A Lo calization T echnique bots F r o M ulti-Agent Prateek - PowerPoint PPT Presentation

A Lo calization T echnique bots F r o M ulti-Agent Prateek Humane and Neelay Trivedi R obot F ormations

What Di Did We Do Do? Indoor Localization System Arduino-Based Sensor Module Polygonal Formation Algorithm

HARD RDWARE RE

Sen ensor M Module O e Over erview Co Compass S ss Senso sor Xbee ee M Module e Pololu LSM303 compass Transmits a radio signal for sensor for absolute robot peer to peer and broadcast heading calculation (includes communication with the other accelerometer for data robots filtering) Ping ng S Sens nsor or Magnetic E Encoder ers Ultrasonic sensor with range Used in conjunction with the of 2cm to 3m. Every robot compass sensor for increased uses the ultrasonic receiver precision while turning except for the beacon robot that only uses the transmitters Low-Cost Model System Flexible sensor module under $50 new sensors = easy to add cross-environment capable

SOFTWARE

System em Overview ew Localization Formation Algorithm

Distanc nce Calcul ulation on

Putti tting it t all to together

D = R T * (speed of sound) (time of flight) Distance between robots

735 cm

81 cm

62 cm

60 cm

63 cm

67 cm

735 cm

The he C Coor oordina nate S System Master Workers 0 ° 30 ° 240 ° 40 cm

Wha hat’s the he P Poi oint nt of of the he L Loc ocalization on? Accurate Works Indoors Closed System 2 cm margin of error useful for close-range tasks Works in any environment

How ow D Doe oes I It Wor ork?

How ow D Doe oes I It Wor ork?

How ow D Doe oes I It Wor ork?

How ow D Doe oes I It Wor ork?

How ow D Doe oes I It Wor ork?

Wha hat is a a C Conv onvex Hull? (and nd why hy i it m matters rs) Reduces Complexity Motion Planning 3D Formations

Wha hat’s the he P Poi oint nt of of the he F For ormation on A Algorithm hm? Scalable Adaptable Extendable works for n robots works with any n-sided stepping stone for more regular polygon complex systems

Future Work mesh networks more robots! better algorithms relaying data quickly more fun! for cooler formations robot mapping add drones make it all faster for unknown environments ground-air coordination to improve response time

Why hy D Doe oes T Thi his Matter?

Quest stions

Appe pendi dix

Pol olar Coor oordina nate Math

Mor ore on on Conv onvex Hulls

XBee Radio Module Networ orking P g Prot otoc ocol ols Specifications Broadcasting Series 1 model 1714 Peer to Peer 27mm x 24mm x 9mm 5v power module Switching b bet etween een networ ork pr prot otoc ocol ols Microcontroller interface Allows you to switch Uses Serial to between the communicate protocols in code with Arduino using AT commands Setup Network I ID Easy to wire due to Serial communications. Can be identified by Simple to setup network unique address under logistics using XCTU a specified operating (software provided by Digi) channel

Parallax Ping Sensor ● Uses ultrasonic transmitter(on the right) and a receiver (eye on the left) to measure distance ● 2 cm to 3 m range ● Led flickers to show when burst is sent ● 3 pins (data, power and ground) ○ Uses data line that can be set to Receiver Sender high or low to measure distance or to send ultrasonic burst Ultrasonic sensor sends a ping from the right and measures the time it takes until the left ping receives the ultrasonic burst.

LSM303 Compass Sensor I2C device Uses an accelerometer in addition to the magnetometer to compensate for sudden movements Mounted higher up on standoffs so that the electromagnetic field from the motors doesn’t interfere with the compass magnetometer Returns a heading in degrees relative to north

Sensor Module Compass Sensor Overview Pololu LSM303 compass sensor for absolute robot heading calculation (includes Cost-Efficient accelerometer for data filtering) Xbee Radio Module Our prototyped sensor model was under $70. However, since we used Transmits a radio signal for Parallax Ping Sensors that we peer to peer and broadcast already owned and not generic 4-pin communication with the other sensors, our true cost is actually robots under $50. Closed System Parallax Ping Sensor Ultrasonic sensor with range of 2cm to 3m. Every robot uses Cross-environment functionality, no need the ultrasonic receiver except to communicate with outside for the beacon robot that only technologies like GPS, satellite, etc; uses the transmitters Indoor Accuracy Magnetic Encoders Margin of error under 2 cm indoors, unlike Used in conjunction with the GPS and other methods compass sensor for increased precision while turning

Formation Algorithm Overview/Flowchart After each robot’s relative polar coordinate has been calculated, each robot is assigned a new point in space to travel to and the robot formation is constructed. ● Finding the convex hull of the shape formed by the robots guarantees that the resulting shape will be non self-intersecting and that its centroid will lie inside the area bounded by its edges. ● The centroid of the shape is not necessarily the point assigned to the beacon robot: rather, point assignment is based upon ranking distances sequentially. Therefore, minimum distances to the target and maximized and maximum distances to the target are minimized, thus optimizing the distance each robot must travel to reach its target.