by simsalapim @ instructables.com:
Ever been looking for your keys, and wanted to call them, before you realize that they are hideously analog pieces of metal? Or wanted to let someone into your house when you’re not at home, without having to lend them your keys?
Lockitron was the solution that descended from hardware heaven – a device that fits over the lock on your door and that is controlled via an app. It raised $2.2M on Kickstarter but missed its original shipping deadline by 1.5 years, leaving its backers in a deadlock (pun!). Are you one of them? Stop glaring at your empty mailbox and channel all your frustration into making your own awesome smartphone connected lock – The Bean Lock.
Open source BLE door lock - [Link]
by BrittLiv @ instructables.com:
Heating things up is one of the most performed tasks in a lab. Quite a lot of times it is not enough to simply hold something at a certain temperature, but the rate at which something is heated and for how long is just as important. Especially when you try to develop catalysts for chemical processes, the temperature program and exact temperature control is crucial and you probably do not want to stay in the lab for 16 hours to manually adapt your temperature program. Unfortunately, programmable temperature controllers that can automate processes are really expensive. So I decided to build a highly customizable controller that is able to run temperature ramps and read multiple different temperature programs from a SD card. It also provides a logging function on the SD card that allows you to evaluate the resulting temperature profile after running a program.
Programmable Temperature Controller + Hot Plate - [Link]
A four-channel remote control built using the EnOcean Pi by Kerry Wong:
In my last couple of blog posts, I did a brief overview of the EnOcean Pi sensor kit from Newark and demonstrated how to compile and run the example code using a Raspberry Pi. In this blog post, I will show a real world example – a four-channel remote control built using the EnOcean Pi in conjunction with the EnOcean pushbutton module.
A four channel remote control using EnOcean Pi - [Link]
A simple temperature control system for 3D print or other constant temperature control purpose by Xiang:
I plan to build a home-made 3D printer controlled by my Raspberry Pi, which, unfortunately, does not have any analog data acquisition pin. Therefore I decide to build a stand-alone temperature control system.
The idea is very simple. I use a power resistor as the heater and a thermistor as the temperature sensor. The system contains an LM324 quad op-amps chip. One op-amp is used as a comparator to compare the thermistor resistance with a nominal resistance and output LOW or HIGH as the comparison result. The other three op-amps inside the LM324 are used to perform some linear transformation and output a voltage that is proportional to the thermistor temperature. This voltage is applied to a 0-30V voltmeter so one can read the temperature. A N-Channel MOSFET transistor is used to control on/off of the heater.
Simple temperature control system - [Link]
Clap switch/Sound-activated switch designed around op-amp, flip-flop and popular 555 IC. Switch avoids false triggering by using 2-clap sound. Clapping sound is received by a microphone, the microphone changes the sound wave to electrical wave which is further amplified by op-amp.
555 timer IC acts as mono-stable multi-vibrator then flip-flop changes the state of output relay on every two-clap sound. This can be used to turn ON/OFF lights and fans. Circuit activates upon two-clap sound and stays activated until another sound triggers the circuit.
Sound Activated Switch - [Link]
These are the RFID readers I used. http://www.parallax.com/product/32390
Arduino RFID Card Door Lock System - [Link]
Control physical devices using an Arduino based home automation controller that connects to your network and lets you switch things on and off using a web browser. This episode shows the construction sequence of a controller that combines an Arduino-compatible board, Power-over-Ethernet, and relay driver shields to create a self-contained controller that can serve up its own web interface so you can click buttons in your browser to turn devices on and off.
Building an Arduino home automation controller - [Link]
Diogoc shared his Hakko T12 soldering controller in the project log forum:
I finally finished my Hakko T12 soldering controller.
Thanks to sparkybg and arhi for all help and sugestions.
Some features of the controller:
– 3310 graphic display
– rotary encoder for easy and fast temperature selection
– sleep mode when the iron is in the stand
– turn off when a long time in sleep mode
– audible indications
– intuitive menu navegation
– percentage visualization of output power
– powered by a compact and lightweight 24V dc laptop power supply
– ambient temperature sensor for a better cold junction compensation
– lcd backlight control
– alarm for very high temperature, turning off immediately the heater
– indication of tip removed to allow hot swapping the tips
– bootloader for easy firmware upgrade via integrated usb port
– usb port and c# software to monitoring all parameters and help to adjust the pid parameters
The controller still need a little adjust in the PID parameters but for me it is almost perfect.
Hakko T12 soldering controller - [Link]
The Project works as electronic toggle switch. The circuit is based on CMOS CD4013 Flip Flop IC, The circuit has two stable states, ON and OFF. Once it is ON, it remains ON till you press the switch again. A short button press of a tactile switch SW1 latches the circuit ON and another toggles it back OFF. Relay switch contacts can handle high AC Voltage as well as High DC current, this makes the project suitable for application like ON/OFF Fan, Light, TV, Pump, DC Motor, any electronic project required electronic toggle operations and few other devices work on AC voltage up to 250V AC or DC current up to 5Amps.
Electronic Toggle Switch - [Link]
0xPIT @ github.com writes:
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
Reflow Oven Controller with graphics TFT - [Link]