Pololu Blog (Page 36)
Welcome to the Pololu Blog, where we provide updates about what we and our customers are doing and thinking about. This blog used to be Pololu president Jan Malášek’s Engage Your Brain blog; you can view just those posts here.
The overhaul of our RC switch and RC multiplexer products continues with the new Pololu 4-Channel RC Servo Multiplexer. This compact four-channel multiplexer of hobby radio control pulses allows for easy switching between two independent RC signal sources. An auxiliary channel selects whether master or slave inputs show up on the four output channels. This makes it ideal for applications in which you have two possible control sources and want to be able to switch between them on the fly.
For more information about the new Pololu 4-Channel RC Servo Multiplexer, see the product page.
- Our RC Switch overhaul is complete
- New product: RC Switch with Medium Low-Side MOSFET
- New product: Pololu RC Switch with Relay
Halloween’s always a good time at Pololu. Here’s a shot of all the people here that dressed up for the holiday:
I (Emily) used some of our LED strips to make a Luxor Hotel costume. (For those of you that don’t know, Pololu is located in Las Vegas, NV, not too far from this building.) You can see a video of this costume in action here.
If you used any Pololu products in your Halloween costume or decorations, we’d love to hear about it! Please post about it on our forum and maybe we will feature it here on the blog. Have a Happy Halloween!
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.
Do you like our Zumo Robot?
Does royal blue look good on you?
Do you like T-shirts that have robots on them?
Does the phrase “Push.” motivate you?
If you said “yes” to any of these questions, you might just be interested in our 2013 Pololu T-Shirt!
Some of our favorite examples of when/where to wear this T-shirt:
- In the delivery room!
- During a mini-sumo competition!
- During an actual sumo competition!
- Inside your local hackerspace!
- At your local robotics club meetings!
You can find these and last year’s shirts in our shirts category.
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.
Get a FREE copy of Elektor magazine’s November issue with your order while supplies last. To get your free issue, enter the coupon code ELEKTOR1113 into your shopping cart. The magazine will add 6 ounces to the package weight when calculating your shipping options.
For other issues and more information, see our Free Elektor Magazine Offers page. All issues are now available for shipping worldwide!
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.