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For the recent LVBots dead reckoning competition that was hosted here at Pololu, I decided to make a robot based on the Baby Orangutan robot controller. This post details my robot and some of the considerations made while I went through my design process. If you would like more details about the competition rules and how it was judged, see the LVBots dead reckoning rules (23k pdf).
I started by choosing my parts and making sure that my robot, which would later be named “Baby Blues”, would be able to function in the way I wanted. I decided on using the Baby Orangutan because of its integrated motor driver and compact size. Continued…
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!)
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.
Chris Eckert makes devices that explore the artistic potential of factory automation. One of his works, entitled ToDo, is an automated wall mounted device that seems to continuously write a never-ending list of things to do. Two stepper motors control the position of a pen over a roll a paper, and a servo controls the pen’s up/down movement. The device is controlled by an Arduino Uno and two of our A4988 stepper motor drivers. You can find more details about the construction in Chris’s blog posts about Todo and see more of Todo on its gallery page.
Chris is currently working on another project called Babel, which will feature about 20 devices similar to ToDo.
You can learn more about Chris and his artwork on his personal website.
Several people here at Pololu made robots to compete in the LVBots dead reckoning competition last week. This post is about the robot I made along with another engineer here.
Dead reckoning is the process of continuously calculating your position using internal sensors that tell you something about what speed and direction you are going. In our dead reckoning competitions, robots demonstrate that they are capable of dead reckoning by following a long, twisting line drawn on the floor and then driving back to their starting point. The line functions as a user interface that directs the robots through a sequence of moves for which it was not preprogrammed. The robots are scored based on the time they took and how close they were to the starting point at the end. Continued…
Forum user solderspot recently posted on our forum about some modifications he’s been making to his Zumo robot. First, he added our optical encoders for micro metal gearmotors to his robot, which required using motors with extended back shafts and cutting holes in the chassis to route the wires from the encoders.
This allows his Zumo to navigate by dead reckoning, using just the information from the encoders.
He also mounted a sonar sensor on a servo to his robot, which enables it to find its way around a room by following the walls.
A series of articles on solderspot’s blog, starting with this one, covers his experience building and programming his robot. It looks like solderspot has further plans for the Zumo, including more sophisticated autonomous navigation, so watch his blog if you want to keep up with the latest developments.
Local indie artist and Pololu employee Tracey, intent on reviving her programming skills and exploring her budding interest in electronics, shed some light on her creative personality by making an LED banner for her band, Hope’s Edge. The banner is a briefcase-sized container that uses an addressable LED strip to shine through a stencil of the band’s logo in a wave of brilliantly changing colors. The stencil and the rest of the panels in the container are made from 1/16" black ABS, all of which were cut with our custom laser cutting service, and a sheet of gift-wrap tissue paper is taped to the inside of the front panel to act as a diffuser. The banner runs off of a 5V wall wart, which is boosted to 9V to power an Arduino Uno that runs Ben’s Christmas light LED code.
Forum user Hardsuit posted in this thread about the hub adapters he 3D printed for his robot, which is a roughly 1/4 scale RC Tachikoma from the Ghost in the Shell: Stand Alone Complex anime series. The adapters allow some of our universal mounting hubs to be used with VEX 4″ Mecanum wheels. You can find and download his STL file on Thingiverse.
The Tachikoma, which he has named Sapporo, also uses our Simple Motor Controller 18v15 and 29:1 Metal Gearmotor 37Dx52L mm. Some of the engineers here are GITS fans, and we are definitely looking forward to seeing it completed!
Frédéric Jelmoni built a neat robot with a Raspberry Pi and a Zumo Chassis Kit. The Raspberry Zumo robot can be controlled over WiFi using telnet. The server on the Raspberry Pi is written in Python and uses the RPIO library to send signals to an SN754410 motor driver that drives the two 100:1 Micro Metal Gearmotors HP in the Zumo chassis. The server also controls an RGB LED and a buzzer. A stripped-down Logitech webcam attached to the front of the robot provides video that is streamed over the web using mjpg-streamer.
Erich, a professor at the Lucerne University of Applied Sciences and Arts in Switzerland, posted to our forum about their first Mini Sumo tournament, which took place this past weekend. The tournament was a part of Erich’s embedded systems programming class, for which he created a custom Mini Sumo robot platform for his students to modify. His robots use a custom PCB that mounts to the Zumo chassis kit and connects to the reflectance sensor array. Instead of an Arduino, his PCB uses a Freescale FRDM-KL25Z as the microcontroller board. Students customized the modified Zumos with their own sensors (we saw at least a few of them using our IR proximity sensors). 21 robots were entered into the competition, and a winner was determined over 5 rounds. Links to a competitor showcase video, several battle videos, and more information about the competition can be found in his forum post.
We are also excited to see a list of performance tweaks that Erich created for Zumo robots to be more competitive in Mini Sumo. We have made this available as a resource on the Zumo product pages.
While he was experimenting with our Zumo chassis, Erich posted to our forums a few times updating us on the progress of his modifications. 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
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