Difference between revisions of "TourRobot"

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*Listen for the echo reply. The time it takes is a direct indication of how far away the object is. Sound travels at 343.2m/s at sea-level and at 20C.
 
*Listen for the echo reply. The time it takes is a direct indication of how far away the object is. Sound travels at 343.2m/s at sea-level and at 20C.
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Additional ICs which do the ultrasonic stuff includes:
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Revision as of 19:45, 22 January 2014

TourRobot
[[{{{image}}}|border|frameless|220px|center]]
Primary Contact Matt Little
Created {{{created}}}
Completed {{{completeddate}}}
Dormant {{{dormantdate}}}
Version {{{version}}}
Members {{{members}}}
Manufacturer {{{manufacturer}}}
Model {{{model}}}
Location [[{{{location}}}]]
GitHub / Repo {{{repo}}}
Status {{{status}}}
Type Undefined
Live Status {{{livestatus}}}
QR code

Giving tours around the hackspace takes time and effort. So the obvious solution is to build a robot to do it. Here are the details and build log.

Start 27/11/13 Basic base is the blue robot from Real Robots Magazine. I got this from a car boot sale and, at the first Arduino 101 day I fixed my arduino base to the robot. There is loads of detail on the Lpilsley Cybot here.

The Arduino is a Duemilanova with an ATMega328. I might upgrade to an Uno if needed.

The motor control unit has been left in to power the motors. Details on the circuit diagram are here.

An audio module MOD-1007 from Embedded Adventures has been added for the tour audio. This uses 3v3, which is taken from the Arduino, although for high volumes this does not have enough current. A seperate regulator might be required. Follow the data sheet to see how to play different files using the serial data lines.

Distance is found using ultrasonic sensors re-purposed from the original Real Robot. These have circuit diagrams here.There is a load more information on how the Ultrasonic sensors (called the "sonar board") works here.


There is also a line follower with a circuit diagram here.



Arduino Pins

Digital:

0 -> Rx

1 -> Tx

2 -> Motor 1 Forward

3 -> Motor 1 Backward

4 -> Motor 2 Forward

5 -> Motor 2 Backward

6

7

8

9

10

11 -> RESET Sound Module

12 -> CLOCK Sound Module

13 -> SDATA Sound Module


Analog

A0 -> LDR 1

A1 -> LDR 2

A2

A3

A4

A5

Ultrasonic sonar distance measuring

Using the Cybot Sonar Board.

The microcontroller needs to output 8 pulses, each of 12.5uS length. Period is 25mS, which is an output frequency of 40kHz. Output is generated every 25mS.

On the Sonar Board:

  • Pins 5/6 are for the piezo outputs.
  • Pins 2/3/4 requie 10k pull-ups.
  • Pins 2/3 are left/right input gating.
  • Pin 4 is the output

The concept is:

  • Send a short blast of 40kHz output.
  • Wait a short while (so we dont pick up the signal due to the Tx/Rx being very close to each other).
  • Listen for the echo reply. The time it takes is a direct indication of how far away the object is. Sound travels at 343.2m/s at sea-level and at 20C.


Additional ICs which do the ultrasonic stuff includes: