which speed controllers are better

I've been mainly looking at 2 different 1s the electronize FR30HX http://www.electronize.co.uk/model_elec ... frames.htm and the botbitz ESCheap85 http://www.botbitz.com/ , it roughly works out about the same in cost but the botbitz will probably have the import tax and VAT added on top also not sure weather the botbitz controller are rated at peak or cont

dose anyone have any bad thing to say about the botbitz ESCheap85 as i haven't heard much on the forum about them but i have herd some of the problems people have had with electronize

The botbitz controllers offer a lot more control/accuracy over the electronizes. Personally think its down to the fact they have a brake-type function. I never had any tax issues with them either

i hope botbitz are good.
they handle much more current.
they're both trusted escs though,
pointless post but I'm on a coach to Alton towers and I'm bored.

From my experience import tax only applies to products that could be sold for profit and are shipped in bulk. So buying 2 esc's is fine but if you ordered say 20 then you would probably get taxed.

My flat mates ordered some servos from japan, one ordered 4 the other ordered 30. The order for 30 got taxed and the others didn't so there is another example.

I would go with the Botbitz ones. I use electronize but they are really twitchy and slow to respond on occasion so the sooner they die the better.

Anything over £50 is due tax by the taxman. If you get the guys in australia to put toy robot parts in the customs decleration then you will likely avoid it as I believe toys can slip through the net

I've found 'gift' works even better than 'toys', though suppliers may be less willing to put that.

Quote:

---

All other goods
If you order or send purchased goods other than alcohol, tobacco, perfume and toilet water from a country outside the EU then you:
-don't have to pay Excise Duty
-may have to pay Customs Duty on goods with a value that exceeds £135
-will have to pay import VAT on goods with a value that exceeds £15
Note that on all goods from outside the EU, Customs Duty is waived if the amount of duty calculated is £9 or under.

---

Beyond me why you'd want to import 'toilet water'...

Quote:

---

Originally Posted by ewan

Beyond me why you'd want to import 'toilet water'...

---

Eau de Toilette (literal translation is water of toilet) is a lightly scented perfume used as a skin freshener.

ok thanks i'm thinking of using them in my 4x4 robot as I've just bought 4 ryobi drill to replace the Argos 1s and the ryobi 1s work out slightly cheaper for the 4 so i think i will stick with them for my robots now

Think im the only person using the bot bitz esc's in the uk so far...

I dont like electronize, there good for beginners, but there control is pretty lame... due to being relay based.

The bot bitz are good for a cheapo solid state esc, Only problems are;

A) Super slow speed control isnt that great.... but when do you ever drive a robot at less then 1/8th throttle? - its kind of a non issue...

B) You cant turn the brake function of to my knowledge... but i like having the break function.

C) When you initialy power up the esc- as with any brushless esc it pulses the motor.. meaning the drive wheel attached will roll forwards and back a small amount, not enough to really move the robot...more to make it just shake... i took a video showing this, its on my youtube page...

Anyhow, i personaly see A.B and C as non issues, and id go with them any day over electronize.... i ordered 2 more last week, ill let you know if i get taxed... i dont think i did on the first set.

http://www.youtube.com/watch?v=7BODQ0bt ... ature=plcp

The in-built breaking would cause problems for a robot, would it not? E.g., drills often favour one direction over another a tiny bit (at least in my experience), meaning the robot never drives quite straight until you fiddle with trims. The problem I had with Tormenta was that, one side of the drive would stop before the other, meaning I oversteer or just the steering in general is a bit funky, unless I keep the power on and drive more binary-style. It made driving slowly in a straight line almost impossible.

With breaking I can see that characteristic might be worse. If you're turning in a wide arc, once you come off the power the inside motors will break a little sooner than the other side, spinning you round in that direction, right? I can see that actually not aiding the driver, but making things worse, if anything?

I am really very tempted by these ESCs, though the Electronize have done us well and after 2 years they're still good as new. If they're not going to be perfect, though, I can't justify the money, even if they are remarkably cheap.

@Ellis,
The breaking on one side and not the other you're experiencing with the Electronizes is a feature I've experienced and I believe it's down to the Relays.
On Bitza sometimes when the stick centralises on the Tx it'll swap the motor direction (the relay clicks over), which feels like breaking, only it would only do it on one side.
Why? I don't know, annoying? Yes!

Electronic breaking is good for control, but it'll make your ESCs work hard.

@Dave,

Ah the bedroom workshop, we've all been there.

While we're on the subject of 'Which ESC' I bought a couple of super cheap Chinese ESCs the other day.

£13 each on recommendation from Guileherme, can take up to 14v (18v with a simple mod) and he runs 2 drills on one so plenty of amperage.
Built in BEC, Li-Po prtection etc... Came in just a few days.

