TourRobot
| TourRobot | |
|---|---|
| Primary Contact | Matt Little |
| 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: