Posts tagged "community projects" (Page 2)

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Zumo tennis ball collector

Posted by Jon on 2 June 2014

Forum user patman715 posted to the forum about his modified Zumo Robot. The video above shows a Zumo with a two-servo gripper and arm capable of lifting tennis balls into an on-board storage bin. It is all controlled by an Arduino Leonardo, and two of our 100:1 micro metal gearmotors (we suspect they are HP versions) seem to give it plenty of oomph for carrying around the extra load.

Custom optical encoder signal processing board for the Zumo

Posted by Jon on 16 May 2014

Erich, a professor at the Lucerne University of Applied Sciences and Arts in Switzerland, posted to our forum about a circuit he designed for the robots he’s building based on our Zumo chassis for his embedded system programming course. His Zumos are retrofitted with our micro metal gearmotors with extended backshafts and optical encoder board. The custom circuit he designed converts the analog output of our optical encoder boards to digital waveforms, which makes them more easily interpreted by microcontrollers and other devices. His board uses a Digital-to-Analog Converter (Microchip’s MCP4728) and four op-amps (Microchip MCP6004) to generate the modified quadrature output. The DAC can be controlled directly over I²C and can be calibrated automatically. After verifying that it works, Eric ordered a bunch more boards to use in his course:

One of Erich’s fully soldered optical encoder boards with attached 3-tooth wheel.
This oscilloscope capture compares the processed encoder output (top) with the raw output voltages of the optical encoder board (bottom).
A bunch of signal processing PCBs!
Erich’s optical encoder signal processing board with components populated.

We look forward to seeing how they work with the Zumos!

You can read more about Erich’s signal processing boards on this blog post from his website. You can follow the progression of the robots used in his course by visiting these forum posts:

March 2013: Zumo Robot with FRDM-KL25Z Board

September 2013: Zumo Robot with Pololu Plug-in Modules

October 2013: Zumo Robot with Pololu Plug-in Modules, assembled

December 2013: Zumo Tournament Videos

Nick Moxley's DIY racing simulator

Posted by Brandon on 14 May 2014

Nick Moxley made a DIY seat mover (with two degrees of freedom) and shared his build on our forum. This racing simulator is powered by two of our Jrk 12v12 USB Motor Controllers with Feedback and controlled from the popular XSimulator software. The picture below shows Nick’s jrk motor controllers, which he modified by adding heat sinks for additional cooling.

This is one impressive build that I highly recommend checking out, especially if you are interested in making your own DIY racing simulator. You can find details about the parts he used (including where he found some of them) as well as many pictures documenting different parts of his build in Nick’s post on the Inside Sim Racing forum. A shorter version of this can be found in Nick’s post on our forum.

Tutorial: How to program a Zumo robot with Simulink

Posted by Kevin on 14 May 2014
Tutorial: How to program a Zumo robot with Simulink

We posted about a Simulink library for the Zumo robot recently, and now a tutorial that teaches you how to use that library to program a Zumo robot with Simulink is available on the Adafruit Learning System. The guide walks you through setting up a Simulink model to make the Zumo follow a specific trajectory, then loading the generated code onto the Zumo to see it run.

Related post: Zumo robots programmed with Simulink by MathWorks

Zumo robots programmed with Simulink by MathWorks

Posted by Kevin on 8 May 2014

MathWorks, the producer of technical computing software including MATLAB and Simulink, has released a Simulink library for the Zumo robot. The library provides blocks that represent all of the sensors and peripherals on our Zumo robot for Arduino, making it possible to program an Arduino-controlled Zumo robot using Simulink.

These Simulink-programmed Zumo robots have made a few appearances on MathWorks’ MakerZone blog. This article discusses the math behind programming a robot to follow a line, modeling the control system as a harmonic oscillator.

MathWorks also used several Zumos as part of a demonstration at the Robot Zoo, part of the 2014 Cambridge Science Festival. You can read more about their Zumo demonstration, as well as their other robot exhibits, in their recap of the event.

Related post: How to program a Zumo robot with Simulink

MiniTrack three-sided tracked robot

Posted by Grant on 24 April 2014

Let’s Make Robots user rhughes posted about MiniTrack, his custom-built tracked robot that features the ability to drive on each of its three sides. It uses our 30T track set and an extra pair of our 42×19mm sprockets. The tracks are driven by a pair of medium power 150:1 micro metal gearmotors, which are controlled by a DRV8833 dual motor driver carrier. MiniTrack also uses two Sharp GP2Y0D805Z0F digital distance sensors for object avoidance:

You can find pictures of various stages of the assembly of this robot and learn what else was involved in making it inside rhughes’s post.

