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Exciting new happenings at ServoCity in 2014!

We’re excited for 2014 because we have a lot planned!  Below we listed the Top 14 happenings we’re enthusiastic about in no particular order.

PID Tutorials for Line Following

Hey there guys. This post is outdated. Visit http://letsmakerobots.com/node/39972 for the updated tutorial.

Hello LMRians,

In this writeup, I will try to create a tutorial for tuning your robot using PID to follow a line. This tutorial won't go deep down into the details of PID and its applications but will just attempt to show how a robot can be tuned with the PID parameters to follow a line.

12V-30V Arduino Power Supply

So one project that I've been working on lately is a 24V Brushed Motor Controller Shield for Arduino. One of the features that the shield must implement is a power supply capable of power the Arduino with more than 15V, activates the Arduino when the input voltage is greater than 12V, and power any necessary gate driver circuitry. I finished Rev 1 of the power supply and plan to add one more revision to the power supply circuit before designing the reminding parts of the shield. 

Simple Camera Pan & Tilt

I wanted to create an unlimited 360° +/- pan with 180° tilt sync'd to my camera shutter (Prism)


So I got some scraps from the garage and made this thing - I know the quality is really lousy

I'm somewhat unsure if the fuel tubing couplers will be strong enough (bottom/pan coupler isn't connected yet)

Both mechanisms move "fairly freely" so . . . we shall see

 

It's a start - more later

:)

 

$500 ServoCity Scholarship - 2014 application now open

At ServoCity we care about helping students pursue their dreams - that’s why we’ve decided to offer this scholarship. We believe it’s important to encourage young minds to explore their potential and we hope this scholarship will aid a student in doing so. If you know of a high school senior who would qualify, please pass this information on.

The biggest moments in life..

Hi Guys,

I just figured I’d share this moment with you. The picture was taken just after my wife had been given birth to our second daughter a couple of days ago, December the 22. Guess I’m not much of a planner ;) But hey, at least it was not on Christmas eve!

Thank you for the greetings I have received by mail - as always, it’s amazing to feel your friendship :)

 

Bottoo or is that Bottwo ?

Well..  I'm just starting out on my second Robot.   I learned a lot about what to do, and more specifically what NOT to do while working on Robbie.

 

This new one will of course be based on the premise of Robbie, Raspberry Pi making the decisions, planning. mapping, etc.. with Arduino's doing the mundane work of running motors, reading encoders. 

Royal AP8000 8000mAh USB battery for $12 !!!

I just visited one of Costco's Clearance Outlet stores nearby, and found this LiPo battery pack for $12!  Just because it was out of it's packaging!

5v 2.1A out, wich charge level meter on front panel.  Weighs about 12oz...

Had to buy two of them  IMMEDIATELY before someone came to their senses!

It retails at Costco for $40, which is still a great price for LiPo  8000mAh here in Canada. 

Demo of a Conversational Robot that Learns by Listening...

I have been working on this for the past few months, basically, its a conversational learning AI.  I've tried to figure out how to explain it...best to watch the video.  The logic based stuff is a few minutes into the video.

At the core of it, the bot learns concepts by listening to people and remembering what they say...

28BYJ-48 Stepper pushes 2.8Kgs

As part of a 3D printed actuator , i have been sourcing parts for the drive motor...

Per-chance a 28BYJ-48 stepper motor shouted off the shelf .......

A few "Blender" iterations later ... a wormscrew and wormscrew nut were printed.

Hot off the press testing , just by holding the motor and nut secure ... i drove the stepper until it stopped.

As you see below it easily exerts a press force circa 2.3Kgs  .. the stepper locked itself at 2.8Kgs.

This force is being held on just two rows of thread - so good proof of PLA plastic stability.

Looking for ideas on a I2C Pan/tilt stand-alone sonar

This quest to build a stand-alone I2C pan/tilt range finder controller started with an article here by Ladvien.  In    http://letsmakerobots.com/node/39130, Ladvien explores using an ATtiny85 (84) as an I2C motor controller...

And in http://letsmakerobots.com/node/39222,   Chris the Carpenter   gives us an awesome pan and tilt code example... so...

Droid Planning

Firstly Thanks to Oddbot, Pome & the Dagu team for this amazing Robot.

Assembly time was about 16 hours, that included rebuilding the right wrist to get the servo in a position to be able to pour a liquid ;-)

SparkFun launches robotic parts & "Robotics 101" video series

Actobotics Logo - page

December 20, 2013: SparkFun launches the Actobotics robotic components online.

