20 Nov 2012 17:37:16 +1100
Subject: Re: Want to take spy pen camera electronics and hook up to a mini monitor
From: david.lyon...@gmail.com
To: sydney-h...@googlegroups.com

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[Lachlan Horne]

What you want is a head-mounted display (HMD). If you also want to see through the display (have the image overlaid on the background) you need a transmissive (? transparent?) HMD. These are not cheap.

I imagine what you want to do is have the camera transmit an image to your glasses. Look at RC aircraft FPV systems (eg. FatShark) to see what is involved with this.

[David Lyon]

On Wed, Nov 21, 2012 at 10:44 PM, Ming Yu <kmyj...@hotmail.com> wrote:

I dont have the parts yet because I still not too sure what is needed. But just want to find out if it is even possible to use a glass screen and link it to a camera. 

Is there such a screen and if so whats it called.

Here's a link to some of those glasses:

 - http://www.aliexpress.com/item/72inch-vision-video-glasses-PMP-glasses-head-mounted-display-DHL-Free-Shipping/553912240.html

from the list here:

 - http://www.aliexpress.com/wholesale?SearchText=head+mounted+display+glasses

They include what looks to be a AV camera input (which is definitely what you want).

So yes it looks possible. There's a few different ways that video is transmitted (NTSC/PAL etc)
but converting is easy with the right adaptor.

Looks possible.

[David Lyon]

On further investigation:

 - http://www.aliexpress.com/item/Wholesale-4GB-8GB-USB-Spy-Pen-Camera-Mini-Hidden-Covert-Digital-Video-Recorder/679535141.html

This spy pen has a built in USB interface and the glasses also have a mini-USB interface.

It may be as simple as record video on the pen, and plug the pen into the glasses to
watch the earlier recorded video.

There's a chance that it may work out of the box.

[Dave Everett]

On Tuesday, November 20, 2012 9:28:09 PM UTC+11, Alex McClung wrote:

Thanks Dave,

Ive already purchaced a 20:60 tooth system of sdp-si.com, it looks like i have to make up a custom hub.

Two questions:

1. I ordered the 60 tooth Pulleys without flanges, will this be a big problem?

 

No, as the 20 tooth has flanges it will keep the belt square. My original setup had no flanges on the large pulley. 

 

2. Will 120mm be long enough between the origins of the pulleys?

 

That's plenty, I think I only have 100mm between centres. However don't place anything until you get the gear, that will allow you to have the best tension and least play in the system.

 

What belt did you order?

 

Dave

[Alex McClung]

I'm glad it will all work well, I wasn't planning on setting it up until i recieved all the parts.

This is the belt i purchaced: https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=85139&GroupID=342.

Alex.