Flywire Circuits At The Next Level

The technique of assembling circuits without substrate goes by many names; you may know it as flywiring, deadbugging, point to point wiring, or freeform circuits. Sometimes this technique is used for practical purposes like fixing design errors post-production or escaping tiny BGA components (ok, that one might be more cool than practical). Perhaps our favorite use is to create art, and [Mohit Bhoite] is an absolute genius of the form. He’s so prolific that it’s difficult to point to a particular one of his projects as an exemplar, though he has a dusty blog we might recommend digging through [Mohit]’s Twitter feed and marveling at the intricate works of LEDs and precision-bent brass he produces with impressive regularity.

So where to begin? Very recently [Mohit] put together a small wheeled vehicle for persistence of vision drawing (see photo above). We’re pretty excited to see some more photos and videos he takes as this adorable little guy gets some use! Going a little farther back in time there’s this microcontroller-free LED scroller cube which does a great job showing off his usual level of fit and finish (detail here). If you prefer more LEDs there’s also this hexagonal display he whipped up. Or another little creature with seven segment displays for eyes. Got those? That covers (most) of his last month of work. You may be starting to get a sense of the quality and quantity on offer here.

We’ve covered other examples of similar flywired circuits before. Here’s one of [Mohit]’s from a few years ago. And another on an exquisite headphone amp encased in a block of resin. What about a high voltage Nixie clock that’s all exposed? And check out a video of the little persistence of vision ‘bot after the break.

Thanks [Robot] for reminding us that we hadn’t paid enough attention to [Mohit]’s wonderful work!

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DIY Telepresence Robot Built From Off-The-Shelf Parts

Petite, but it does the job. Note the huge LED headlight in the center.

Telepresence hasn’t taken off in a big way just yet; it may take some time for society to adjust to robotic simulacra standing in for humans in face-to-face communications. Regardless, it’s an area of continuous development, and [MakerMan] has weighed in with a tidy DIY build that does the job.

It’s a build that relies on an assemblage of off-the-shelf parts to quickly put together a telepresence robot. Real-time video and audio communications are easily handled by a Huawei smartphone running Skype, set up to automatically answer video calls at all times. The phone is placed onto the robotic chassis using a car cell phone holder, attached to the body with a suction cup. The drive is a typical two-motor skid steer system with rear caster, controlled by a microcontroller connected to the phone.

Operation is simple. The user runs a custom app on a remote phone, which handles video calling of the robot’s phone, and provides touchscreen controls for movement. While the robot is a swift mover, it’s really only sized for tabletop operation — unless you wish to talk to your contact’s feet. However, we can imagine there has to be some charm in driving a pint-sized ‘bot up and down the conference table when Sales and Marketing need to be whipped back into shape.

It’s a build that shows that not everything has to be a 12-month process of research and development and integration. Sometimes, you can hit all the right notes by cleverly lacing together a few of the right eBay modules. Getting remote video right can be hard, too – as we’ve seen before.

Smooth Moves From Cheap Motors

Building an electric motor isn’t hard or technically challenging, but these motors have very little in the way of control. A stepper motor is usually employed in applications that need precision, but adding this feature to a motor adds complexity and therefore cost. There is a small $3 stepper motor available, but the downside to this motor is that it’s not exactly the Cadillac of motors, nor was it intended to be. With some coaxing, though, [T-Kuhn] was able to get a lot out of this small, cheap motor.

To test out the motors, [T-Kuhn] built a small robotic arm. He began by programming his own pulse generating algorithm that mimics a sine wave in order to smooth out the movement of the motor. An Arduino isn’t fast enough to do these computations, though, so he upgraded to using the ESP32. He also was able to implement the inverse kinematics on his own. The result of all this work for a specific platform and motor type is a robotic arm that has a very low cost but delivers performance of much more expensive hardware.

The robot arm was built by [T-Kuhn] too, and all of the details on that build, as well as all the schematics and code, are available on the project site if you need a low-cost robot arm or a good stepper motor controller for a low cost. There are many other ways of getting the most out of other types of low-cost motors as well.

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An In-Depth Look At Dexter, The Robotic Arm

Dexter, a really great robot arm project, just won top honors in the 2018 Hackaday Prize, and walked away with $50,000 toward continuing their project. As a hat tip to Hackaday and the community, Haddington Dynamics, the company behind Dexter, agreed to open-source their newest version of Dexter as well. As James Newton said when accepting the trophy during the award ceremony, “because of your faith in us, because of this award, we have been moved to open-source the next generation of Dexter.” Some very clever work went into producing Dexter, and we can’t wait to see what further refinements have been made!

