Of the hundreds of projects I’ve shared over the years, none has attracted more attention than my DIY ECG machine on the cheap posted almost 4 years ago. This weekend I re-visited the project and made something I’m excited to share! The original project was immensely popular, my first featured article on Hack-A-Day, and today “ECG” still represents the second most searched term by people who land on my site. My gmail account also has had 194 incoming emails from people asking details about the project. A lot of it was by frustrated students trying to recreate the project running into trouble because it was somewhat poorly documented. Clearly, it’s a project that a wide range of people are interested in, and I’m happy to revisit it bringing new knowledge and insight to the project. I will do my best to document it thoroughly so anyone can recreate it!
Reflow Oven Controller with graphics TFT
This Reflow Oven Controller relies on an Arduino Pro Micro, which is similar to the Leonardo and easily obtainable on eb*y for less than $10, plus my custom shield, which is actually more like a motherboard.As I believe it is not wise to have a mess of wiring and tiny breakout-boards for operating mains powered equipment, I’ve decided to design custom board with easily obtainable components.The hardware can be found in the folder hardware, including the Eagle schematics and PCB layout files. It should fit the freemium version of Eagle
Überclocker Advance is the newest generation of my 30lb Sportsman’s class design, Überclocker. It retains the classic clamping-lifting fork arrangement of Überlocker Remix and the original Überclocker, but has significant practical design upgrades which make it quicker and more reliable.
Solar BMS (Solar Battery Management System) is a solar charge controller designed to replace the Lead Acid solar charge controllers most people use today in Offgrid, RV, Boats and multiple other applications with 12V and 24V systems. Solar BMS can be used with 3 up to 8 Lithium cells (any type) or supercapacitors. The new SBMS100 will have multiple improvements over the first generation SBMS4080 see further for details.
Simplified circuit diagram for the SBMS100 with max configuration.
(Two PV arrays each with 6x 250W PV panels for a total of 3kW of PV panels).
Next generation robots, drones and motorized scooter/skateboard/e-bike projects need efficient and resilient BLDC controllers, so if you’re also looking for a solid open-source brushless motor speed controller (BLDC ESC) for your project or knowledge/inspiration to bootstrap your own, then you most definitely want to have a look at VESC.
It’s a full open-source breed where hardware, firmware and support-software are available on github and no Windows or other crappy, proprietary systems are required for development or tuning/configuration.
If you need to discover the codes received from an unknown IR Remote type, use this Sketch from the IR Remote Control Library Examples first. (You must first install that library – the link is above).
(Copy and paste into a blank Arduino IDE Window), Upload to your Arduino and start the Serial Monitor window:
Tuning the Sonic Levitation Machine
This can be the hard and frustrating part when you first set up your Sonic Levitation Machine. Once you get it to work a few times, I promise you that setup is easy.
For best results, you can add an AMP meter to the circuit. There is a spot on the board and just be sure to cut the traces and put the current meter in series with the power source. Tuning is easy with a current meter. Just turn the trimpot so that the output is around 3 AMPs. No more than 3 1/2 amps is needed or you could overheat the driver board.
Plug the transducer cable and power supply into the board.
Adjustable 1-30V Laboratory Power Supply Uses Switching and Digital Control Technology, Arduio and 16X2 LCD
Denis @ envox.hr has designed a great PSU that is reliable, modular, programmable and of course Open source. The power supply is controlled by an Arduino and a touchscreen TFT screen is used to monitor and control it. It comes with a bunch of features you can check on the link below.
Through an H bridge a microcontroller can switch an electric motor in either direction. By software, the motor can be turned on until the sensor disc has been rotating for one step. In doing so a conventional brushed DC motor can be converted into a stepper motor. Number and direction of steps is commanded through the USB interface from a computer. If 16 steps are transmitted with a single command, the motor does a full turn without a break (assuming a sensor disc having four teeth).
The set point is permanently compared to the actual position of the sensor disc by the microcontroller and whenever there is a variation, the motor is controlled in such a way that the error gets minimized.
The Arduino can process up to 1600 pulses per second. At a revolution speed of 6000rpm (=100 revolutions per second), a sensor disc with four teeth can be scanned by the control loop.