I do have an issue though where there is a major delay between fwd and rev if anyone has any insight into why?
Guileherme hasn't experienced this with his.

PJ- it's warmer then the shed lol...

Ellis, I think if you got them you'd find tormenta drives much better... Electronizes are ghetto. Fact.

Lmfao, the robot was made out of wheelbarrow inner-tube and chopping boards, ghetto iz how we do. :wink:

I'll be testing a couple of the Botbitz 25A ESCs in the next couple of weeks on 4 drill motors at 12v, testing them using Cicatrix so will post the results on here soon.

That would be great. Keep us posted. If they work well, they're much closer to reality money-wise for us. We'd be running the drills hard and at 18v, though.

I don't have an 18v battery or any combination of batteries that could produce 18v :( . I was tempted to try them on 19.2v that I run Cicatrix on normally as the XXL can behave a bit strangely sometimes and they would be a nice cheap replacement for it, but they're only rated at 18v. I'll do the 12v test first so I don't kill them then do a 19.2v test if i'm feeling brave.

could you use one of these?
http://www.google.co.uk/search?hl=en&gl ... WPzE&mvs=0
wow that's some link.
if you build it into a circuit but they.don't handle that many amps.

When someone told me about people hacking brushless esc's to drive brushed motors I was a bit confused since Castle Creations and Novak 1:8th scale and 1:10th scale ESC's can do that already without any modifications (and probably Tekin ESC's as well but I am not certain about that one).

I believe the hack is mostly (if not entirely) changing the firmware on the ESC, physically a brushless ESC is capable of controlling a brushed motor so some companies built in the ability to do both.

i know this isn't quite related but i was just wandering if anyone else finds the 50a blue speed controllers a bit twitchy or is it just that 1 of mine might be naff

they are not the best controllers in the world, plus 2 single controllers are often more twitchy etc compared to a dual speedo

i even tried hooking a gyro up and and it kept turning left a bit then right a bit about 2 to 5 times then stopped so i took that out

the other thing that i wandered might be the problem is the v tail mixer, its the same one on the giant shark website

Quote:

---

Originally Posted by mr_turbulence

Think im the only person using the bot bitz esc's in the uk so far...

I dont like electronize, there good for beginners, but there control is pretty lame... due to being relay based.

The bot bitz are good for a cheapo solid state esc, Only problems are;

A) Super slow speed control isnt that great.... but when do you ever drive a robot at less then 1/8th throttle? - its kind of a non issue...

B) You cant turn the brake function of to my knowledge... but i like having the break function.

C) When you initialy power up the esc- as with any brushless esc it pulses the motor.. meaning the drive wheel attached will roll forwards and back a small amount, not enough to really move the robot...more to make it just shake... i took a video showing this, its on my youtube page...

Anyhow, i personaly see A.B and C as non issues, and id go with them any day over electronize.... i ordered 2 more last week, ill let you know if i get taxed... i dont think i did on the first set.

http://www.youtube.com/watch?v=7BODQ0bt ... ature=plcp

---

A - What issues do you find down low? Does it take more stick then you expect to make the robot move? Have a chat to Steve (Marto) on the RoboWars forum, he can probably look at changing the code to make the controllers more responsive to your requirements. I believe at the moment the controllers have a decent size dead band to be more compatible with cheaper radios like the HK TX4A's, so this might also be apart of what your seeing. From my testing, the ESCheap85's were a lot nicer to drive then when I was using Victor883's, but not as nice as my IBC (I loved that controller :( )

B - Correct, there was originally a programming method built into the controllers by doing stick and beep codes like most brushless controllers, but we were a little worried about people entering programming mode during a battle (caused by power resets) so it was removed. Pretty much everyone we've ever spoken to has preferred braking enabled. If you would like a custom set without it, we can do that.

C - As apart of the programming method, Steve introduced the motor beeping code. When the programming idea was scrapped, he left the beeping code in the firmware to provide another method to alert builders that a robot is powered on. I believe this may have been removed from recent firmware changes as well, I will have to have a chat with Steve about it.

Any other comments or feedback, throw them up on the Botbitz thread on the RoboWars forum, or check out our facebook page (http://www.facebook.com/botbitz/). We're happy to make changes to suit peoples requirements.

I've found another option from china

http://www.ebay.co.uk/itm/T2000-Dual-Mo ... 3610wt_922

I always smile when I see 75A continuous and 160A peak in the specs, and a Tamiya plug on the battery lead. :)

Tried to test the botbitz controllers today on 9.2v with 2 12v drill motors attached but one of them doesn't seem to be working :( . I'll have another look at my soldering and see if its that, but it looked ok when I did it. Don't really want to have to send them all the way back to Auz to get looked at :?

FYI - my second pair of botbitz tz85's arrived today... no customs charge :)

antazz - tried a higher voltage?

