Autonomous Goalie

This project will definitely be liked by people who loves playing air hockey. In short term, it’s a low cost robot which detects a puck coming towards it and moves in its required direction to stop it. The great point of the project is, it’s highly responsive and doesn’t use any robotic arms to stop the puck. The heart of the project, an ATMEGA 1284 MCU, takes in echo patterns from each of the sensors, interprets them and accordingly actuates the robots motors. Moreover, it requires negligible human input and can also be powered from a battery based source. Due to multiple tasks running simultaneously, they have used a tiny real time kernel to execute task in a coordinated manner which has made the robot more responsive to the puck. In the final design, with all the sensors mounted on the robot, a threshold of about 34cm or 1 foot was observed to do the best job of detecting the puck and resulting in proper functioning of the robot. A low cost robot doing a job of the goalie in… Continue reading

Universal Remote

We all have faced the problem of managing multiple remotes while using our home theater. Although there are commercially available universal remote, this project will allow you to make your own universal remote controller and hence will teach you the working of a remote. In short, it learn the required signal of different remotes all at once, store them and can transmit them based on the input received from the user on the remote. A typical NEC protocol is used to implement the remote control but with a little modification you could also use RC-5 protocol Presently, it only has the capacity to store 9 buttons due to the keypad being used, however, you could replace with a touch screen based LCD to store more signals and increase the attractiveness of the project. The microcontroller used for this project is Atmega1284 mounted on a custom PCB. When the device is in input mode, microcontroller is used to detect IR signal to store the signal of your remote. When the device is in output mode, microcontroller detects user input and generates… Continue reading

Automatic Liquid Mixer

This project is done by Justin and Austin who studies at Cornell University. This project doesn’t require any human interaction except placing the glass at the correct position to make a mixture of drinks. The user can select the required drink from up to 16 predefined drinks and then all he has to do is place the glass, the project will do the rest. They have used a bidirectional DC motor and solenoid valves to turn an ordinary Lazy Susan into a rotating platform system that could move a glass under inverted bottles and dispense liquids in a controlled manner, in order to make mixed drinks. A Atmega1284 MCU is used to control the liquid flow and its movement. The entire code is programmed using AVR studio and the language used is C. A feedback control loop and an IR sensor is used to track the position of the glass. The nozzles of the inverted bottles are attached to the valves, which are opened and closed by the microcontroller and hence used to control the flow of the liquid. A… Continue reading

Bluetooth based Pedometer

A pedometer is a device which counts the number of steps taken by the person by detecting the motion of the person’s hand. This project is a set of two device, a wrist device and the pedometer device. The pedometer device records the user steps and send it to a device mounted on the wrist using Bluetooth. On the wrist, the information is processed to obtain the user the steps they’ve taken, their pace, and the timing of their steps. Along with it, it also gives out the average speed. The pedometer utilizes ‘jerk’ which is nothing but derivative of acceleration with respective to time. By looking at the zero crossing of jerk from a positive to a negative value, the peak acceleration is obtained. This peak in acceleration corresponds to a foot hitting the ground or a foot rising very quickly from the ground. The MCU’s used in the project are Tiny Real Time kernel developed by Dan Henriksson and Anton Cervin at Lund University. However it has been modified by their instructor to run on Atmel AVR Mega1284… Continue reading

Infrared sensor based Theremin

Theremin is a device that allows playing music without touching the instrument. Basically Theremin is based on capacitance sensors where hands play ground plane role. By adjusting distance to the sensor you can change sound pitch and other parameters. Students Scott McKenzie and Alex Rablau from Cornell ECE4760 class build a bit different Theremin device where they used infrared distance sensors instead of capacitance. They used tow sensors – one for volume and another for pitch control. Atmega1284 reads both sensors and according to sound wave selection generates PWM modulated signal. They experimented with several waves including Classic theremin which is combined of two sine waves, then pure sine, sawtooth, and FM modulation. Each sound is great in its own way when played with “straight” hands. Continue reading

DIY 8-bit Computer on ATMega1284

This is an 8Bit computer which apart from being powered by an Arduino is also low cost. It also has a black and white LCD output along with a full QWERTY keyboard input. The brain of this computer is an Arduino ATMega1284 and majority of the files are stored in a 64KB EEPROM chip. It also has support to read and write data through serial interface. The new thing about this project which I found is that all the programs are written in a DPCL (Duo portable command language) for which 12KB of Ram has been reserved. DPCL consists of plain ASCII commands interpreted by the ATMega1284. DPCL programs are checked for syntax errors during runtime. The display is a 102×64 display which might seems small, but works perfectly. Also an online emulator has been provided to check different DPCl commands which is of great use for a beginner. For those interested in the project, everything from source code to hardware-description is available on the website along with some example programs that can be put to use right away. Continue reading