Accelerometer Controlled Robot

Transcription

1 Volume-6, Issue-2, March-April 2016 International Journal of Engineering and Management Research Page Number: Accelerometer Controlled Robot Ajay Naugain 1, Dharmendra Choudhary 2, Dharmveer Jyani 3, Kamal Kumar 4, Baibhav Bishal 5 1,2,3,4 Student, Department of Electrical Engineering, S.K.I.T, Jaipur, INDIA 5 Lecturer, Department of Electrical Engineering, S.K.I.T, Jaipur, INDIA ABSTRACT Generally, robots are programmed to perform specific tasks which humans cannot. To increase the use of robots where conditions are not certain such as fire fighting or rescue operations, robots can be made which follow the instruction of human operator and perform the task. In this way decisions are taken according to the working conditions by the operator and the task is performed by the robots. Thus, we can use these robots to perform those tasks that may be harmful for humans. This paper describes about the gesture control robot which can be controlled by your normal hand gesture. It consists of mainly two parts, one is transmitter part and another is receiver part. This combination of transmitter and receiver is known as RF module. The transmitter will transmit the signal according to the position of accelerometer and your hand gesture and the receiver will receive the signal and make the robot move in respective direction. Keywords---- Accelerometer, RF Modules I. INTRODUCTION In recent years, robotics is a current emerging technology in the field of science. A number of universities in the world are developing new things in this field. Robotics is the new booming field, which will be of great use to society in the coming years. Though robots can be a replacement to humans, they still need to be controlled by humans itself. Robots can be wired or wireless. Both have pros and cons associated with them. Beyond controlling the robotic system through physical devices, recent method of gesture control has become very popular. The main purpose of using gestures is that it provides a more natural way of controlling and provides a rich and intuitive form of interaction with the robotic system. These days many types of wireless robots are being developed and are put to varied applications and uses. Human hand gestures are natural and with the help of wireless communication, it is easier to interact with the robot in a friendly way. The robot moves depending on the gesture made by your hand and from a distance. The objective of this paper is to build a wireless gesture control robot using accelerometer, RF transmitter and receiver module. According to the tilt of the accelerometer sensor mounted on hand, it sends the commands to the RF transmitter which is received by the transmitter and is processed at the receiver end which drives the motor to a particular direction. The robot moves forward, backward, right and left when we tilt our palm to forward, backward, right and left respectively. The robot stops when it is parallel to the ground. 407 Copyright Vandana Publications. All Rights Reserved. II. LITERATURE SURVEY The emergence of service robots in early 90 s (Helpmate Robots and Robo-Caddy) followed by the development of natural language interface through keyboard has been given by Torrance in 1994[1]. Speech recognition evolved as an upgradation of the past work to communicate with machines but it lacked the standardization of commands due to varying languages, pitch and accent of different users. Hence, researchers [1]- [2] proposed vision-based interface that included gesture recognition through camera to provide geometrical information to the robots. They developed mobile robot systems that were instructed through arm positions but those robot systems couldn t recognize gestures defined through specific temporal patterns. Other limitation faced by the cameras was the poor illuminations at night and in foggy weather [3]-[4]. Motion technology facilitates humans to interact with machines naturally without any interventions caused by the drawbacks of mechanical devices. Using the concept of gesture recognition, it is possible to move a robot accordingly [5]. Gyroscope and Accelerometers are the main technologies used for human machine interaction

