This document describes a snake robot project consisting of 8 linked modules with 16 servo motors. Each module has 2 servo motors and passive caster wheels. The snake robot is capable of 3D locomotion through terrain using pressure sensors for uphill and downhill motion. IR sensors enable collision-free movement. The robot can be controlled off-site using a PC connected via XBee modules. Real-time video is transmitted from the robot's wireless camera. Sensors on the robot detect environmental parameters and obstacles, while a microcontroller processes sensor data and controls motion.

1. George Rahul Paul (S7 A,17)
Meenu Saji (S7 B,28)
Titto Thomas (S7 A,47)
Tony Mohan Varghese (S7 A,48)
Vidya Sekhar (S7 B,50)

2. Snake Robots: What & Why ?
• Snake Robot -Multiple actuated joints implying multiple degrees of freedom.
• superior ability to flex, reach, and approach a huge volume in its workspace with
infinite number of configurations.
• Hyper redundant robots.
• Advantages of Serpentine Motion:
• Stability, Terrainability, Traction
• Redundancy, Modular structure.
• Applications
• Rescue and Military Operation
• Exploration, Inspection
• Medical
• Hazardous Environment

3. In scope
• 3D Locomotion
• Off site control using PC
• Real-time video transmission
• Obstacle avoidance during movement
• Environmental parameters detection and
analysis

4. 3D locomotion
• Snake robot consist of 8 modules with 2 servomotors
each
• Caster wheels (Passive) provided to compensate for the
friction coefficient
• Motions:
1)Terrain-adaptive locomotion
• Implemented by mechanical links, servomotor,
pressure sensor
• PWM signals from PIC to control servomotors
• Pressure sensors : proper up-hill and down-hill
motion
2) Collision-free Locomotion
• IR sensor for Collision-free path

5. Mechanical specification
SPECIFICATIONS DETAILS
Number of joints 16
Size of link(mm) 130x62x77
Weight of link(Kg) 0.28
Motion Range of joint(deg) [-90,+90]
Actuators Servo motor,
(FUTABA S3375 – 5Kg cm Stall Torque)
Sensors Pressure Sensor(INASTOMER)
IR sensor (SHARP GP2YOA710KOF)

6. Elements of control
• Servomotor : 16 such servomotors are used to
control motion
• Stall Torque :5Kg cm
• Operating voltage : 6V
• Micro-controller: DS PIC33FJ256GP710
•16 bit digital signal controller
•256KB flash memory
•Multichannel PWM
•2 UART Modules
•To generate 16 PWM signals to the servo
motors
•Processing of data from sensor and
monitoring motion of robot

7. Offsite control using PC
• XBEE : transmits data from snakes body to the PC and vice-versa for
motion control
Features:
•Operating Frequency:2.4 GHz
•1mW Wire Antenna
•Supply Voltage:3.3V @ 50mA
•Data Rate:250kbps (Max)
•Range of 30 meters indoor or 100 meters outdoor
• Data displayed on front – end VB User Interface

8. Real Time Video Transmission
• Wire-less Camera used for real-time video transmission
Features:
•1.2GHz Wireless Surveillance Camera Kit
•Operative range=150 feet
•Gives real time color video with zero delay
•380 lines resolution
•Power : 9V Battery or AC Adapter
• Based on video , control signals for micro-controller are generated

9. Obstacle Avoidance During Movement
• IR Sensor: For the obstacle-less motion of the robot and range determination
Features:
•Provides ambient light immunity
•IR LED and Photo Diode Pair
Environmental Parameters Detection and Analysis
• Temperature Sensor : LM 35
•Operating Range: -55°C to +150°C

10. Power Management
•On board Power Source:
•Lithium ion Polymer (Li Po)Battery pack - 7.4V,1600mAh
•LM 317-voltage regulator
• Output voltages – 5v,3.3v
•Battery Charging :
•LiPo charging SMPS
•LiPo Charging Chip
•MCP73831 : fully-integrated, single-cell, Li-ion/Li-
Polymer charge-management controller

11. Block Diagram
SENSORS
WIRELESS WIRELESS
CAMERA CAMERA
DSPIC RECEIVER
SERVO 33FJ256GP710
XBEE XBEE
MOTOR MAIN RECEIVER
TRANSMITTER
CONTROLLER
PC
GUI IN
BATTERY
VB
SNAKE ROBOT ON FIELD PC SIDE

12. How ?
• Analysis and display of sensor parameters
• Display of video in real time
PC • Software with GUI providing master control of the robot.
• Zigbee Modules on PC and Robot side
Wireless
• Highly secure one-to-one communication
• Sensors - IR, temperature,pressure
• 8 links, 16 servo motors.
Snake Robot • DSP onboard microcontroller with peripherals

13. Flow chart of communication

14. Thank You