Arduino, Robots, Kits and Home Electronics Hobbies

Mixolyde wrote:

For anyone interested in electronics, MIT's online course program, MITx, is offering a beginner undergraduate course in Circuits and Electronics

How does MITx differ from OpenCourseWare? (Since there's a similar course on OCW).

It's a fully graded course, with staff support.

Arise thread!

Okay, I think I'll be needing some help in the coming weeks. When I told my wife to get me a beginner, no-solder robot kit that I could put together with my 10 y/o son, she sort of mis-understood. She ended up getting me the Jameco J-Bot kit. I've decided to keep it (as a challenge to myself) and now I have to brush off my soldering skills and learn to program an Arduino microcontroller board. I bought the Arduino Uno Rev 3 Starter Kit along with the book "Programming Arduino Getting Started with Sketches" by Simon Monk.

The J-Bot seems kind of cool. It's a 4WD mobile platform that comes with a sonar sensor to detect obstacles. I'm interested in what other gadgets I can throw on there, though that is definitely far down the line.

So does anyone have any advice for a complete Arduino newbie?

I've got a few Arduinos but I still haven't done much with them other than do the usual cylon lights and make some noises. But it's a great foundation made for ease of accessibility that sets you up to move on to programming Atmel chips in C if you so desire. I'd say you're already on the right track with that book and are probably best off just working with it for now so you don't overload yourself making it feel more overwhelming than it really is.

Nevin73 wrote:

Arise thread!

Okay, I think I'll be needing some help in the coming weeks. When I told my wife to get me a beginner, no-solder robot kit that I could put together with my 10 y/o son, she sort of mis-understood. She ended up getting me the Jameco J-Bot kit. I've decided to keep it (as a challenge to myself) and now I have to brush off my soldering skills and learn to program an Arduino microcontroller board.

I don't understand... It looks like that bot has a breadboard, so you shouldn't need to do soldering...

It looks like you solder leads to the motors and that's it. So yeah, hardly anything to be worried about.

NSMike wrote:
Nevin73 wrote:

Arise thread!

Okay, I think I'll be needing some help in the coming weeks. When I told my wife to get me a beginner, no-solder robot kit that I could put together with my 10 y/o son, she sort of mis-understood. She ended up getting me the Jameco J-Bot kit. I've decided to keep it (as a challenge to myself) and now I have to brush off my soldering skills and learn to program an Arduino microcontroller board.

I don't understand... It looks like that bot has a breadboard, so you shouldn't need to do soldering...

You need to do it on the Motor Shield (from the instructions that I was reading).

Link

We have a pool. Would that kit be able to avoid driving into the water autonomously?

duckilama wrote:

We have a pool. Would that kit be able to avoid driving into the water autonomously?

Usually sonar or IR sensors take the measurements they receive and transfer it into a voltage. In the programming, you set the voltages as commands, such as reverse when it gets to .7v etc. So you could do that but the speed of it would have to be slow and the sensor would be far enough ahead of the wheels to see the difference between the sensor and the normal path and then the larger depth of the sensor over the pool.

Another good tip when you are using motors -

Pololu[/url]]1) Solder capacitors across your motor terminals. Capacitors are usually the most effective way to suppress motor noise, and as such we recommend you always solder at least one capacitor across your motor terminals. Typically you will want to use anywhere from one to three 0.1 µF ceramic capacitors, soldered as close to the motor casing as possible. For applications that require bidirectional motor control, it is very important that you do not use polarized capacitors!

Probably be easier just to make the thing water proof.

I'll probably start digging into the kit this week. The Uno board is still en-route but I can start assembling the chassis.

The pool has a dark red brick "border" and the patio is near white. Maybe a light/color sensor thing.

Katy wrote:
Mixolyde wrote:

For anyone interested in electronics, MIT's online course program, MITx, is offering a beginner undergraduate course in Circuits and Electronics

How does MITx differ from OpenCourseWare? (Since there's a similar course on OCW).

Was MITx only offered for one or two semesters? I just heard about it here and it looks like it no longer exists in a graded form.

So just a quick update. I put together my J-Bot with the Arduino Uno board. It works (mostly). I think there is some fine tuning and tweaking that needs to be done in both the code and the electronics. Unfortunately I haven't had the time or drive to dive that deep into the tech.

I've discovered that the (more or less) same kit offered by DFRobot is superior to the J-Bot from Jameco. The instructions are better and it has more functionality.

