Design and Fabrication of Voice Activated Robotic Arm – Mechanical Project

Abstract – The aim of the project is to design and fabricate the voice activated robotic arm. The voice activated robotic arm is a robotic arm that works by means of the voice recognition mechanism. The Robotic arm obeys the voice commands and it works accordingly. A suitable microcontroller must be selected in order to accomaplish the task.The fabrication is done by using the arduino microcontroller incorporating the speech module. Designing will be done by using CATIA software. The project work will be beneficial to the handicapped persons, who are unable to move their hands. The voice activation is one of the advanced technologies. The fabrication is done by the incorporating a microcontroller along with a speech module. The received voice is identified and the voice signals are quantified, sampled and the discretization process take place. Hence the noise signals are rectified by the sampling process. The voice commands are processed and it is converted to text commands. The stepper motor and other devices works based on the voice signals and the text commands.

INTRODUCTION
The robotic arm is a prototype, similar to the human arm. It is commonly controlled by the computer programs. A robotic arm consists of links and joints which is controlled by the actuators like servo motors and gears. The arm may be the sum total of the mechanism or may be part of a more complex robot. The links of such a manipulator are connected by joints allowing either rotational motion (such as in an articulated robot) or translational (linear) displacement. The links of the manipulator can be considered to form a kinematic chain. The terminus of the kinematic chain of the manipulator is called the end effectors and it is analogous to the human hand. The robotic arm will be having a robotic hand at the end for performing certain task according to the situations. The common task of the robotic end effector include grasping, welding ,detecting etc.
In this project, the concept of voice actuation is introduced .The robotic arm works according to the voice commands. Voice comes under the field of artificial intelligence. In this project designing and fabrication of the 4 degrees of freedom robotic arm will be done.

Speech Recognition
Voice actuation is one of the artificial intelligence techniques used in the robotics. In robotics speech recognition is the transformation of the voice signals in to the text commands. The process by which the machine identifies the words is speech recognition. Speech recognition is the method by which a device or controller (or any type of arrangement) identifies the verbal words. It simply means ordering to device and it exactly recognizes the voice instruction given.
Speech Recognition is an ability of computer software program or hardware mechanism to decode the human command into digitized speech that can be interpreted by the computer or hardware device. Voice recognition is commonly used to operate a device, perform commands, or
to command robot to pick items or to do a certain work.

There are 2 important steps in speech recognition.
1) Recognize the sound excluding the noise and
2) Identifying the words from that sound.

The speech recognition technique also depends on the parameters like the speaking mode, language and the style of speaking. In this proposed project a speech recognition hardware module will be installed to accomplish the task. The main objective of speech recognition technique is to interpret a phrase or words by using the microphone and transform it in to the text commands.

THEORY
Speech Recognizers (SR) can be used to facilitate communication between humans and machines. Speechbased, human-machine interaction is demonstrated in several everyday applications. SR systems have been designed for different applications, in many areas, under a combination of restrictions, such as specific language and vocabulary, speaker dependency, noise-free environments and low talking rates, with excellent results. Software analysis, designing and implementation are the basic steps required to develop the theoretical system. Based
upon this analysis a hardware model is developed, which first recognize the voice or command and then with the help of microcontroller based embedded system, movement of motor driven robotic arm is controlled.
Complete analysis is divided into two, software and hardware for the implementation. In the first step, the designing is carried out using computer package (CATIA/ANSYS). Second step is to fabricate the hardware of the prototype of the motor driven robotic arm. After completion, the system was tested on the different loads. Durability of the system was checked for respective loads.

Design and Fabrication of Voice Activated Robotic Arm

Arduino Microcontroller
The Arduino Uno is a microcontroller board based on the ATmega328. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with an AC-to-DC adapter or battery to get started. The Uno differs from all preceding boards, in that it does not use the FTDI USB-toserial driver chip.

LCD Display Unit
A liquid crystal display (LCD) is an electro-optical amplitude modulator realized as a thin, flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or reflector. It is often utilized in battery powered electronic devices because it uses very small amounts of electric power. The LCDs have a parallel interface, meaning that the microcontroller has to manipulate several interface pins at once to control the display.