The first video shows Robert from SparkFun introducing the product line and talking about the various items.

"Do not average your Max-Sonar results..ever!" who knew?

I've apparently been mistreating my MaxSonar EZ-1.   I can't find where i stole.. er... borrowed my idea from for averaging a series of responses to reduce the inconsistencies, but I was looking up some information on the Arduino pulseIN() timeout (Thanks Oddbot!) and came across http://playground.arduino.cc/Main/MaxSonar   ... Yeah... I know it should have been one of my first places to look, but...

Sid, the clumsy housekeeper

You know I bought a Service Droid from Dagu, right? I wrote about assembling the kit here: http://letsmakerobots.com/node/39518

December 15, 2013.

Desk Robot; An attempt at planning.

 Yet to be named desk robot                                                                                                                                             

An Arduino that runs Windows or Linux, or almost any other OS

The Arduino has done wonders to bring embedded systems in reach of people who otherwise wouldn't have access to them.  It is a very powerful system, but it has drawbacks and limitations.  The program and data sizes are limited, as is the execution speed.  They are often plenty for many projects, but sometimes more is needed.  For larger projects more space is needed.  Or maybe it needs to be faster.  Also, you only have one program and to have the processor do more than one thing (multitask) requires some tricky programming.

Two Arduino problems fixed in one day! Halelujah!

 I've been procrastinating on two problems that I've not been able to resolve  - or google an answer for in my code.

 

1) Slow response in the Serial.parseInt() function... yes google gave me lots of people with the same problem, but I finally found a reference to  Serial.setTimeout()  ... well what do you know...  I set Serial.setTimeout(50)  in my setup... and low and behold...

  SNAP RESPONSE now!!!!   

 

Breaking Point (100% YAY)

Three part encapsulated "Blind" single print 3.5 cm  Linear Actuator ....destined for a 9g servo.

Will it break where i want it to .... in theory it will but practice will tell.....  stay tuned........

Inner Blue is the destructive part which will separate the slider in the tube.......

Wish me luck.....

Update :-

Endless hours of correcting  manifold  errors...double /triple vertex errors ... overhangs ...  etcetc...

Congress Talks about "Trash Robotic Router Platform". My personal project.

I wolud like to share with you, two talks that I have made this year in two national security congresses.

In both talks I present a Router based ROV [Texas Ranger] and a Fonera quadcopter [Atropos] both presented in LMR already:

http://letsmakerobots.com/node/23417

http://letsmakerobots.com/node/28143

The aim of "Trash Robotic Router Platform" is pretty the same of many members of this site. Use all you can get lying around in your home!

 

 

Finally got a "live" Sonar screen in HTML5 canvas / Javascript working

Prefacing everything i do with "I AM NOT A PROGRAMMER"...

Ok, so it's nowhere near perfect, but I thought I would post the code here in case anyone else wanted to tinker.

Web Control page for Autonomous Rover

 

The sonar.php  file which displays the instrument expects it's data as a JSON encoded data set in the form of:

{"ardtime":"43942","pan":"25","radius":"117","heading":"38.6"}

Review: The Service Droid kit from Dagu

I have received my Service Droid kit along with the Rover 5 robot chassis on a Monday evening. Excited, I opened up the package to reveal 2 big boxes, one with the Rover 5 and the other with the actual SD kit. The base comes assembled, with a battery box, a screwdriver (with a magnetized Phillips end), an Allen key (hex wrench) and a little bag with silicone lubricant. The droid kit comes with lots of parts grouped in separate labeled bags for easier assembly. To do the assembly, I used a cutter, a plier and the screwdriver from the Rover 5 box.

Read GCODE and parse CoOrdinates

So my polargraph had come to a halt, i had it running a processing sketch on a pc, and extracting shade data from images one pixel at a time. it had some cooool effects, im really happy with it but its time to move on.

I found i can convert a line/vector drawing to GCode in Inkscape, and as GCode is pretty much THE standard for opensource CNC it seems like the logical thing to use!

As before, this is a project for myself so im CERTAIN i havent gone about this the most effecient way (using a pre existing sketch would be the easiest option!) but its a learning process!

Bunniduino®

Today I found this in a local Carrefour store in Qingdao for 70 RMB. It has two RGB LED's which illuminate the ears and a couple of buttons. When certain buttons are pressed, it plays some songs or speaks some text (in Chinese).

I will probably hack it and build an emotional/chat robot out of it. In a first step I will take it apart and see what's inside (if my daughter let me...)