2010 Kit

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KIPR Matthew
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We are currently working to create the 2010 kit. What input do you guys have for the kit (things to add, remove, change, things you liked, etc.)?

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mcsoccer11
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More Servos and Motors

tmac721
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Three words:

SILVER GEAR MOTOR

KIPR Matthew
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@ msoccer11: How many more?

@ tmac721: What is this silver gear motor you speak of?

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tmac721
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In 2007, the kit included a very high-speed, low-torque, silver motor:

https://botballstore.org/content/botball-silver-motor

mcsoccer11
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4 Black Gear Motors and 5 Servos

Also the break-beam sensor has been stated in the IC documentation for about the last 4 years but never given to us, that would be nice to finally try.

KIPR Matthew
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I'll look into adding more motors and maybe a silver motor. We have not used the silver motor lately because the motor LEGO interaction gave up problems, but we'll see.

The encoders or break beam sensors are not very nice. They require lots of shielding and have a limit on how fast they can read. I will look and see if there are any nicer ones out in the market that we could use, but with the very nice Back EMF, the uses have become limited. Originally they were for use on the handy board as motor encoders. This is how it would be used:

http://en.wikipedia.org/wiki/Rotary_encoder

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matthewbot
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I'd be interested in encoders. BEMF slips a lot over time, whereas a good encoder setup seems like it shouldn't. I mean, theres always wheel slip and the like, but its definitely compounded by BEMF slip. Just taking a motor and spinning it back and forth with your hand can eventually cause the counters to drift, especially if the motor is powered.

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JeffChan
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I second for the encoders!

Jeff

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matthewbot
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Oh and another thing, the white motors were definitely cheap and not really great driving motors, but it was still nice to have the quantity of motors for small random tasks. Its definitely situational but I think we'd rather trade the extra black motor back in for the four white motors we had last year. (Unless there were cost savings in there too, in which case keep it like it is, because...)

Legos. Need more. I think for our team at least this would be our #1 fix. Legos seem like they've been decreasing every year we've done Botball, and every year we just end up building smaller and (mechanically) simpler robots. I'll have to ask my hardware guys again, but I remember them thinking that the distribution of parts this year was better than last, but we'd really hope that the downward trend stops here. I guess in real engineering you'd be limited on supplies too, but Botball gets a lot less fun when the part bins are basically empty and you're trying to figure out which things on the robot's structure can be made weaker and use less parts while still working...

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Jeremy Rand
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In my experience, BEMF drift is often caused by noisy motor wiring or poor programming of the controller, rather than an inherent problem with BEMF. The Botball motors are much noisier than the Lego gray motors. I think purchasing better motors would be a better fix than trying to add the mechanical complexity of encoders. Also, the BEMF functions (especially Freeze) in IC were very poorly designed (and I suspect the CBOB is minimally better). If you want to see what proper motors and proper programming can do with BEMF, look at this video from Charmed Labs: http://www.charmedlabs.com/index.php?option=com_docman&task=doc_details&...

There is absolutely no drift there, even though the motors are being stalled a lot and are also being frozen for extended periods of time (which are usually the two situations in Botball that cause BEMF drift).

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