Dexter isn’t the only robotic arm in town, by any means. But in terms of hobbyist-level robotics, it’s by far the most complete robot arm that we’ve seen, and it includes a couple of design features that make both its positional accuracy and overall usability stand out above the rest. This is a robot arm with many of the bells and whistles of a hundred-thousand dollar robot, but on a couple-thousand dollar budget. Continue reading “An In-Depth Look At Dexter, The Robotic Arm”

Robot Never Misses Leg Day

We have heard bipedal walking referred to as a series of controlled falls, or one continuous fall where we repeatedly catch ourselves, and it is a long way to fall at 9.8m/s2. Some of us are more graceful than others, but most grade-schoolers have gained superior proficiency in comparison to our most advanced bipedal robots. Legs involve all kinds of tricky joints which bend and twist and don’t get us started on knees. Folks at the Keio University and the University of Tokyo steered toward a robot which does not ride on wheels, treads, walk or tumble. The Mochibot uses thirty-two telescopic legs to move, and each leg only moves in or out from the center.

Multi-leg locomotion like this has been done in a process called tensegrity, but in that form, the legs extend only far enough to make the robot tumble in the desired direction. Mochibot doesn’t wait for that controlled fall, it keeps as many downward-facing legs on the ground as possible and retracts them in front, as the rear legs push it forward. In this way, the robot is never falling, and the motion is controlled, but the processing power is higher since the legs are being meticulously controlled. Expecting motion control on so many legs also means that turns can be more precise and any direction can become the front. This also keeps the nucleus at the same level from the ground. We can’t help but think it would look pretty cool stuffed into a giant balloon.

Some people already know of tensegrity robots from NASA, but they may not know about the toolkit NASA published for it. Okay, seriously, how did knees pass the test of evolution? I guess they work for this jumping robot.

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Low-cost Autonomous Rover Will Drive Your Projects

[Miguel] wanted to get more hands-on experience with Python, so he created a small robotic platform as a testbed. But as such things sometimes go, it turns out the robot he created is a worthy enough project in its own right. With a low total cost and highly flexible design, it might be exactly what you’re looking for. Who knows, it might even bootstrap that rover project that’s been wandering around the back of your mind.

The robot makes use of an exceptionally simple 3D printed frame. No complicated suspension to worry about, no fasteners to hold together multiple printed parts. It’s just a single printed “L” shaped piece that has mounts for the motors and front sensor board. As designed it simply drags its tail around, which should work fine on smooth surfaces, but might need a bit of tweaking if you plan on taking your new robotic friend on an outdoor adventure.

There’s a big open area on the “tail” to mount a Raspberry Pi, but you could really put whatever board or microcontroller you wish here. In the nose is an HC-SR04 ultrasonic sensor, which [Miguel] is using to perform obstacle avoidance in his Python code. A dual H-Bridge motor driver controls the pair of gear motors in the front to provide propulsion and steering, and a buck converter steps down the 7.4V from the 2S LiPo battery to power the electronics. He’s even included a mini breadboard so you can add circuits or sensors as experimental payloads.

If you’re looking for a slightly more advanced 3D printed robotics platform, we’ve seen our fair share. From the nearly fully printed Watney to a tank that looks like it’s ready for front-line combat.

A Robotic Arm For Those Who Like Their Kinematics Both Ways

A robotic arm is an excellent idea if you’re looking to get started with electromechanical projects. There’s linkages to design, and motors to drive, but there’s also the matter of control. This is referred to as “kinematics”, and can be considered in both the forward and inverse sense. [aerdronix] built a robotic arm build that works in both ways.

The brains of the build is an Arduino Yun, which receives commands over the USB interface. Control is realised through the Blynk app, which allows IoT projects to easily build apps for smartphones that can be published to the usual platforms.

The arm’s position is controlled in two fashions. When configured to use inverse kinematics, the user commands an end effector position, and the arm figures out the necessary position of the linkages to make it happen. However, the arm can also be used in a forward kinematics mode, where the individual joint positions are commanded, which then determine the end effector’s final position.

Overall, it’s a well-documented build that lays out everything from the basic mechanical design to the software and source code required to control the system. It’s an excellent learning resource for the newcomer, and such an arm could readily be used in more complex projects.

We see plenty of robotic arms around these parts, like this fantastic build based on an IKEA lamp. If you’ve got one, be sure to hit up the tip line. Video after the break.

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