DISCLAIMER: This design is experimental, so if you decide to build one yourself then you are on your own, I can’t be held responsible for any problems/issues/damage/injury that may occur if you decide to follow this build and make one yourself.
My workshop has a couple of bench power supply’s, one is an old Farnell TOPS 3D 3-rail tracking job, and the other is a 3-rail CSI CSI3005XIII with Constant Current functions. The farnell is all analogue but has no constant current control (current limiting only). The CSI is good but out the box doesn’t allow you to preset the constant current setting and thats what I want.
So, rather than buy another PSU I thought i’d design and build my own, something thats directly suited to me, my workshop & projects……..heck!, it’s a good excuse to have a damn good time!
This isn’t a full design blog but I’ve tried to document/add stuff as I go along, the idea being I’ll put all design documentation (schematic, partslist, Eagle PCB files, wiring diagrams etc) when it’s all finished.
Finally, please note that for the most part I have ignored the cost of this project. Some of the parts I’m using are indeed expensive, however, it’s based on parts I have lying around in the workshop as well a bit of expendature. The enclosure and some other items I have had to buy so when the final BOM is detailed I’ll make reference to supplier details.
Inspiration for my design comes from EEVblog.com & gerrysweeney.com.
Please note that the technical specifications are constantly changing thus are NOT final. I am constantly updating this article.
The miniE v2 is based on the Arduino DUE. This is because the computing power and the memory the DUE has to offer is needed to do the sort of things the miniEngine v2 is designed for. The mineEngine v2 can control two motors at the same time and thus two stepper-motor are required to do so.
Here is a list of major components needed to set up a miniEngine v2:
1x ITDB02-2.4E Display (320×240 Pixel, SD-Card, Touch) from ITEAD Studio – this is also available from other distributors – check your Search engine
1x miniEngine 2 Arduino shield (can be bought on www.airiclenz.com)
1x or 2x Stepper Motor Drivers (BigEasyDriver is recommended and supported)
1x or 2x Stepper Motors (up to 2A per phase)
1x 7V-15V Power supply capable of supplying up to 4A
This is how it looks like when fully assembled and connected to two motors and a DSLR (without an enclosure):
Here is a view from the bottom side that shows how the BED-board (which was designed to be a nice place for two Big EasyDrivers) is connected to the bottom side of the Arduino and also how it is connected (electrically) to the main shield:
This is the whole system including the main shield and all the components needed to make the magic happen:
Our code has become more and more functional, but we’re not quite there yet. In this part, I’m really going to bring the heat and tie all sorts of functionality into our code so that we have a fully operational time lapse control system – we’ll look at setting keyframes and adding a display to our setup.
The Input Stage or Preamp: Amplifies the guitar input signal and sends it to the Arduino microcontroller to be processed.
Arduino Board: It does all the Digital Signal Processing (DSP) modifying the signal and adding the effect (delay, echo, distortion, volume…).
The Output Stage: Once the waveform is processed, the signal is taken from the Arduino DACs and prepared to be sent to the Guitar Amplifier.
This part also includes a Summing Amplifier which is very useful for delay effects like echo or chorus.
Hi Fi Audio Amplifier Using LME49830
Project 41 showcases Texas Instruments’ LME49830 fully complementary, bipolar, ultra-high fidelity power amplifier input stage driver chip optimized for driving just about any available power MOSFETs. The LME49830 is a high performance driver that features low-noise, very low distortion, thermal shutdown and user adjustable compensation to minimize high-frequency distortion and an optimized slew rate. According to TI, the LME49830 IC can provide possible power output levels in excess of 1kW, if combined with a properly designed high current output stage topology and an adequate thermal management scheme.
The pilot prototype model has two paralleled MOSFET devices per side in the output stage. There is no power output protection included with this project. However, with the recommended power supply rails and voltage ratings of the power output transistors and the LME49830, there is enough margin of safety. The input sensitivity of the project is about 1.68Vpp resulting in a power output of more than 150 watts with an 8Ω load and ±60VDC to ±72VDC power supply rails with only convection cooling.
Following the success of our partnership with GreatScott! and the launch of the GreatScott! LED Color Organ Kit, we’re happy to introduce the new PCB version of this kit. With some careful thought and consideration, we’ve come up with a version that is more practical, easier to build, visually appealing, and flexible in how you choose to use it.