Leo- alot of brushed/brushless escs on the market such as the mamba monster max etc seem to have a delay between forward/reverse of 2 seconds or so.... so not really ideal for drive in robots.

speaking of botbitz, just seen their new motors, looking quite good atm. bigger shaft would be good.

Quote:

---

Originally Posted by mr_turbulence

antazz - tried a higher voltage?

---

First free day i'll have is tomorrow since I saw this, I will try then.

Quote:

---

Originally Posted by knightrous

Shoot an email to sales@botbitz.com , we'll work through troubleshooting it with you

---

Will do, thanks:)

Did the higher voltage work?

Haven't had the chance to test it yet, been working constantly since starting a new job. I'll try to get it done very soon. At the moment my next day off is on tuesday, so i'll try it then and get back to everyone.

Quote:

---

Originally Posted by Anttazz

Haven't had the chance to test it yet, been working constantly since starting a new job. I'll try to get it done very soon. At the moment my next day off is on tuesday, so i'll try it then and get back to everyone.

---

That would be great. We're at the stage with Tormenta 2 where we either need another Electronize 30a or for a similar price get 2 of the 25a BotBitz. Having just done a test drive the precision (or lack of) with the Electronize is an issue.

If your after better control why not invest in a dual speedo ?

In my time making robots I have had:-

Sidewinders.
Electronize 30 amp.
Wotty 360, 180 and 100s.
Sabertooth 12 and 25 amp.
Victor 883.
and some cheap blue E bay stuff!

For cheap go for E bay expect problems, :uhoh:

Electronize and Victors are very good strong speed controllers they can lack finesse but this is war! they are single channel and so you may find they work best in a 4 wheel drive setup.

For better control go for dual channel speed controllers, two drill motors or Gimson drives the 25amp is very good. I have the 12 amp with these motors in Gabriel. :shock:

For ultimate power in a feather go for a Wotty 100 or find a Sidewinder. :D these seem to take anything you give them Seraph has a Sidewinder and Tron has a Wotty 100.

Thanks for the help guys. We really can't afford to buy something flashy for this thing, we just don't have the money, so like everyone I suppose, I'm trying to find the cheapest option!

The 25a Sabertooth has crossed my mind more than once, but it's really over what we can pay, and I can't say I have heard 100% positive results when run with 2 drills each side. Can't afford to pay for something that won't be reliable and handle the needs, at least within sod's law.

The exact issue is that, one side seems to react far less if at all for up to around 25% throttle whilst the other does. But, it isn't consistent. Sometimes it's the other side that is delayed. And, it isn't just a little bit, it's very noticeable when driving. That, coupled with the time it takes for the relays to switch, makes it really not great. Turning at low speed with any precision is almost impossible. When racing around at near full throttle it's fine, though.

Of course, if anyone has a suitable ESC or ESCs (dual or not) up for grabs, we may well be interested. Thanks.

Could be the motors. Most drill motors have advanced magnets, so you get more power one way than the other.
Apply the same voltage to the motor either way and you'll hear the change in tone from the different RPM.

With the robot is on the it's cradle and powered up, by operating just the forward trim on the Tx do both sides move very slowly at the same setting? If not then swap the speed controllers over and try again, if the symptom changes the problem is with the speed controllers or the controls Tx Rx or wires, if the symptom stays on the same side it is the motors or transmission.

Are the wheels free to move are the motors stiff? If the robot has been in combat things get bent and this can cause problems.

Some motors are configured to work better in one direction than another, this is done by magnet position I don't think this is a problem for you at this time.

dose the problem only seem to occur when the motors are under load? so on the cradle it's ok but on the ground it causes problems. If so it is down to the power being delivered to the motors this could be the speedo is bust or the circuit resistance is for some reason too much.

The wire and plug connections can be a problem Tamiya plugs can cause problems I am getting rid of these on my robots also check for damaged insulation on wires also check soldered joints and avoid using screw connectors (choc blocks) as they can cause problems.

Keep trying different things and soon you can narrow the cause of the problem down. :D

Relay based controllers are best suited to slower EV's such as mobility scooters where fast forward / reverse is not required. ESC's using relays need to reduce motor current to a very low level before switching in order to avoid contact burning / pitting, which eventually results in unreliable operation. ESC's such as the Sabertooth which uses 'H' bridge solid state switching arrangement are far better suited to combat robotics where fast direction changes are needed. However, as these controllers switch with Mosfets, high voltage transients can easily damage an ESQ. Keeping motor and battery leads as short as possible and tightly twisting their respective wires together helps to avoid damage. Avoid using any type of screw type terminal to connect motor and battery to the ESC. Most importantly, follow the manufacturers guidelines on the loading of ESC's and keep within the recommended working voltage, not the absolute maximum working voltage, which is usually a fair bit higher.

Hoppy