YouTuber Oracid1 has developed a unique family of four-legged robots, dubbed “FiveBarQuads.”

The quadrupeds all feature ultrasonic sensing for navigation and a body made out of LEGO components — and as seen in the first video below, his latest (and largest) version is able to navigate quite nicely on its own. It’s even able to traverse a grate and maneuver around a potted plant, though chair legs are understandably a bit tricky.

The robots use an Arduino Uno for control along with a total of 16 micro servos in its shoulders (four each) in order to move the limbs. Two servos are employed to actuate each upper linkage for the legs, which are attached to bottom sections, and finally to the feet portion through a series of joints. This allows for an interesting locomotion capability that could be applicable in a variety of situations.

Non-profits can do great work, and in order to help others visualize the needs they serve and what they are doing, Jason Wolin came up with an amazing map for his organization.

The massive map stretches down 14 feet of a brick wall, with the continents cut out of MDF, and a pair of accompanying LCD TVs that show data about different areas.

Three computers are used for control, two of which are used to play videos on each screen. The third handles overhead map lighting controlled via the DMX protocol to illuminate the map in various configurations. Each of the PCs are coordinated using a trio of Arduino Nanos, allowing video and lighting effects to be displayed in perfect sync.

Richard of ARITH-MATIC had the idea to build a 4-bit computer based on 7400 series ICs (like the 74HC273, 74HC193, and 74HC125), but other responsibilities got in the way of this becoming a reality for quite some time. Finally, with the Retro Computer Festival at the Centre for Computing History in Cambridge, England held earlier this month, he went ahead and started the project in hopes of creating a working computer in under 30 days.

The resulting homebrew CPU is known as the ‘Cambridge-1,’ comprised mostly of 7400 series ICs, wiring, and an SRAM chip for storage carefully arranged on a set of breadboards. In addition to the other components, an Arduino Micro is also implemented. While not technically a retro device, the Arduino allowed him to “change the control logic on-the fly,” and gave him the flexibility to finish the project in his compressed time scale.

As the name implies, the OSEP STEM board is an embedded project board primarily aimed at education. You use jumper wires to connect components and a visual block coding language to make it go.

I have fond memories of kits from companies like Radio Shack that had dozens of parts on a board, with spring terminals to connect them with jumper wires. Advertised with clickbait titles like “200 in 1”, you’d get a book showing how to wire the parts to make a radio, or an alarm, or a light blinker, or whatever.

The STEM Kit 1 is sort of a modern arduino-powered version of these kits. The board hosts a stand-alone Arduino UNO clone (included with the kit) and also has a host of things you might want to hook to it. Things like the speakers and stepper motors have drivers on board so you can easily drive them from the arduino. You get a bunch of jumper wires to make the connections, too. Most things that need to be connected to something permanently (like ground) are prewired on the PCB. The other connections use a single pin. You can see this arrangement with the three rotary pots which have a single pin next to the label (“POT1”, etc.).

I’m a sucker for a sale, so when I saw a local store had OSEPP’s STEM board for about $30, I had to pick one up. The suggested price for these boards is $150, but most of the time I see them listed for about $100. At the deeply discounted price I couldn’t resist checking it out.

So does an embedded many-in-one project kit like this one live up to that legacy? I spent some time with the board. Bottom line, if you can find a deal on the price I think it’s worth it. At full price, perhaps not. Join me after the break as I walk through what the OSEPP has to offer.

What’s Onboard?

There are plenty of input and output devices:

• 7 Push Buttons
• Potentiometers (3 rotary and 1 slide)
• Passive Infrared Sensor (PIR)
• Light Sensor
• Sound Sensor
• LM35 Temperature Sensor
• 10 LEDs (various colors)
• Servo Motor
• Stepper Motor
• DC Motor
• LCD Display
• Buzzer
• Speaker
• RGB LED

In addition, the kit comes with an ultrasonic distance sensor in a little bracket that can connect to the stepper motor. That’s the only part that needs power and ground that isn’t already wired up.

