This paper describes the design of a simple, low-cost microcontroller based heart rate measuring device with LCD output. Heart rate of the subject is measured from the finger using sensors and the rate is then averaged and displayed on a text based LCD.
The LCD of the heart beat monitor shows the beat per minute.The sensor part consists of sensing elements,LDR(light dependent resistor) and LED(light emitting diode),a comparator module,a low pass filter.Heart beat is sensed by the sensing elements and the comparator produces an amplified square wave output.The comparator output is given to a low pass filter and the filter output is fed to one of the digital inputs of PIC 16F877a type micro controller. The micro controller output ports drives the LCD.
This paper describes the design of a very low-cost device which measures the heart rate of the subject by clipping sensors on one of the fingers and then displaying the result on a text based LCD. Advantage of such a design is that it can be expanded and can easily be connected to a recording device or a PC to collect and analyse the data for over a period of time.
Accelerometers can be used for measuring both dynamic and static measurements of acceleration.The objective of our project is to “design a PIC board which can sense which direction we are moving our hand and then control a toy car with it”. This is implemented with the help of accelerometer. The design has a microcontroller which is the heart of the circuit, an accelerometer used as a tilt sensor, a driver IC and dc motors.
The movement represents different operations such as forward, reverse, left and right. By using this mechanism we move a toy car, by the tilt of accelerometers.
The printed circuit board of our toy car is loaded with several units such as microcontroller, TILT Sensor, driver circuit and motors. Microcontroller is the heart of the circuit. The microcontroller used is PIC 16F877a. It is a flash type reprogrammable memory. It also provides sufficient power to inbuilt peripheral devices .The system used here is embedded systems.
The application of this system makes user friendly cheaper solutions and enables to add features otherwise impossible to provide other means. The software used for the embedded system is called firmware. The language used is pic c.
Our project uses an accelerometer to control movements of a toy car based on the acceleration given, which depends on gravity.