Posts by Jon
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A while ago, I made a wedding gift for some friends, both of whom are avid Star Wars fans. The gift was basically a multi-piece decorative set that consisted of a modified toy Han Solo blaster, a stand to hold the blaster, and three edge-lit LED displays: one each of Boba Fett, Darth Vader, and Jar Jar Binks. I painted over the toy blaster to make it look more like it came straight out of the movies and added electronics so that it could interact with the displays (and the couple’s TV!).
The blaster uses IR TV remote codes to do several things: it can shoot the LED displays (and they’ll respond by blinking and playing audio recordings unique to each character), change the color and brightness of each display, and it can act as a limited TV remote by turning on or off the TV. At the heart of the blaster lies an A-Star 32U4 Mini ULV, which monitors the state of a switch, a couple of buttons, and a few potentiometers in order to decide which actions to carry out. The ULV version of the A* Mini is especially convenient for this setup because the toy blaster was originally powered by two AAA batteries, which produce too low of a voltage for a 5V microcontroller. The ULV’s built-in switching step-up voltage regulator allows it to operate directly off of the batteries and power the other components, unlike typical Arduinos that need at least 7V.
The blaster has two modes: one for shooting the displays and turning on/off the TV and another for adjusting color and brightness of the displays. Which mode the blaster is in is determined by the state of the programming mode switch, which is accessible with a flick of the thumb. While powered on, the A* continually checks to see if the programming mode switch is enabled. If it is disabled, the blaster will respond to trigger presses. When the trigger is depressed, the A* does two things: it sends a pulse train to a 5mm IR LED and drives an input pin low on an Adafruit Audio FX Mini sound board, which then outputs sound to a speaker through a 2.5W audio amplifier, producing DL-44 blaster firing noises. The blaster and displays use the IRremote Arduino library for sending and receiving the pulses. For these blaster shots, the blaster emits the IR TV remote code that corresponds to the generic power-on/power-off code for an LG TV. This same code is decoded by the Star Wars displays as a “hit” and the characters react to being shot. You can watch videos of those reactions in the YouTube playlist below (the playlist also includes the displays’ bonus Easter egg content, which is only accessible by sending certain button presses from the LG TV remote!). The sound level is a little low, so you might need to increase your volume to hear what the characters are saying:
If the programming mode switch is enabled, the blaster repeatedly emits a set of IR TV remote codes that contain information on what color and how bright the displays should be. Color is adjusted in the HSV color space using the blaster’s three rotary potentiometers (one each for hue, saturation, and value). There is also a linear potentiometer that can be used to set overall brightness (this effect combines with the change in brightness from adjusting the value potentiometer). So long as a display’s IR receiver can detect the IR signal sent by the blaster, the LED information can be decoded and the LED arrays can be updated.
Each display features a ~12″ tall profile of the head or upper body of a Star Wars character. The profiles are laser-etched onto a 1/2″ thick clear acrylic piece, which also has holes at its base. The holes allow the piece to be fastened to a recessed channel at the top of the display box. A short segment of an APA102C LED strip lines the bottom of the recessed channel and faces upward into the acrylic profile, which allows its light to disperse across the laser-etched surfaces. The display box has the same sound board and amplifier as the blaster, but uses a more powerful 1W speaker. An A-Star 32U4 Prime controls everything and power is supplied via a 9V 3A wall power adapter.
Compared to the rest of the system, the design of the blaster stand is pretty straightforward: it is just several pieces of 1/4″ plywood arranged into a frame that houses two channels. Those two channels have mounting holes which allow two clear acrylic pieces, which conform to the shape of the blaster, to be fixed to the frame. A lip along the inside of the frame makes it easy to mount the silver mirrored acrylic piece. The bottom of the mount features a personal well-wish from me to the couple. The message is written on the inside of the Alliance Starbird, which is cut from gold mirrored acrylic. The stand also houses some scrap metal parts (a bunch of prototype Zumo blades) to give it some weight. Four adhesive rubber feet, one for each corner of the stand, help make sure the stand doesn’t slide around easily and scrape the gold Starbird piece.
I owe a part of the inspiration of this gift to my coworker, Kevin, since in some ways I was basically trying to one-up his Harry Potter-themed wedding gift, which was given to another coworker, Brandon, for his wedding. Kevin also ended up helping me make some good decisions and generate some clean-looking CorelDraw files for the display cutouts/rastering. So, thanks, Kevin! You the real MVP.
Our favorite team of robot-making sisters over at Beatty Robotics has finished making another stellar robot! Their latest creation is a 1/10th scale functional replica of Curiosity, the rover from NASA’s Mars Science Laboratory mission. The rover uses a variety of Pololu products, both mechanical and electrical. For example, it uses a pair of G2 high power motor drivers to control six 25D mm gearmotors, each of which is coupled to a wheel with a 4mm hex adapter. The robot also features our voltage regulators, current sensors, logic level shifters, and pushbutton power switches. In addition to using our products, the rover also uses some stainless steel parts cut with our custom laser cutting service.
