4WD

[Helloher]

Hello, I am considering making a 4WD for my second robot. I am a bit confused about this though. Do I need 4-channel radio gear, or do I just run 2 motors through 1 speedo?

[daliad100]

Re: 4WD

Unless you have some exotic drive train then you will only need two channels to drive.

You can run two motors off of one speed controller but I would check if the controller can take the extra load of another motor so you don't break it.

[Helloher]

Re: 4WD

Thanks. Are there any speedos I should avoid for a feather full body hammer If I do that?

[joey_picus]

Re: 4WD

Welcome to the forum first

As a general rule anything that's designed for remote control cars and is rated at aburdly high levels should be avoided, they'll just blow up. The Electronize controllers have a good reputation although you need at least two of them (one per side), while the Sabertooth 2x25A controls both sides in one unit and is quite good in my experience (I wouldn't use it on anything more powerful than drill motors though)

Everyone has their own recommendation though, based on their own experience, so it's best to ask

[Helloher]

Re: 4WD

Thanks Joey.
Can anybody who had particularly good experiences with a 4WD feather please reccomend me a speedo?

Edit: While I'm at it, I've got two more questions:
1) Can anybody recomend a 2-channel radio system?
2) Do feathers need gearboxes?

[psycho_fling]

Re: 4WD

most of us now use a radio system called spektrum these radios have some really good features and are as cheap as some fm stuff

they only come in a minimum of 3 channels, but those are pricey there are some 5 channel ones cheaper (would you believe)

you will need some kind of reduction gearbox on any motor

if you just want to practice and see if this is for you gor the cheaper option of 4 drill motors these have gear boxes attached you see

decide upon your motors then the contrller to go with them

alex

[Helloher]

Re: 4WD

Would you reccomend the spektrum for drills then?

Edit: Sorry for so many questions, I'm just so eager.

1) Would you reccomend the mtronics eco 27 speed controllers?
2) Where can I buy a safety link + LED?

[team_orr]

Re: 4WD

having good 4wd experiance id say, for your first bot, make a nice rectangular base, then get 4 drills from argos (£10 each or so) and mount themto your base. get some blue wheels from james or grant cooper and they just screw onto the drill shaft, then wire the two left motors up to each other, you should have two wires left over, do the same to the other side, buy a speed controller, id recomend tom wilkinsons speed controllers as they are very good and quite cheap, he isnt a big brand though so if he dosent have what you want the electronize speedos ( a different word for speedo is esc btw) ut you wil need 2, wire the wires from the drills into their respective esc/s (one es for each drill if its electronize, one esc for both if its a dual esc) and then plug the other wires coming from te esc into the reiciever. there should be a battery slot coming from the esc, plug your battery into there, well thats my area of knowledge :P ask around for other tips, we dont bite....mostly :P

[Helloher]

Re: 4WD

Thanks Jack, just one thing, where do I get the blue wheels? I know you said Grant Cooper, but is he a member here or something?

[team_orr]

Re: 4WD

yes he is
he and his brother james cooper run the full combat featherweight show robo challenge

james:

memberlist.php?mode=viewprofile&u=881

grant:

<a class=postlink-local href=http://www.fightingrobots.co.uk/foru...r /> <br /> oh

[john_frizell]

Re: 4WD

You asked:

1) Would you reccomend the mtronics eco 27 speed controllers?

No. With a 4 wheel drive machine you would need 4 of them, one per motor, because they can't handle much current. Even with 4 you might well overload them and for the price of 4 you could get more capable speed controllers. Also, they only go up to 12 volts so you can't over volt your motors which is a good way of getting extra speed and power. I used them once on a 2WD 8 kg feather and they worked for a while but were just not up to it.

2) Where can I buy a safety link + LED?

You can get a wide choice of LED's at Maplin. You can buy a link from Technobots or you can make one yourself. For feather links I use a loop of wire terminated in male bullet connectors with female ones inside the robot. Cost is about 10p if you have a pack of each kind on hand and you should because they are very useful for joining up things inside your bot.

Caome to an event and have a look at people's links - there are lots of ways to do it. I've sen one made out of a 13 amp mains plug.

[Helloher]

Re: 4WD

So you'll be at Reading? Will you be there on sunday?

Edit: Thanks John. That question was aimed at Jack.

[team_orr]

Re: 4WD

unfortunetly not, however, my friend dave weston will show you his robots and im sure other people will show you theirs if you ask nicey

[psycho_fling]

Re: 4WD

yeh the spektrum can be used with many different things including drill motors

http://robotbirds.com/catalog/product_i ... ts_id=1540

thats a dx6 with 6 channels i have 2 they are great and have decreased in price, trust me you will be glad of more channels you can also charge this one with the a wall charger and it has a good build qulaity feel

hope this helps
alex

[beast]

Re: 4WD

true for above but also try and get a BR6000 Receiver: not an AR6000 Receiver:

i did see a post about the 2.4 gig system for £30 (but has very limited bits no mixing etc but £30 )