Team Saint Robot Builds

[epicentre]

Why mecanum wheels? I would've thought either a 3-motor setup with 3 omni wheels, or a 2-motor setup with 2 omni wheels each, would be much more suitable for this sort of thing. I'm not sure mecanum wheels will work properly, if at all, on a non-flat surface, and I'd certainly expect the movement to be less smooth than with omni wheels.

[craig_colliass]

Hi Scott

The best part about this project is I have not done anything like this before, and I don't know what will work.
After receiving the wheels I am thinking the same thing, and I might go for the 3 wheel setup. later
The sphere
I am still finding no useful balls for the main body, will keep looking. any possible leads welcome. (500mm diameter split-able and plastic)


With regard to Gabriel
I have turned my attention to the Torque limiters on the drive wheels.

IMG_1082.jpg

Because of the damage done to the transmission by flippers flipping the wheels. I am now making torque limiters in the hub centres.
the Idea is to let the wheels spin on the hub when too much force is back driven into them, the first attempt to do this has been quite successful.

[harry hills]

I think 3 motors 3 wheels would be better. You'll have 3 point contact (think like a 3 legged stool) which to my mind works a lot better.

But as you say, its all an experience. I really hope you have a lot of fun with this one!

[RogueTwoRobots]

Hope you don't mind me sharing this here Craig, it's part 2 of the BB-8 build that someone is doing on Youtube. I posted part 1 earlier. He's doing it slightly differently from yourself (due to him building it before the SW convention appearance of the physical droid) but it's fascinating and enjoyable watching nonetheless and thought it may be of general interest.

https://www.youtube.com/watch?v=Ji3wzLkiayc

The 12-minute mark is where it's self balancing on both axes.

[craig_colliass]

Finished the links for Gabriel one shown here. the back plate with the pull tab is about 5mm Polycarbonate

IMG_1088.jpg

The fuse format shown below should fit this type of link too, and is rated at 150A just in case the 100A fuse fitted dose blow under normal conditions.

BTW has anyone else used 2 Roboteq AX2550 (as single channel controllers) in one robot before?

[craig_colliass]

Hi I'm looking for a gismo that can be connected to speed controllers that drive fan motors. the idea is balance
imagine a horizontal board that can pivot in the centre, with 4 fans fitted front back left and right, if the board is pushed down at the front the front fan will run to raise the front, and the rear fan would run to push down the rear until the horizontal plane is maintained then the fans stop.
I'm thinking the multi rotor units must have something like this on board, any ideas?

[grant_ploughbot]

Most general multirotor controllers should do somewhere close to what you want - the difficulty will be finding one that will work with the fans stopped. Normally they need to be activated and start the props spinning slowly to work.
A potentially simpler way may be to use a standard gyro with the output to the fans?

[craig_colliass]

http://www.hobbyking.co.uk/hobbyking...uthorized.html

Would this thing do and has anyone used this before?

thanks

[craig_colliass]

Perhaps this one may be ok has anyone used anything like this in the past?

http://www.ebay.co.uk/itm/F14116-EAG...-/131504768903

[craig_colliass]

My first attempt at moulding plastics was a complete success, It is defiantly moulded

IMG_1096[1].jpg

[craig_colliass]

I have been busy sorting out the Omni Wheel robot platform for BB8 Project, as you can see the thing seems to be going OK.

it is great fun to drive even with the awful DX5e I have at the moment. enjoy the video.

[Niels - Team K.a.L.M.]

That looks cool... Way cool.

[suvv]

you should build a spinner around that and it would be brutal but i cant wait to see bb6 cruising round the pits

[daveimi]

That just seems to defy physics!

[craig_colliass]

Some pictures of the parts used in the omni wheel test chassis, just in case anyone wants to make one. I have had a lot of fun driving this mad bit of kit I would recommend it. setting up the mixer was not difficult either.


IMG_1098[1].jpg IMG_1099[1].jpg IMG_1100[1].jpgIMG_1102[1].jpg IMG_1103[1].jpg IMG_1097[2].jpg


I have chosen this as the main ball 500mm Polyethylene it weighs in at only 2Kg and is round! It has an access hole as it was a garden light fitting. The other picture is my attempt at making a mould for the manufacture of the access cover.



IMG_1116[1].jpg

IMG_1117[1].jpg