What I came here to really talk about is Lego Mindstorms. Man, is this kit awesome. We gave it to my son (and to me) for Christmas this year. With clear directions, easy-to-assemble tech, and simple programming, I was able to recreate the J-Bot with my 10 y/o son in an hour. I've seen Youtube videos of people solving Rubik's Cubes with this kit. I'm floored by it. So far my son and I have built and programmed a marble-shooting guard robot, a color-detecting robot, and we are currently working on a RoboGator. While designing the mechanical body seems like it would take tremendous insight, the programing is incredibly easy to get started with. My son has already started programming movement commands and is starting to learn the age-old programming techniques of trial and error. I'm completely wowed by this and would recommend anyone looking to start off easy or to get their kid interested in such a hobby.

My son (he's 12) recommends http://www.nxtprograms.com/ for some additional design ideas.

One of his gifts this year was the Edge Robotic Arm kit. He spent all afternoon Christmas day assembling it. It seemed like a fun build.

I got an Arduino a couple of days ago along with the Side Kick kit. I finished my first project which is a clock with 2 buttons to adjust hours and minutes and 4 LEDs for the 4 digits. Each LED will blink the number of that digit. The hardest part was getting the hardware interrupt working with debouncing on the buttons.

Next up is playing with the servo and potentiometer.

IMAGE(http://i.imgur.com/RT9mhjK.jpg?1)

I got introduced to Arduino about a year ago when a friend of mine put an Arduino Mega 2560 and a bag of random components in my hands and told me to go play with them. Now I have two big cases filled to the brim with components and I'm completely hooked on it.

My latest project was a DIY version of a Tellstick to turn on and off my Nexa remote switches for lamps in the house. I currently use an Arduino Mini Pro along with a 433MHz transmitter and receiver.

The Arduino reads commands over serial, currently with an FTDI USB cable but I will be replacing it with an Arduino Nano with an on-board USB Mini port. Commands are in the form of: SET,remote_id,device_id,on/off

On the other side of the USB cable is my NAS that is running a python web service using the Flask framework (I'm originally a software guy so most of the heavy lifting went into the computer instead of the Arduino) that has two main parts:

The REST API, handling HTTP requests and translating them to serial commands. For example, going to http://fancy-nas-ip/api/123456/1/on will send SET,123456,1,1 over serial, which in turn lights up the window-lights in my livingroom.

The GUI, a simple list of named devices with on/off buttons next to them. Devices and remotes are stored in an SQLite database. The UI was laid out using Foundation so that it responds to screen sizes in a good way (usable UI on both the computer screen and on the phone). The buttons trigger JQuery to send HTTP requests to the REST API.

Triggering on/off through simple HTTP GET requests opened up some pretty cool possibilities using the Tasker app for Android. Combined with AutoVoice I can turn lights on or off with my voice, I could turn them on when I get close to home or connect to my home WIFI, and so on.

Right now the electronics are on a breadboard but once my new Nano arrives I will put it in a project box and replace the green wires with a proper antenna.

IMAGE(http://i.imgur.com/ZOwmpPa.jpg)

Looks cool, Papapishu. My wife got me an Arduino Starter Kit for Christmas, and blackanchor got me an Arduino Uno, so I'm going to start building something. Not sure what yet.

Probably going to figure out how to hook it up to my webcam and a Guitar Hero guitar and finally beat all those songs on Expert.

I actually built a quadcopter with Arduino control a month or so back. Turns out that PID control is a little more sophisticated than I'd realized. We built a quadcopter that could achieve stable flight, if by stable you mean, didn't crash and stayed within 30 feet of the starting point.

We only started playing around with Arduino with my 4 year old and he is hooked, even though not yet nimble enough to connect stuff to breadboard. However, he loves that we can make stuff work. Next stop: a simple robot.

Bonus_Eruptus wrote:

Probably going to figure out how to hook it up to my webcam and a Guitar Hero guitar and finally beat all those songs on Expert.

Sounds like a cool project, will you be processing the video stream on a PC and sending commands over serial to an arduino controlling servos? Without much knowledge in the subject, image processing sounds a bit too computational heavy for an arduino

kazooka wrote:

I actually built a quadcopter with Arduino control a month or so back. Turns out that PID control is a little more sophisticated than I'd realized. We built a quadcopter that could achieve stable flight, if by stable you mean, didn't crash and stayed within 30 feet of the starting point.

Quads are really cool, was it based on arducopter? PID controllers can be rough to implement, quite a while ago I took a course on Udacity called "Programming a robotic car" (CS373) with Professor Sebastian Thrun which had a great walkthrough on, amongst other things, PID.