2 that offer very reasonable motion sensitivity, hence, are used in large array of different applications [6]. A lot of work has been done on motion technology using accelerometers [7]. In 2008, Chinese traffic police system used two 3-axis accelerometers fixed on the back of their arms that were synchronized with traffic lights. However, data could only be extracted while the arms would be steady [3]. In 2010, Sauvik Das et al have used an accelerometer as a potential spying device to show locations and activities of user without one s knowledge [8]. III. COMPONENTS USED L293D Motor Driver The L293 and L293D are quadruple high-current half-h drivers. The L293 is designed to provide bidirectional drive currents of up to 1 A at voltages from 4.5 V to 36 V. The L293D is designed to provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V. Both devices are designed to drive inductive loads such as relays, solenoids, dc and bipolar stepping motors, as well as other high- current/highvoltage loads in positive-supply applications. All inputs are TTL compatible. Each output is a complete totem-pole drive circuit, with a Darlington transistor sink and a pseudo-darlington source. On the L293, external highspeed output clamp diodes should be used for inductive transient suppression. A VCC1 terminal, separate from VCC2, is provided for the logic inputs to minimize device power dissipation. The L293and L293D are characterized for operation from 0C to 70C. Fig.1 Pin Diagram of L293D ADXL335 Accelerometer Moodule The ADXL335 is a small, thin, low power, complete 3-axis accelerometer with signal conditioned voltage outputs. The product measures acceleration with a minimum full-scale range of ±3 g. It can measure the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion, shock, or vibration. The user selects the bandwidth of the accelerometer using the CX, CY, and CZ capacitors at the XO UT, YOUT, and ZOUT pins. Bandwidths can be selected to suit the application, with a range of 0.5 Hz to 1600 Hz for the X and Y axes, and a range of 0.5 Hz to 550 Hz for the Z axis. Table 1. Features of ADXL335 Accelerometer Axis 3-Axis Sensing Profile Small, low profile package Size 4 mm 4 mm 1.45 mm LFCSP Power Low 350 μa (typical) Single-supply Operation 1.8 V to 3.6 V Shock Survival 10,000 g Temperature Stability Excellent Bandwidth BW adjustment with a single capacitor per axis Other RoHS/WEEE lead-free compliant Fig. 2 ADXL335 Accelerometer HT12D Decoder HT12D IC comes from HolTek Company. HT12D is a decoder integrated circuit that belongs to 212 series of decoders. It is mainly provided to interface RF and infrared circuits. They are paired with 212 series of encoders. The chosen pair of encoder/decoder should have same number of addresses and data format. In simple terms, HT12D converts the serial input into parallel outputs. It decodes the serial addresses and data received by, say, an RF receiver, into parallel data and sends them to output data pins. The serial input data is compared with the local addresses three times continuously. The input data code is decoded when no error or unmatched codes are found. A valid transmission in indicated by a high signal at VT pin. HT12D is capable of decoding 12 bits, of which 8 are address bits and 4 are data bits. 408 Copyright Vandana Publications. All Rights Reserved.

3 of encoder and decoder. It can transmit the signal up to 500 ft of range at rate of 1 Kbps to 10 Kbps. Fig. 5 RF Module. Fig. 3 Pin Diagram of HT12D Transmitter module consists of 4 pins (GROUND, VCC, DATA, ANTENNA). DATA pin is connected to encoder (pin 17). A 17 cm single strand wire antenna is used which is connected to antenna pin of Tx module. Transmitter receives serial data and transmits RF signal wirelessly to the receiver through this antenna. HT12E Encoder HT12E is an encoder integrated circuit of 212 series of encoders. They are paired with 212 series of decoders for use in remote control system applications. It is mainly used in interfacing RF and infrared circuits. Simply put, HT12E converts the parallel inputs into serial output. It encodes the 12 bit parallel data into serial for transmission through an RF transmitter. These 12 bits are divided into 8 address bits and 4 data bits. When a trigger signal is received on TE pin, the programmed addresses/data are transmitted together with the header bits via an RF or an infrared transmission medium. HT12E begins a 4-word transmission cycle upon receipt of a transmission enable. This cycle is repeated as long as TE is kept low. As soon as TE returns to high, the encoder output completes its final cycle and then stops. Fig. 6 Pin Diagram of RF Transmitter Receiver module consists of 8 pins. 3 ground pins, 2 VCC pins, 2 DATA pins and 1 antenna pin. DATA pins are connected to decoder (pin 14). In this module also, a 17 cm single strand wire antenna is used for receiving RF signal from transmitter. Fig. 7 Pin Diagram of RF Receiver DC Motors Fig. 4 Pin Diagram of HT12E RF Transmitter And Receiver Module RF stands for radio frequency[1][13]. It is available in different operating frequencies and with different operating range. We have used 433 MHz RF Tx/Rx module. RF module is often used along with a pair Fig. 8 DC Motor 409 Copyright Vandana Publications. All Rights Reserved.

