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1  Using Arduino / Sensors / Re: Human detection, object avoidance, and other proximity help needed on: January 14, 2013, 07:36:40 am
The robots' head.  The robot will be in convention halls and seminars, so there will be a lot of people around it.
2  Using Arduino / Sensors / Human detection, object avoidance, and other proximity help needed on: January 12, 2013, 02:25:01 pm
OK, serious help needed.  When building a robot that needs to know where a human is with relation to itself, what is the best approach for recognition.  The end result is for the robot to turn its head to face the closest person.  I'm experimenting with either a single or dual ATMega 2560 platform, I'm not sure if I need two MCU's or not, there's going to be a lot to process.  I am also using a PCA9685 to allow for more PWM channels. 

Option 1: 4 fixed Sonar sensors on the neck (front back left right), 1 on the head, about $50 per sensor.  Neck detection will cause the head to turn that direction (stepper or encoder) and stop when it reaches the object, then do a centering on the lowest value (shortest distance).

Option 2: thermal detection, very expensive @ ~$100 per sensor, same approach, except more accurate due to the sensor being tuned to the same heat signature that the average human puts off.

Option 3: any variation or idea I haven't thought of yet? maybe sonar on the neck, thermal on the head?  I have even thought of using some mics to detect timing differences, but this will only work if the person is talking to the robot, I also want to be "creepy", if someone is sneaking up from behind, turn, face them, and play a sound file.

As a second objective, I need the robot to also have collision avoidance, with everything, including possible stairs or curbs.  The second objective can utilize other methods of detection, these sensors will be on the bumpers, so I'm looking at PIR or sonar only for that. two sensors, front and back, possibly tilted as to create a 3-6' range on the floor, giving the robot time to stop if moving full speed.

I want to accomplish this with the lowest cost possible.  I know this is an expensive task to accomplish completely, but hopefully someone can help me save a few bucks at the least.
3  Development / Other Hardware Development / Re: 5V supply help needed on: October 22, 2012, 09:54:38 pm
So I've found the battery, but I'm still a little confused on how to hook up teh charge circuit when building a pack.  Do I only need one MCP73843? Or is that all together teh wrong IC for this?
4  Development / Other Hardware Development / Re: Eagle assistance on: October 20, 2012, 09:25:25 pm
I was out of town all day, I have replied to both of you guys, thanks a bunch!  I'm looking forward to getting this taken care of.
5  Development / Other Hardware Development / Re: Eagle assistance on: October 20, 2012, 10:03:58 am
i'm still waiting for confirmation but if you can offer assistance I'll still accept it
6  Development / Other Hardware Development / Re: Eagle assistance on: October 19, 2012, 08:30:01 pm
done, thanks!
7  Development / Other Hardware Development / Re: Eagle assistance on: October 19, 2012, 07:29:53 pm
I have a circuit with 2 ftdi chips, an atmega328, and a usb hub, along with some pfet switching and other elements.  The pad2pad version is complete, it's just going to take me some time to figure out how to get eagle to link the pins, find the right libraries, etc.  It's definitely something I can do, but I'd rather it be done sooner, if possible for low to no cost.
8  Development / Other Hardware Development / Eagle assistance on: October 19, 2012, 06:49:27 pm
not sure if this is the right place to ask this, but is anyone willing to draw pcb's in eagle for free or low cost.  I used pad2pad originally but now have found out that the people running that software aren't exactly the cheapest.  The project isn't crazy complex, just very time consuming, so if someone who is more fluent in eagle could help me out, I'd really appreciate it.
9  Development / Other Hardware Development / Re: 5V supply help needed on: October 18, 2012, 08:19:56 pm
Found it, I'm bad at all the mumbo jumbo, but these are made for pack building, I just need to design a charge circuit

http://www.batteryjunction.com/tenergy-18650-tab-2600.html
http://www.tenergy.com/30005

I'm guessing I still need a protection circuit for each cell though right?
10  Development / Other Hardware Development / Re: 5V supply help needed on: October 18, 2012, 06:41:16 am
Cycle, that's what I have, if you scroll up I explained my reasons for wanting my own circuit.  Jack thanks for the help.  I'll keep an eye out to see what else I can find, I'm hoping for a single cell or dual at most, but that's almost impossible.  If only nimh or nicad were as light and had the capacity of lithium ;D
11  Development / Other Hardware Development / Re: 5V supply help needed on: October 17, 2012, 05:41:55 pm
So just to make sure I'm understanding this, if I use something like this:
https://www.sparkfun.com/products/8483

and hook up say, 10 of them, in parallel, then a single charge circuit would be sufficient?  I'm also looking at several of the 18650 style batteries, quite a capacity to reach, I'm trying to get around 20AH at a minimum, but reaching the goal would be even better.
12  Development / Other Hardware Development / Re: 5V supply help needed on: October 16, 2012, 09:21:52 pm
DOH, i definitely missed that, well, at least I've found "pack friendly" 2.6AH in the same size.
13  Development / Other Hardware Development / Re: 5V supply help needed on: October 16, 2012, 09:08:12 pm
So I'm thinking in the first wave of searching, 8 of these should meet those requirements.  Hooked up in parallel should give me 24AH.
http://www.batteryjunction.com/ultrafire-brc-18650.html

I'm still looking for smaller or flatter, but those are a good first round pick i think.

14  Development / Other Hardware Development / Re: 5V supply help needed on: October 16, 2012, 08:42:10 pm
Thanks for adding that up for me.  I'll start digging more in depth, I'll post what I find.
15  Development / Other Hardware Development / Re: 5V supply help needed on: October 16, 2012, 07:14:35 pm
ok, so I tested most of my parts, used datasheets for the rest, if everything pulls peak power its close to 1950mA, but not everything will be at peak at the same time, if ever, closer "run values" are more like 1400, if the main processor stays running full steam and everything else settles.
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