Me and a friend was trying to build a quad using the PX4 Autopilot hardware on top of an AR.Drone frame, unfortunately we ran into some issues with a broken ESC for one of the motors. Tried replacing it and got other problems instead possibly due to ESC firmware version mismatch between the replacement and the rest.

For now it is just resting on a shelf, not sure what to do with it at the moment but it's sad that it never got any airtime.

wanderingtaoist wrote:

We only started playing around with Arduino with my 4 year old and he is hooked, even though not yet nimble enough to connect stuff to breadboard. However, he loves that we can make stuff work. Next stop: a simple robot.

It is so much fun to mess around with and integrating with toys can be even more fun. I did a small project with my 6 year old son where we had a dragon on top of a servo and a distance sensor triggering it to turn around and shake angrily if you got too close to a treasure chest.

papapishu wrote:
Bonus_Eruptus wrote:

Probably going to figure out how to hook it up to my webcam and a Guitar Hero guitar and finally beat all those songs on Expert.

Sounds like a cool project, will you be processing the video stream on a PC and sending commands over serial to an arduino controlling servos? Without much knowledge in the subject, image processing sounds a bit too computational heavy for an arduino :)

Probably not servos. Some of the projects I've seen use the camera at a low resolution, and use the colors of a few selected pixels on a few lines around what should be strummed shortly to determine which buttons to press. Then they just set the pins for which buttons should be pressed and send that signal on.

Here's one that pre-processes the video to generate note charts, so the game just sends signals at normal intervals. A few sites like ScoreHero used to have the note charts, like this, and I believe some in MID format, so you could probably hard-code them and just select the song with a pot and LCD or something.

I've also seen some fancier ones where they mod an Arduino into the guitar, but I can't find that link at the moment. Someone started a Kickstarter for one, though: GuitarZero

kazooka wrote:

I actually built a quadcopter with Arduino control a month or so back. Turns out that PID control is a little more sophisticated than I'd realized. We built a quadcopter that could achieve stable flight, if by stable you mean, didn't crash and stayed within 30 feet of the starting point.

Quads are really cool, was it based on arducopter? PID controllers can be rough to implement, quite a while ago I took a course on Udacity called "Programming a robotic car" (CS373) with Professor Sebastian Thrun which had a great walkthrough on, amongst other things, PID.

Me and a friend was trying to build a quad using the PX4 Autopilot hardware on top of an AR.Drone frame, unfortunately we ran into some issues with a broken ESC for one of the motors. Tried replacing it and got other problems instead possibly due to ESC firmware version mismatch between the replacement and the rest.

For now it is just resting on a shelf, not sure what to do with it at the moment but it's sad that it never got any airtime.

For the most part, based on programming it from scratch. We looked at arducopter, but we were building it for a class, and it looked a little too plug and play for a reasonable school project.

Shot in the dark on your ESC: did you make sure it was properly calibrated?

My son just finished building an adafruit Monochron clock kit. The example display program plays pong with itself.

And my husband used some of his break time to finish building their ice tube clock, which he'd gotten as a kit a few years ago.

So we have plenty of clocks.

We're extremely happy with Adafruit's customer service / technical support. They were very helpful in diagnosing the short which broke the LCD of the Monochron, and were quick to ship out a replacement.

edit: nevermind, dumb comment.

kazooka wrote:

Shot in the dark on your ESC: did you make sure it was properly calibrated?

Good point, I think I'll have to take the quad home again to see if I can manually calibrate the ESC.

Made the mistake of "saving a few dollars" by ordering just the AR.Drone shell with the frame and the motors but not the main board since we were to use the PX4FMU together with the PX4IOAR board in it instead. This seems to have been a very bad idea since it appears as though the ESCs have their own firmware and from what I've seen they are supposed to be upgraded through the main board.

I'd think we would have been much better off building our own like you did, it is easier to troubleshoot and fix issues if you put the parts together yourself

Recently got me an arduino starter kit but I'm surrounded by folks who have dabbled but stopped after the making LEDs blink example sketch. Currently in the middle of several projects, all of them basic data logging sensor stuff.

First is something for my team's kegerator at work. Currently measuring how much has been dispensed from a keg with a flow sensor. It's powered by a netduino and will soon be measuring co2 and beer keg levels, a badge reader and whatever else we can squeeze in next company hackathon.

Another project is a garduino/automated farm sensor and actuator system for a friends urban farm. Temp, humidity, soil moisture and light sensors are prototyped on a breadboard powered by an arduino uno. Next step is to figure out how to control irrigation.

Finally, helping out a brewer friend with his sensors. I've only walked him through some code but I'm hoping to get more involved in exchange for free beers.