Because the heart of the board is an Arduino UNO clone, you can do anything you like to program it. However, OSEPP touts their visual block diagram language that is basically Scratch. You can use it for free on most platforms and there is even a Web-based version although it can’t download code. It looks like Scratch or other block-oriented systems you’ve seen before.

I’m not usually fond of the visual block languages, but this one at least shows you the actual Arduino code it generates, so that isn’t bad. But you can still use any other method you like such as the standard IDE or PlatformIO.

You can see a video about the board, below.

The Good and the Bad

The board feels substantial and able to withstand a good bit of abuse. There’s a good range of components, and I like that the arduino is a real daughter board and not just built onto the PCB. Despite using the block language, I do like the tutorial booklet. It is very slick and has projects ranging from an IR doorbell to a mini piano. You can see a page below — very colorful and clear.

Of course, the suggested retail price of $150 is a bit offputting. You might think a breadboard with a handful of LEDs and other parts would be a much lower-cost option but just look around for arduino kits for beginners and you’ll find prices are all over the place. On the other hand, with a parts kit you would have to know how to wire up things like stepper motors or DC motors, so there is some value to having it already done for you. There’s also value in not having a bag of parts to misplace.

The jumper wires in the kit have pins on one side and sockets on the other. The pins go into the Arduino’s connector and the sockets go over pins on the components. These aren’t quite as reliable as a spring clip and not as versatile either.

In my mind the worst part of the kit design is that the pins are right next to each of the components. That’s good for understanding, but it makes a mess of wiring. For instance, there are ten LEDs, and connecting them all means stretching jumper wires to both edges of the board The jumpers aren’t very long either, so any complex project is going to have wires crisscrossing the sensors and LCD.

Granted, in this image I could have removed some of the wires from the bundles but that wouldn’t help that much, either. If you need to hook up more than a few of the available components you will have a mess. I would have put some sort of spring clip or even screw terminals and put them all on the top and bottom of the board with clear color-coded marking about where they connect. Then the wiring would all be out of the way. There are probably a few other ways they could have gone, and at this price, they could afford the few extra inches on the PCB.

There are a few other things that would have been nice touches to finish off this kit. I would have enjoyed a short chapter in the booklet about using the Arduino IDE directly so that people know it exists. And having even a small breadboard attached for your own exploration would make sense, but would then call for a different type of jumper wire.

Short Example Using the Distance Sensor

I wanted to do something with the board so I decided to play with the distance sensor and the servo. The distance sensor is a bit annoying both because you have to wire it all up and it has a tendency to fall off when you transport the board.

The demo (you can find it online) won’t win any originality prizes. The program moves the servo to scan from 0 to 180 degrees in 5 degree increments. It measures the distance of what’s in front of it. When it completes a scan, if it saw something close (you could adjust the sensitivity), it moves the sensor back to that position and waits 30 seconds. Otherwise, it keeps scanning.

Really, this is no different from any other Arduino program. That’s kind of the point. Despite the emphasis in the book on the point-and-click language, this is really just an Arduino.

In Summary

For the deep sale price I found, the board will work well for its intended audience of students or anyone starting out with Arduino or microcontrollers. Even a more advanced audience who just wants a way to hammer out a quick prototype might find it worth the $30 or $40 you can sometimes pay. But at full price, it is hard to imagine this makes sense because of the mess of wire routing and limited expansion options.

Do you need a small weight scale? You can of course buy one, or you could instead make your own 3D-printed device with a load cell and an Arduino, as shown in the below video by MN Maker.

In his setup, the load cell first sends readings to an HX711 breakout board, which converts this analog signal into a digital output that the Nano can easily interpret. The output is displayed on a 0.96” 128×64 OLED, with a button on the back to switch power on and off, and another to tare the scale to zero. 

Code for the project is available here, while print files can be found on Thingiverse.

What really happens when you open the refrigerator door? Sure, you know intuitively that cold air escapes, but just how much? And how fast does the food inside actually heat up? To find out, Ryan Bates came up with his own data logging setup using an Arduino Uno, a custom sensor shield, and a microSD card reader.

