Posts by Jon
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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.
On Monday, Colin McGinn launched a Kickstarter in order to create a 3D short film using Tru.D 3D, which is a volumetric display system that he designed and patented. The system quickly feeds 3D volumetric objects into a specific viewing area, and each 3D piece forms a frame of an animation to tell a story that can be viewed from any angle.
Included among the Kickstarter rewards is a mini Tru.D 3D machine, which uses our micro metal gearmotors and magnetic encoders to perform a short, two-second animation. The machine is small enough to hold in your hands, and backers have the option of choosing from one of three different animations.
You can find more information on Colin’s project, including the full digital version of the short film, on his Kickstarter.
For their senior design project in the spring semester of this year, a team of Mechanical Engineering students (the Tuggiteers!) from Purdue made a remotely-controlled plane-towing vehicle that uses one of our step-up/step-down regulators. The team shared with us this video of their final review, which demonstrates the vehicle approaching, connecting to, and towing a single-engine aircraft:
This next video captures their vehicle’s first test. An on-board camera allows you to get a 1st-person view of the latch actuating and gripping the aircraft wheel:
We are always excited to see our parts getting used in cool projects, and we were especially excited to see this because it looks way easier than doing it the usual way:
Ben, pushing a plane (before he started Crossfit).
I got your torque right here ;)
Now that we are carrying Advancer Technologies’ MyoWare Muscle Sensor, it is time to update our demonstration video! I’ve had two whole years to add some mass to my biceps (during which time I continuously worked on those bad boys for a grand total of four weeks), and now I can proudly present to you these sick gains.
The demonstration is basically a redo of the original muscle sensor demo with the new sensor, except for a few small differences (honestly, my biceps are not that much bigger). In this setup, a 6-channel Maestro reads the muscle sensor’s analog voltage output and commands the position of a Power HD servo. The Maestro’s +5 V (out) pin supplies power to the MyoWare Muscle Sensor, and the servo and Maestro are powered by 4 rechargeable AA batteries. On a personal note, I found it really satisfying to use a single power source for this demonstration, which is not something you can do with the previous version of this muscle sensor, as it requires two supplies. (Be sure to check out the MyoWare Muscle Sensor’s product page to read about more ways the new muscle sensor improves upon the older version!)
This Maestro script is slightly more interesting than the script in the last demo, since the servo’s default direction of rotation was the opposite of the motion for a bicep curl (and we were already quite happy with the servo’s orientation with respect to my arm for the planned video footage). To get around this, and make the servo arm movement match the position of my arm during a bicep curl, I did some basic math and came up with an equation that you can see in the code below:
# Sets servo 1 to a position based on the analog input of the MyoWare Muscle Sensor. begin 8000 # put this value on the stack (for why, see line 5) 0 get_position # get the value of the muscle sensor's signal connected to channel 0 4 times minus # y = -4x + 8000 , which is an equation we use to deal with the servo's # default direction of rotation and scale the Maestro's Target # value to roughly 4000-8000 (approximately 1-2 ms) # which is the range of servo pulses that corresponds # to the motion we want. 1 servo # set servo 1 accordingly repeat
You can, of course, use other devices to read the analog voltages from the MyoWare Muscle Sensor. If you have not already, you might try using one of our A-Stars!
If you have a project that uses the MyoWare Muscle Sensor, we would be pumped to hear about it!
We are pumped to announce that we are now carrying Advancer Technologies’ MyoWare Muscle Sensor!
This sensor features a number of improvements over the older Muscle Sensor v3 including single-supply operation (no need for a negative voltage supply) and built-in snap connectors for electrodes. Other new features include a raw EMG output, reverse power protection, a power switch, LED indicators, and two mounting holes.
For a fun example that shows how you could use the muscle sensor, take a look at this blog post, which uses one of our Maestros to monitor a bicep while it is flexing, and command a servo to imitate the motion with a tiny cardstock version of He-Man’s arm. (Note that the project uses the older Muscle Sensor v3, not this new product.) You can also head on over to Advancer Technologies’ website for more project ideas.
Chris Barlow posted this interesting write-up about how he is using the USB connection of a Mini Maestro servo controller to prototype motion control for his hexapod robot. He has been going over the build in detail on his blog, so check it out over there, and be sure to take a look at this short video below:
Zippy is an RC balancing robot created by Larry McGovern. It uses an Arduino Nano to read pulses from an RC receiver and accelerometer and gyroscope data from an MPU6050. After processing that information, the Nano commands two ST motor driver development boards, which each control a 30:1 37D mm gearmotor with encoder. The whole system is powered by a 3S LiPo (brand: Zippy, of course!). You can watch Zippy scoot around on pavement below:
In the video description, Larry mentions that he modeled Zippy after the Balanduino robot, but we would like to highlight one noticeable difference: he used his own pair of wheels, which are mated to the output shaft of his gearmotors with our 6mm scooter wheel adapters! I had a major role in designing these, so on a personal note, it is especially exciting to see someone get a good use out of them. (It also looks like our stamped aluminum L brackets are used to mount the motors.)