The Beattys are currently in the process of documenting their rover. Right now there’s a blog post out focused on the robot’s exterior, but the duo plans to also post about the electronics and functionality soon. We are looking forward to seeing more pictures and learning about how each part contributes to the whole system!
If you are curious to know more about the electronics inside of this replica rover, you can keep an eye on the Beatty website, or you can stay tuned to our blog – we will update you when they share more.
Erik Pettersson’s interactive sculpture, Roball, is a gripping take on the classic rolling marble kinetic sculpture. Roball uses a robotic arm to pick up a small ball and randomly place it on one of five tracks, where it twists and turns as it rolls down the track, eventually coming to rest at a holding station. The input to the system is a single pushbutton, and when the user presses the button, the arm picks the ball up wherever it stopped. Then, the device randomly selects another path, moves the marble to the start of that track, and releases it. A 12-channel Maestro controls the whole system and analog sensors (which might be our QTR-1A) at each holding station at the end of each track help not only detect the ball, but help the Maestro randomize its next move. Because of the ball’s non-uniform surface, the analog sensor will read different values depending on how the ball is positioned. That reading is then used in a calculation to determine what track to roll the ball on next.
You can learn more about this project on its Thingiverse page.
MIRR, which stands for Mobile Interactive Responsive Reflector, is an interactive installation that responds to people’s movement by independently rotating elements in its array of 98 mirrored panels. A FEETECH Mini Servo FT1117M actuates each panel and a total of five Mini Maestros control the servos. People can also use a custom box of arcade buttons to independently move each panel. You can read more about how MIRR works in this post on our forum.
A Maestro commands this Luftwaffe pilot to direct his steely-eyed gaze out into the wild blue yonder.
Klaus Herold, who makes RC models of World War II aircraft, used one of our Maestro servo controllers to elevate one of his German Luftwaffe models to new heights. A 6-channel Micro Maestro adds a touch of reality to his model by animating the movement of the head of the pilot. The movement has two degrees of freedom: the head rotates side to side and tilts up and down. Additionally, the cockpit canopy extends and retracts. You can see the pilot in action in the video below:
Our new Balboa T-shirts are here! They feature our latest robot, the Balboa 32U4 balancing robot, within an enlarged outline of the 43-tooth gear option for the Balboa gearbox, accompanied by our call to “Engage Your Brain”. These pre-shrunk cotton shirts are available in several colors (navy blue, cardinal red, or black) and a range of youth and adult sizes.
Here at Pololu, we think our Zumo 32U4 Robot is great! It’s one of our flagship products – a compact little robot packed full of features and tailored for mini-sumo. Whether you are a high school or college student learning to program through the Arduino IDE, or you are a C++ programming god and want to dabble in hardware for mortals, we think it’s a fantastic robot that you’d really enjoy. But, hey, you don’t have to take our word for it! Josh over at Breakout Bros has started a review series on robot kits, and recently posted his review of the Zumo 32U4. Check it out!
Have an opinion about that review? Maybe you have existing reviews of our products that you haven’t already shared with us? Feel free to post a comment about any of that below, or share your opinion on our forum. If you prefer, you can also contact us directly.
If you are looking for some inspiration for scary Halloween prop ideas, check out the truly creepy reaper puppet master that forum user rasco66 built! The prop is a tall, menacing installation: a grim reaper with glowing red eyes and outstretched hands overlooks a dark stage containing a lone skeleton. Once activated, the reaper commands the puppet to dance and animates its movement to a cover of Blue Oyster Cult’s Don’t Fear the Reaper. The skeleton animation is achieved with seven servos and a linear actuator; a Mini Maestro 24 controls all of the servo sequences and is triggered by a PicoBoo Max, which also coordinates the music, strobe, and linear actuator. You can watch a video of the prop on YouTube or read more about the project, including some code, in this forum post.
By the way, there are still 10 days left to take advantage of our Halloween sale and save on parts for your own grim reaper puppet master or whatever other terrifying thing you want to create (but you really shouldn’t wait that long if you want something done by Halloween as these things almost never work on the first try!).
Wildlife photographer Stéphane Simoëns uses a remote-controlled, camouflaged vehicle to bring his camera closer to animals without scaring them away. The vehicle is a custom-built, metal-framed, 4-wheeled chassis that is controlled with a pair of our TReX dual motor controllers. One TReX drives while the other provides tilt control for the onboard camera. The vehicle also features three of our RC switches; one switches on and off the video transmitter and the other two control camera shutter and focus. You can find more information about this project in Stéphane’s forum post.
Forum user LuisLabMO posted about his WiFi-controlled plant watering and monitoring system. The system uses SparkFun’s Blynk ESP8266 board to read various sensors that monitor sunlight, moisture content of the soil, and detect the level of water remaining in the watering reservoir. The Blynk signals our 5V relay module to activate the system’s water pump, which irrigates the plants through a drip system. You can read more about LuisLabMO’s watering system in his post, which also has a link to his Hackster.io project page and GitHub repository.