PID line follower with 5" robot chassis

Posted by Claire on 18 April 2014

This PID line follower, originally featured in this Let’s Make Robots post by user Enigmerald, uses our 5" Robot Chassis along with 30:1 MP micro metal gearmotors, extended brackets, and our 42×19 mm wheels. Our QTR-8RC Reflectance Sensor Array is used to sense the line and our TB6612FNG carrier, along with an Arduino-compatible controller, is used to control the motors. A diagram of how everything is connected and the code for the robot are available in Enigmerald’s post. The post also has a link to a basic tutorial on PID tuning using the QTR array.

L3-G0: the full-size, LEGO R2-D2

Posted by Brandon on 14 April 2014
L3-G0: the full-size, LEGO R2-D2

Shawn and Lara Steele, known on the Pololu forum as kresty, built a functional, full-size, LEGO R2-D2 named L3-G0. L3-G0’s design is based on plans from the R2-D2 Builder’s Club, and it is made from around 16,000 LEGO bricks. It weighs roughly 30 kg (65 lbs) and can travel at a speed of 8 km/h (5 mph). The astromech has a fully functional rotating dome with multiple blinking lights. The dome is rotated using our 80mm wheel fitted with a high-traction sticky tire and powered by one of our 37D gearmotors. L3-G0 is controlled using a 9-channel RC transmitter and features an Arduino along with dedicated motor controllers and sound boards. Electric scooter motors were used for the drive wheels. The astromech also uses Pololu motor controllers and voltage regulators, as well as a SparkFun MP3 Trigger for audio. Continued…

Power Level Indicator for Ghostbusters Proton Gun

Posted by Arthur on 19 March 2014

Justin Chase Black (Throwing Chicken) is an artist and long-time laser cutting client who uses laser-cut parts in his prop and replica builds. Every time we ship a laser order to him, I eagerly await a new Facebook post showing off his latest project.

His work is extremely meticulous, skipping no detail in even the tiniest components. One of his more recent projects involves a tiny power level indicator on a “Proton Gun” replica from the movie Ghostbusters. Buying a power level indicator wasn’t an option; the ones he could find were made for aviation and cost over $1,000!

With a little trial and error, he was able to make them himself for a fraction of the cost by casting them out of resin, using our laser-cut parts to create the cast. A few of the design attempts did not come out well when cut from 1/8" acrylic since some of the features in the designs were much smaller than the thickness of the material (the design is only around 1/4" wide!). We cut various materials and thicknesses from 0.004" Mylar to 1/8" acrylic and a combination of thinner parts did the trick.

I’ll be sharing more awesome projects from Throwing Chicken in the future, but you can also check out his Artist page on Facebook for more updates. If you’d like to purchase a Ghostbusters Proton Gun Replica Kit, they’re sold on the Throwing Chicken Etsy shop.

If you have a cool project you’re working on and need some laser-cut parts: “Who ya gonna call?” (PO-LOLU!)

Power level indicator replica for Ghostbusters Proton Gun.

Vector plans for laser-cut power level indicator replica layers for molding.
Close-up of cast power level indicator replica case.
Close-up of cast power level indicator replica case with laser-cut interior layers.
Close-up of finished power level indicator replica.
Power level indicator replica with LEDs powered on.
Close-up of power level indicator replica with LEDs powered on.
Power level indicator replica installed in the Proton Gun.
Power level indicator replica installed in the Proton Gun with LEDs on.

Maestro-controlled Pan, Tilt, and Zoom (PTZ) dome camera

Posted by Brandon on 18 March 2014

Pololu forum member Dev255 modified a PTZ dome camera system to be controlled by an old Xbox joystick using a 24-channel Maestro servo controller. The Maestro reads 5 potentiometers on the Xbox joystick, along with some buttons, and correlates the readings to a speed and direction value. This data is converted to the Pelco D protocol that is used by the camera and gets sent to the camera from the Maestro. The LEDs on the joystick are used to indicate the program status. He also uses the Maestro to control a 4×20 character LCD display shown in the video below.

For more information on this project, see Dev255’s original forum post.