Monthly Archives: November 2020

Creating a continuum tentacle-like robot with Arduino

via Arduino Blog

Continuum robots — which look like a tentacle or perhaps an elephant’s trunk — use a series of linkage sections and internal tendons to move both horizontally and vertically. While they may seem quite exotic, in the video below element14 Presents’ DJ Harrigan breaks down how he built one with an Arduino Mega and a fairly simple list of parts.

The robotic mechanism hangs down from a support structure, with universal joints allowing each section to bend, but not twist, with respect to the next one. These 10 sections are pulled in different directions using two servos and Kevlar cord, with user interface provided by two potentiometers. A third pot actuates another motor attached to the tentacle, acting as a gripper for tools, or whatever else Harrigan needs at the time!

App note: Driving electronic paper displays (E-paper)

via Dangerous Prototypes

Silicon Labs’ app note on driving E-paper with their EFM32 micro. Link here (PDF)

Electronic Paper Displays (EPDs) are types of displays that are reflective and bistable. Reflective in this case means that they rely solely on ambient light and does not use a backlight. Bistable is the property of retaining an image even when no power is connected.
EPDs are commonly used in e-readers, industrial signage and electronic shelf labels. Their properties are ideal for applications which do not update the image frequently. Since the display draws no current when showing a static image, they allow for a very long battery lifetime.

App note: Designing with an inverted-F 2.4 GHz PCB antenna

via Dangerous Prototypes

PCB design guide for an inverted-F 2.4 GHz antenna from Silicon Labs. Link here (PDF)

One of the main reasons to use a PCB antenna is to reduce cost. Since the antennas are printed directly on the board, they are generally considered to be free. On boards with room to spare, this will be true. On boards that need to grow to account for the increased size of the printed antenna, you must include the added cost of the larger PCB when calculating cost savings.

Controlling a gas convection heater with a custom thermostat

via Arduino Blog

Redditor “Higgs8” had a gas convection heater that is (or was) controlled manually, but they wanted something a bit more. To accomplish this, they came up with a small Arduino-based thermostat.

This allows you to set the desired temperature using a potentiometer, and it senses the current temperature value via a DS18B20 thermometer unit. It then adjusts the formerly manual knob with a stepper motor and custom gear reduction in response, maintaining the desired comfort level.

Feedback is displayed on a small OLED screen, which charts the room’s temperature over a 24-hour period. It also shows if the heater was on, letting you see if it was working properly.

More details can be found on Higg8’s Imgur page here.

Arduino psychic ‘magically’ guesses random numbers

via Arduino Blog

Standard Arduino Nanos can be used for many purposes, but they do not feature wireless capabilities. Somehow, though, Hari Wiguna’s Arduino psychic system is apparently able to pass data between two of them. No external communication hardware is implemented, yet one Nano is able to recognize when a random number chosen on the other Nano setup is input via an attached keypad.

As noted by Wiguna, it’s easier shown than explained, and you can see this techno-magic trick in action in the first clip. How things work is revealed in the second video, but can you guess how it’s done?

Code is available in the project’s write-up, which may provide some insight, however the hardware schematics – that appear to be accurate – will likely leave you amazed!

Our Black Friday/Cyber Monday Sale is going on now!

via Pololu Blog

Our Black Friday / Cyber Monday sale is going strong, and we have been working hard to make and ship the products that people are getting great deals on. Most of the sale coupons can be used on backorders if we happen to run out of stock, but you should still get your orders in early since lead times on some popular products can get long.

Please note that our same-day shipping guarantee has been suspended since we started operating with a reduced staff in March due to the COVID-19 pandemic (see Jan’s latest post here), though we will do our best to get your order shipped as fast as we can. Additionally, we are closed Thursday, November 26 (tomorrow) for Thanksgiving. Happy Thanksgiving!