4 This is a low cost DC motor suitable for most robotic and general applications. It has a output shaft with a hole for easy mounting of wheels or pulleys. Table 2. Details about DC Motors Output RPM 200 rpm Input Voltage 12 V Stall Current Ma Shaft length 2.4 IV. CIRCUIT DIAGRAM An Accelerometer Controlled Robot is a kind of robot which can be controlled by hand gestures not by old buttons. The ADXL335 accelerometer sensor act as the input device which is mounted on a PCB, DC Motor Driver act as the driver for the motors connected to the Robot, and RF link acts as a channel for wireless communication. They sends the command to RF transmitter which is Received by the receiver and send signal to the motor driver which drives the motors in forward, reverse, left, right direction and stops it. The Robot moves in forward, reverse, left, right direction and stops when the hand tilts in forward, backward, left, right direction and not tilted respectively. The direction of the Robot changes if the connection of motors to the DC Motor Driver and the accelerometer sensor direction of mounting are changed. The transmitting device included an ADC for analog to digital conversion and an encoder IC (HT12E) which is use to encode the four bit data and then it will transmit by an RF Transmitter module. At the receiving end a RF Receiver module receives the encoded data and decodes it by decoder IC (HT12D). This data is then used to finally work our motor driver to control the motors. Now, its time to break the task in different modules to make easy and simple. Also, any project becomes easy or error free if it is done in different modules. Hence, we divide our project into two different parts that is transmitter side and receiver side. movement, backward movement, moves towards right and moves towards left. Stop Condition When the accelerometer is parallel to the horizontal plane, all the output pins of decoder (13, 12, 11, 10) are set to high which makes the robot in stop mode. Forward Movement When the accelerometer is tilted to forward, two output pin of decoder (13, 11) are set to low and other two output pin of decoder (12, 10) are set to high. This condition commands the robot to move in forward direction. Backward Movement When the accelerometer is tilted towards backward direction, two output pin of decoder (12, 10) are set to low and other two output pin of decoder (13, 11) are set to high. This condition commands the robot to move in backward direction. Right Movement When the accelerometer is tilted towards right, two output pin of decoder (12, 11) are set to low and other two output pin of decoder (13, 10) are set to high. This condition commands the robot to move towards right. Left Movement When the accelerometer is tilted towards left, two output pin of decoder (12, 11) are set to high and other two output pin of decoder (13, 10) are set to low. This condition commands the robot to move towards left. VI. COMPARISONS WITH EXISTING SYSTEM The major advantage of this system over other systems is that it provides real time palm gesture recognition, leading to an effective and natural way of controlling robots. Additional advantage-- many existing system have used Bluetooth wireless control which is replaced by RF modules in this paper, and due to which the range has been enhanced. VII. CONCLUSION Fig. 9 Block Diagram of Accelerometer Controlled Robot V. WORKING The transmitter prototype is kept on the palm and the receiver prototype ( i.e robot) moves according to the palm movement. This paper explains about the 5 different gesture position of the hand i.e stop condition, forward In this paper, an automated robot has been developed which works according to your hand gesture. The robot moves wirelessly according to palm gesture. The RF module is working on the frequency of 433 MHz and has a range of meters. This robot can be upgraded to detect human life in earthquake and landslide by implementing the sensor accordingly. It can also be upgraded to bomb detecting robot as it has robotic arm it can also lift the bomb. GPS system can be added to the robot by the help of which its location can be tracked. VIII. FUTURE SCOPE OF ACCELEROMETER BASED ROBOT 410 Copyright Vandana Publications. All Rights Reserved.

5 1. Sign language recognition 2. For socially assistive robotics 3. Directional indication through pointing 4. Control through facial gestures 5. Alternative computer interfaces 6. Immersive game technology 7. Affective computing 8. Remote control REFERENCES [1] Waldherr, S., Thrun, S., and Romero, R., A Gesture based interface for Human-Robot Interaction, Kluwer Academic Publishers, Netherland, [2] Liu, T., Guo, H., and Wang, Y., A new approach for color-based object recognition with fusion of color models, Congress on Image and Signal Processing Conference, Sanya-China, vol. 3, pp , May [3] Wang, B., and Yuan, T., Traffic Police Gesture Recognition using Accelerometer, IEEE SENSORS Conference, Lecce-Italy,pp , Oct [4] Lalanne, T., and Lempereur, C., Color recognition with a camera: a supervised algorithm for classification, IEEE Southwest Symposium on Image Analysis and Interpretation, Tucson-Arizona, pp , April [5] Available: [6] Cannan, J. and Hu, H., Human-Machine Interaction (HMI): A Survey.[Online]. Available: 508%20HMI-Survey.pdf [7] Das, S., Toya, L., Green, Perez, B., and Murphy, M. M., Detecting User Activities using the Accelerometer on the Smartphone, Team for Research in Ubiquitous Secure Technology REU Research Program, July [8] Song, M., Kim, B., Ryu, Y., Kim, Y., and Kim, S., A design of real time control robot system using android Smartphone The 7th International Conference on Ubiquitous Robots and Ambient Intelligence (URAI), Busan-Korea, Nov [9] SwarnaPrabha Jena, Sworaj Kumar Nayak, Saroj Kumar Sahoo, Sibu Ranjan Sahoo, Saraswata Dash, Sunil Kumar Sahoo, ACCELEROMETER BASED GESTURE CONTROLLED ROBOT USING ARDUINO, IJESRT, April, [10] Monika Jain, Aditi, Ashwani Lohiya, Mohammad Fahad Khan, Abhishek Maurya, WIRELESS GESTURE CONTROL ROBOT: AN ANALYSIS, International Journal of Advanced Research in Computer and Communication Engineering Vol. 1, Issue 10, December Copyright Vandana Publications. All Rights Reserved.