Let's Make Robots!

Interfacing two arduinos in the same robot

I'm wondering if I can make two arduinos interface with each other i.e. one for the servos and another one for sensor reading and receiving commands by RF (no need for tx-rx). Sorta like a master and slave thing. I would just want actually to make variables that both arduinos can read and write. Is it possible by hooking the tx rx pins together?

Thanks

Momentary push button to on/off switch?

Is there some way to make an on/off switch using a momentary push button? I think the buttons feel more natural. They are smaller too. Just wonderin'...

Measuring voltage with an Arduino

I was wondering if I could measure battery voltage simply by hooking the battery's + to an analog Arduino pin so that my robot can know when it's low on power. From what i've understood, a battery of 1.5 volts is dead when it outputs 1.4 volts (gonna do some research about this). I guess I can apply this approximation to different voltages battery. The only problem is that, if I want to use a battery with voltage superior to 5v (Arduino analog pins set 5v as a maximum), how do I divide the voltage? Again, I guess I'll need op-amps to do that and voltage dividers, but what do I exactly do?

Lead-free solder?

Is it worth to buy lead-free solder? It looks like a good idea at first, but then you realise that lead never reaches its evaporating temperature while soldering... Is that actually true? Some people say that the toxic fumes come from the flux and rosin and other stuff, but not from lead. Other sources complain about lead-free solder being more difficult to work with than normal solder. Any recommandations/personal experience with lead-free solder? I also want to ask if I really need to open a window while soldering (I don't have vents in the room I will be soldering).

Using an RF receiver/transceiver pair along with a wireless camera to process the images and send commands to a mobile robot

I would like to create a setup I will be using for a lot of my upcoming robots. A small wireless camera that will be ultimately outputting through USB to my computer. The computer processes the video and sends commands to the robot via RF. I guess the serial connection will be no more than 1900 bds. How can I coordinate RF and image-processing in a single program for autonomous navigation/other tasks (I can almost hear GroG saying "MyRobotLab" ;)?

Studying and working in the field of robotics

I'm in high-school now and I'm considering to study robotics and have a career in robotics. I guess it's what I'd like to do the most. What college programs and university programs should I take? What are the different career options in robotics? I think OddBot works for DAGU and I heard him say he loves his job (I never doubted he would, either). So how is your job like, OddBot? Any recommendations?

Great thanks to the whole LMR community

Selling: Mindstorms NXT 1st generation

I am disparingly seeking money to buy parts to dive into the world of hobby robotics. I'll need some 400$ for my first order and I decided to sell just about anything I can. So here goes my NXT... Anyone interested? I'll post details and stuff if someone's interested.

Robotshop Review

Is RobotShop a good place to buy parts from? I've heard they pissed fritsl off... Is it worth to buy things there? Are there any better online shops?

Wireless camera advice

I would like to implement a camera in my upcoming robots and I was wondering what is the best small camera on the market. For now, I think this one is good enough, but it still seems a tiny bit too big: http://www.robotshop.com/ca/draganfly-eyecam-video-system.html. Is this camera worth the money (I`ll probably use it if it is) or are there better/smaller ones?

Home-base recharging

I have been brainstorming and learning a lot since the last ... err... 5 months or so and I have come up with a lot of ideas. However, I thought that, in order for a robot to be completely autonomous, the robot has to be able to recharge itself and I was wondering how I would be able to implement this ``home-base charger`` the robot can find within a reasonable range. I`m guessing I should somehow use infrared but I`m not sure. Any ideas? Anyone?