His device uses a photoresistor to tell when the door has been opened, as well as a DHT22 temperature/humidity sensor to log the air temperature and door status. Along with this, TMP36 sensors are placed around the fridge to get a more granular look at temperatures, including one attached to a pickle jar. 

The results seen in the video below are quite interesting, and more information on the build can be found here if you’d like to try something similar.

As a kid you may have played Operation, but certainly never anything like this nine-foot-tall version from SPOT Technology. This device is not only impressively large, but assists doctors in their surgical pursuits with a CNC gantry setup to pull out obstructions.

In the game, amateur surgeons control the system using a small arcade cabinet next to the patient (Sergio), moving a magnetic gripper with a joystick and buttons. A camera rides along and transmits images to the cabinet, hopefully leading to a clean extraction. If the gripper isn’t aligned correctly, a button on the plunger reports the doctors error, and Sergio’s nose lights up red to indicate a failed surgery. Two Arduino Megas are implemented, one on the CNC playfield itself, another in the cabinet.

The project will be on display at the Philadelphia Mini Maker Faire on October 6^th if you’d like to see it in person.

Spilled wine may be a hassle to clean up, but you might also observe that it makes interesting patterns. Marketing firm KPS3 had the same sort of thought process when they created “The Santa Maria Swirl Machine” to promote the Santa Maria Valley wine industry.

The machine takes the form of a tabletop display, where a vacuum gripper first picks up a piece of paper and transports it into a clear “swirl area.” A glass is then automatically filled with wine, spun up to speed, and flung at the paper in order to create art. 

Control hardware includes an Arduino Micro and a pair of Raspberry Pi boards, along with cameras are used to stream the process and take a picture of the resulting pattern. If this sounds interesting, you can sign up to make your own spill-art here. You can also read more about the project on TechRepublic:

Visitors to the website can watch the current splash art being made, or register to join the queue to use the service—once their turn arrives, they are given a full-screen view and options to control their creation. Specialized watercolor paper is picked up by a servo equipped with a suction cup attached to a venturi (itself attached to an air compressor), which proceeds to hand off to a custom gripper to hold the paper in place for the wine to be spilled. 

From there, the Arduino-controlled stepper motor turns the lead screw, moving the paper into the splash zone, and fills the glass to the user-selected level, and begins to swirl the glass at the user-selected speed. Once the proper speed is attained, an actuator tips the glass forward, spilling the wine onto the paper. All of this is streamed by two cameras, with the final result photographed by a third. This photo is then processed in Lambda to clean up the photograph, detecting corners, applying filters and branding for the Santa Maria Valley Chamber of Commerce.

You’ve seen barcode scanners register the price for your groceries, and likely in many other applications, but did you ever consider if one could be made into an instrument? Well we now know the answer, thanks to this MIDI guitar by James Bruton.

Bruton’s amazing device presents a matrix of barcodes arranged on the instrument’s four necks, allowing him to select the note to be played with a scanner gun.

The scanned code then triggers a note that’s piped to an output device via an Arduino Mega and MIDI shield. A joystick, spinner, and arcade buttons are also available for functions such as note cutoff, changing the octave, and pitch bends.

Phones are pretty great. Used as telephones, they can save us from bad situations and let us communicate while roaming freely, for the most part. Used as computers, they often become time-sucking black holes that can twist our sense of self and reality. Assuming they pick up when you call, phones are arguably a good thing for kids to have, especially since you can hardly find a payphone these days. But how do you teach kids to use them responsibly, so they can still become functioning adults and move out someday? [Jaychouu] believes the answer is inside of a specialized lockbox.

This slick-looking box has a solenoid lock inside that can be unlocked via a keypad, or remotely via the OBLOQ IoT module. [Jaychouu] added a few features that drive it out of Arduino lockbox territory. To prevent latchkey children from cheating the system and putting rocks (or nothing at all) in the box, there’s a digital weight sensor and an ultrasonic sensor that validate the credentials of the contents and compare them with known values.

Want a basic lockbox to keep your phone out of reach while you work? Here’s one with a countdown timer.