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While our laser cutting machines can only cut two dimensional parts, there are easy ways to make three-dimensional designs out of flat, laser-cut parts. A simple way to achieve this is to create slots in the vector design to allow the two parts to slide together perpendicular to one another. Some may remember this technique from childhood arts and crafts; this easy tweak allows parts to be easily assembled and disassembled.
These Chandeliers by Nicole Ketchum were created using our 3 mm acrylic with a slot width of 1/8″. You can adjust the width of the slot depending on how snug you’d like them to fit. Since Nicole’s chandeliers are meant to be hung out of reach, a really snug fit wasn’t needed. With the holidays right around the corner, these could spruce up any room of your home!
For more details on using slots to fit acrylic parts together, be sure to check out Nicole’s project in our Custom Laser Cutting Gallery. More details about our custom laser cutting service can be found here.
Pololu forum user Martan recently released a project called Wireless Servo Widget. The project website says:
Wireless Servo Widgets allow you to control up to 64 slaves, with each slave controlling up to six R/C type servos. In addition, each slave can return 3 analog input values to your Raspberry Pi. Slaves have a range of about 50 feet from the master. Use them for home automation, robotics, model train controls, or whatever you want!
The Wireless Servo Widget is based on our Wixel Programmable USB Wireless Module. Martan wrote apps for the Wixel that use the packet addressing feature of the CC2511F32 chip to implement a round-robin protocol. He also made a Slave Widget Breakout Board which makes it easy to plug servos into the slave Wixels. All of this and more can be found on the Wireless Servo Widget website.
Halloween is just around the corner, and people are looking to make fun costumes. I recently took a couple of calls from customers who were looking to make Katy Perry-inspired costume dresses with spinning peppermints, following the instructions found on this RPF forum thread. Parts from Pololu used to make the dress included an enclosed 3-AA battery holder with a switch and a Solarbotics GM3 224:1 Gear Motor. However, we suggest substituting our 200:1 Plastic Gearmotor, which has similar performance but no back shaft that needs to be removed.
If you have a cool costume that uses our products, please feel free to share them in the “Share your projects” section of our Forum.
Geoff from Tabletop Robotics wrote a tutorial on how to build a Flipbot, a basic differential-drive robot that can keep on going even when flipped upside-down. A Wixel serves as the brains of the robot, and a second Wixel in the remote allows the Flipbot to be wirelessly controlled. In addition to the Wixels, the Flipbot uses a number of Pololu products, including:
- Two micro metal gearmotors
- 22T track set
- DRV8833 dual motor driver carrier
- MMA7361L 3-axis accelerometer
The accelerometer is used to determine when the robot is upside-down. Geoff’s tutorial has a full parts list and a diagram of how everything is connected; the complete source code is also available.
Thomas Schoch, of Essen, Germany, built a neat robot with a Raspberry Pi and a Zumo Chassis Kit. The PiBot-B is controlled by a custom iPhone app that communicates over WiFi to the Raspberry Pi, which is running lighttpd and PHP. A Python program uses the WiringPi library to send signals to an L293D motor driver that drives the two 100:1 Micro Metal Gearmotors in the Zumo chassis. The iPhone app displays video from the attached Logitech C300 webcam, and the robot has an integrated 8×8 LED matrix from Adafruit that indicates its state. In the future, Thomas plans to add sensors for obstacle detection and make the robot autonomous. We were impressed by several things:
- PiBot-B is very tidy, thanks in part to the USB cables that were shortened and modified using liquid rubber.
- The Raspberry Pi has only one PWM output so Thomas used two OR gates to select whether the left motor, right motor, or both motors receive the PWM signal.
- The write-up has some great photos and informative diagrams.
The PiBot-B page is written in German, but it has a link at the top to translate it into English using Google Translate.
Lonnie Honeycutt made a nice tutorial on how to make a simple beginner robot that uses many parts that you can find on our website. The tutorial breaks down the construction of the robot into different parts and includes videos that help demonstrate how to build the robot. It also includes links to some of our products used in the robot, like the TB6612FNG Dual Motor Driver Carrier, Pololu Robot Chassis, and the Tamiya 70097 Twin-Motor Gearbox Kit. Check it out if you are looking for a project to get you started.
Here are links to three parts of the tutorial he has posted so far:
Part 1: Arduino robotics – motor control
Forum user Erich created a custom Zumo Robot Chassis PCB to use with our Zumo chassis kit. The board is designed to accept a large number of plug-in modules, such as a DRV8835 dual motor driver carrier, encoders, and voltage regulators. Sensors that can be mounted on the robot include a Zumo reflectance sensor array, some distance sensors, and an ultrasonic sensor, and it also supports several wireless communication modules. Instead of an Arduino, it uses a Freescale FRDM-KL25Z as the microcontroller board.
You can follow his robot’s progression 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.