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Re: Robo-Cross B
Posted: October 22nd, 2013, 7:19 am
by harryk
Current is completely separate from voltage(in a largely simplified view). A car battery only provides 12v but can provide a current up to several hundred amps, whereas a 9v battery will only provide roughly 500mA of current. Chances are your DC Adapter has an output rating labeled on it, and its likely less than 2A. You should look into getting a rechargeable battery pack for your robot. A NiMh or NiCd type battery pack should serve you well and provide plenty of current.
Re: Robo-Cross B
Posted: October 22nd, 2013, 2:08 pm
by DrunkWapiti
Am i allowed to have multiple controllers?
Re: Robo-Cross B
Posted: October 22nd, 2013, 3:17 pm
by jander14indoor
DrunkWapiti wrote:Am i allowed to have multiple controllers?
Usual caveat, this isn't an official clarification, just my opinion, just one of several who input to Robo-Cross clarifications, have to get official stuff from NSO website, etc...
Para 2.b says "The Robot may be controlled remotely by radio, infrared, or wired control boxes to the Robot. The Robot and Controller(s) are defined as the Device."
Just the way I read that sentence, the s's at the end of 'boxes' and 'Controller(s)' strongly imply that you are allowed to have multiple controllers.
Jeff Anderson
Livonia, MI
Re: Robo-Cross B
Posted: October 22nd, 2013, 3:37 pm
by UQOnyx
harryk wrote:Current is completely separate from voltage(in a largely simplified view). A car battery only provides 12v but can provide a current up to several hundred amps, whereas a 9v battery will only provide roughly 500mA of current. Chances are your DC Adapter has an output rating labeled on it, and its likely less than 2A. You should look into getting a rechargeable battery pack for your robot. A NiMh or NiCd type battery pack should serve you well and provide plenty of current.
Oh, thanks, that explains it. I thought it may be so because the output on the 9v battery says only 500 mA of current
EDIT: My battery is actually only 200 mA. Would I fry my reciever with a 1 Amp battery?
Re: Robo-Cross B
Posted: October 22nd, 2013, 4:33 pm
by iwonder
Umm, you have to watch out, that's why harryk and others suggested a y-harness so the current doesn't burn up the traces on your receiver.
Re: Robo-Cross B
Posted: October 22nd, 2013, 4:35 pm
by harryk
UQOnyx wrote:harryk wrote:Current is completely separate from voltage(in a largely simplified view). A car battery only provides 12v but can provide a current up to several hundred amps, whereas a 9v battery will only provide roughly 500mA of current. Chances are your DC Adapter has an output rating labeled on it, and its likely less than 2A. You should look into getting a rechargeable battery pack for your robot. A NiMh or NiCd type battery pack should serve you well and provide plenty of current.
Oh, thanks, that explains it. I thought it may be so because the output on the 9v battery says only 500 mA of current
EDIT: My battery is actually only 200 mA. Would I fry my reciever with a 1 Amp battery?
The labels on your batteries are not the max current, but in fact the amount of energy within the battery measured in Amp-hours(usually denoted as Ah or mAh. If your battery is labeled as 200 mAh, this means that it can provide a current of 200mA for the duration of an hour before running out, likewise the same battery could likely output 400mA for half an hour and so on. The max current is a measure of how much energy it can discharge at a given moment, and is limited only by the internal resistance of the battery.
Also, your receiver can probably handle a couple amps of current. It's hard to say for sure but most are rated for at 3A. Unless your using some heavy duty servos you shouldn't need to worry about overloading it. Though using a Y-harness is always a good safety measure incase of a short circuit.
Re: Robo-Cross B
Posted: October 24th, 2013, 3:20 pm
by akfackenthal00
In the last year that this even was in b div, did anyone watch the official scioly robocross video? if you know what im talking about, and you did, did you see the robot with the belt with magnets and stickytape on it? I would love to know the brand of the robot and the team that made that modification... thanks!
ps. sorry if this is kinda confusing
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Re: Robo-Cross B
Posted: October 25th, 2013, 4:10 pm
by UQOnyx
harryk wrote:UQOnyx wrote:harryk wrote:Current is completely separate from voltage(in a largely simplified view). A car battery only provides 12v but can provide a current up to several hundred amps, whereas a 9v battery will only provide roughly 500mA of current. Chances are your DC Adapter has an output rating labeled on it, and its likely less than 2A. You should look into getting a rechargeable battery pack for your robot. A NiMh or NiCd type battery pack should serve you well and provide plenty of current.
Oh, thanks, that explains it. I thought it may be so because the output on the 9v battery says only 500 mA of current
EDIT: My battery is actually only 200 mA. Would I fry my reciever with a 1 Amp battery?
The labels on your batteries are not the max current, but in fact the amount of energy within the battery measured in Amp-hours(usually denoted as Ah or mAh. If your battery is labeled as 200 mAh, this means that it can provide a current of 200mA for the duration of an hour before running out, likewise the same battery could likely output 400mA for half an hour and so on. The max current is a measure of how much energy it can discharge at a given moment, and is limited only by the internal resistance of the battery.
Also, your receiver can probably handle a couple amps of current. It's hard to say for sure but most are rated for at 3A. Unless your using some heavy duty servos you shouldn't need to worry about overloading it. Though using a Y-harness is always a good safety measure incase of a short circuit.
Thanks for the help
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. I found a 9V, 1 Amp output power adapter. I hooked it up, and so far, the weak arm and everything have stopped. Thanks again harry and iWonder. The robot arm is still struggling a little when it is loaded up too much, but probably a better battery would solve that as well. I also would recommend using an AC/DC power adapter when testing the device to everyone, because it doesn't need to be recharged, and so you don't have to worry about recharging or anything.
Re: Robo-Cross B
Posted: October 28th, 2013, 6:52 pm
by transcience
mrburrito wrote:transcience wrote:Can you use lego mindstorm for Robo Cross?
As long as there is at least one functional modification, you may.
What do you mean by functional modification?
Re: Robo-Cross B
Posted: October 29th, 2013, 3:54 pm
by UQOnyx
Functional modification is simply that you have to change at least one aspect of the device. If it is a lego or vex kit for example, you can not simply take take it out of the box, follow the exact instructions, and use it, you must change at least one part so that it is different from what you would find out of the box.