Digital Control for Laboratory Power Supply Using Arduino
The windows application I developed for this project allows full control over the controller with the added benefit of being able to graph/save data, upload new firmware (PicBasic Pro required), create/modify reflow profiles and export data to a *.csv file for import into Excel. This application was developed with C# 2010.
Here are some screen captures of the application:
Dual Level Lead Acid Battery Charger Based On BQ24450 & UC3606
I’ve just sent off for three PCBs from OSH Park for a lead acid battery charger. This is a classic “wheel reinvention” exercise, but I used it as an opportunity to do a deep dive into how the charger chip works as well as many other aspects of lead acid battery charging. It’s not perfect (the trickle current detection could best be described as “funky”), but this will do wonders for the Durham Makerspace sign batteries this fall. The images below are what OSH Park expects the boards to look like. A first cut at a layout for the top of the enclosure and what the enclosure looked like after my first ever laser cutter experience is below the boards. The schematic and Eagle and mechanical files will be on GitHub shortly.
Before I begin, you should have a general idea of how an SSTC works. I hope that my SSTC 2 page serves as a reasonably comprehensive introduction. Check it out if you are not familiar with SSTCs.
I haven’t heard of the term RSSTC used before, but I wanted to distinguish this coil from a regular SSTC due to the specificity of how this SSTC is run. Just as how a continually running SSTC is often referred to as a CWSSTC and the similar variant in the DRSSTC is known as the QCW-DRSSTC, I came up with RSSTC to describe its main characteristic features:
1. Instead of a rectified DC (smoothed or otherwise) to the inverter, the RSSTC takes in a ramped DC input
2. Resonant frequency higher than 300+kHz
3. The coil runs in sync with the ramped DC input
So what’s so different about an RSSTC compared to a conventional SSTC? – It is designed to produce straight, sword-like sparks, versus the characteristically bushy and branched sparks of conventional coils. In a way, it mimics closely the output behaviour of many Vacuum Tube Tesla Coils (VTTCs).
Till date, there has been very little academic research on the physics of spark formation, especially for those produced in Tesla Coils. Tesla Coils generally produce very branched ‘tree-like’ sparks, often resembling real lighting, taking the shape of plant roots. As amateurs began building more and more coils, they started to modify various coil running parameters to improve performance.
Creating sword-like sparks can be traced back to the early days of VTTCs, and was born out of result of trying to reduce the input power of a VTTC while maintaining a spark output length. Back in 1993, John Freau came up with the idea of achieving this in VTTCs by what he called a staccato operation – in his own words, “(running) the VTTC for a full AC half cycle, then (disabling) the VTTC for a selectable number of AC half cycles.” This has since become a staple design in VTTCs and helps significantly in preventing tube overheating. Today, the design is easily implemented as a simple zero voltage detector, triggering two 555 timers, one dictating the pulse duration and the other, the repetition frequency, among other designs.
Arduino: Control a DC or stepper motor from a potentiometer
One of the questions we commonly get asked is how to go about using an Arduino to control a motor from a potentiometer. Lots of people out there would like to do this but just don’t quite have enough programming knowledge to get an Arduino to do this. So to compliment the release of our new Arduino motor controller library (HCMotor) we’ve put together this quick tutorial to show you how to take advantage of this library to do just that.
To interface to the motor a stepper motor driver board such as the A4988 or in the case of this example the TB6560. You should choose a board that is capable of meeting the power requirements of your motor.
The MAX7219 LED driver is a handy IC for when you want to drive multiple LED’s. Although your Arduino may have plenty of digital IO pins for most applications, when you interface to LEDs such as seven segment displays or LED matrix modules you’ll very quickly run out of pins. The MAX7219 can take care of this and will allow you to control up to an array of 64 LED’s using just three digital pins. What’s more, these IC’s can by daisy-chained together to drive as many LED’s as you require, whilst still only using three IO pins.
PMDC WORM GEAR MOTOR
Name: PM DC Worm Gear Motor
Application: Application: fit for apparatus the shaft from gearbox is 90 degree to the motor.
Motor speed can be adjusted according to customers’ need.
Motor can match encoder, brake, P- thermal protector, D electromagnet brake.