Arduino based Spot welder for 18650 batteries

spot welder

Lots of devices are using battery packs that are spot welded together. Spot welding ensures great connectivity and vibration safe operation. In order to spot weld, you need special equipment that can give high current output for the very short time duration. This way you can get good weld joints without damaging the batteries with heat. Building a spot welder for small tasks is fairly easy. KaeptnBalu has shared his instructable where he assembles his spot welder which is controlled by Arduino Nano. Spot welder requires 7-12V power source capable to output high currents. So any lead-acid battery works fine. Arduino is used to controlling welding pulse duration which can be adjusted from 1 to 20ms. With 0.15mm nickel strips he found that 9ms gives the best result. First of all, he prototyped the spot welder and then built his custom PCB where he put 8 MOSFETs in parallel that switch current on and off. He also built plywood foot pedal switch to keep his hands free while soldering. If you get lost among welding terms, check out an excellent… Continue reading

Arduino based MPPT solar charge controller

If you are going to harvest solar energy with photovoltaic elements you need a proper charge controller that would take power from panels and convert it to suitable voltage that can be further used for charging or simply powering devices of your choice. The main problems with charge controllers are associated with efficiency. We need that controller power losses were minimal as possible, another point is to take as much power from solar panels as possible. In order to take the most of panel, controller should keep track of maximum power point in element’s I-V curve. This is how modern converters work. This is already third version of solar controller built by deba168. It uses Arduino Nano which controls series of thing including reading voltage and current flowing from solar panel, driving buck converter so that maximum power could be drawn. Then senses voltage on a battery which is being charged. Optionally it controls load MOSFET which drives loads from battery. Arduino is equipped with LCD and WiFi adapter for user interactions. Using MPPT method solar harvesting efficiency can be… Continue reading

Arduino Nano Self-Balancing Robot

An engineering student must have heard about PID controllers, which are useful parameters in any control system design. A self-balancing system uses this PID Controller along with kalman filter. This project is not only useful to hobbyist or students but also teachers. It’s more of a PID teaching tool implemented on a self-balancing bot and demonstrates what are the effects of different PID parameters on the object. It changes its PID values In real time with the help of three different potentiometers attached on-board. Everything can be brought from spark-fun, however a part on the bot has been 3d-printed. It’s built around an Arduino Nano along with a 6 degree of freedom sparkfun IMU sensor with additional peripherals such as motor driver, lipo battery e.t.c . The PCB is custom designed, however the files are available. Although the code might be little tough to understand at first sight, but it works perfectly.It also has positioning return system which takes the amount of time the motors are tuning in each direction and the speed and figures out how far away it… Continue reading

Easy to build temperature monitor

The project is all about temperature monitoring and displaying with a twist. Instead of using a costly Arduino with a boot loader, the author used Arduino Nano as it’s cheap but it doesn’t have an on-board boot loader. He used a Bus Pirate V3B to flash the boot loader and save on some extra-bucks. In the initial phase, the author started with a DHT11 sensor which is a SPI based temperature and humidity sensor having digital output. However, since he wanted an accuracy in decimals, he shifted to DS18B20 which is again a SPI based temperature sensor from Maxim. It has an accuracy of +/- half degree Celsius. For displaying the graphs of temperature variations along the day, he used an old Nokia 5110 lcd which Is again very cheap to buy. He also decided to make small circular buffer for DS18B20 readings and draw that as scrolling graph, RRD style. At last step he also added PWM driven back-light to display which is off if value didn’t change, half-dimmed if current temperature is lower than previous one or full… Continue reading

Vertibot – lightweight two wheel balancer

Two wheel balancing robots are fun to watch. They are unusual to our eyes and always seems that it will fall. The secret is that those balances constantly struggle to fight the flipping by adjusting its vertical position. This is how famous Segways work – they constantly try to keep vertical. Simple enough, but when you try to build something similar, there are quite enough technical challenges. Madefrutos have built a lightweight balancing robot based on Arduino Nano, which packs some interesting features. The robot so called VertiBOT was built with educational intent. The control algorithm uses kalman and complementary filter methods along with PID. Each wheel is driven by two small motors that are controlled by Atmeta328 in Arduino Nano. Robot determines its current position using 6 DOF accelerometer and gyro ADXL345/ ITG3200. Robot chassis has been 3D printed that makes it really unique. Since it is more educational project, you will find a nice description along with some theory that might help you to build your own balancer. Continue reading

The Greatest Things You Must Know About Arduino Nano!

For most of the home hobbyists, one of the most common breadboards to you must be the Arduino type breadboard! The reason why the Arduino breadboards are so popular because of its high quality and cheaper cost than other boards. You can find Arduino Breadboard available in many types and the Arduino Nano is the smallest, complete and breadboard friendly of all. Arduino Nano is a fine surface mount breadboard embedded version with neat integrated USB on it. The Arduino Nano was been well designed and is being produced by Gravitech. Arduino Nano has everything what Diecimila has. Plus, it has more analog input pins and onboard +5V AREF jumper. Maybe you will find out that power jack and power select jumper was missing in Nano. Well, since the Nano can be automatically sensed and switch to the higher potential source of power, thus it’s no need to include the power select jumper on it! Another interesting feature about the Nano is it got the breadboard-ability of the Boarduino and the Mini+USB with smaller footprint, thus you will have more… Continue reading