UltraBorg - Precision servo control with ultrasonic module support

Installation

Images on this page may be clicked on to get a higher resolution and quality version.

Mounting

Two basic mounting options are provided:
The First option is to mount the board on top of a Rev 2 Raspberry Pi using the central mounting hole by positioning the board over the Raspberry Pi's mounting hole (the one closest to the HDMI connector), the board can be oriented however you choose.
The Second option is to mount the board using any combination of the three available mounting holes to part of the robot you are building, we recommend using all three if possible.
If stacking multiple boards using the mounting hole you will need to ensure the posts used provide enough clearance between boards so they cannot touch, if they are too close it may cause problems.

Connections

Here are all of the connections on the UltraBorg:

We will go through each type of connection separately below.
The first thing will be to connect the UltraBorg to your robot brain.

Raspberry Pi

Connect the six-pin header used for talking with the Raspberry Pi to the Raspberry Pi GPIO header as shown below.
The outlines show an individual 3x1 pin cable (two supplied), the coloured boxes show the colour of the wire (grey is used instead of black in the diagram).

As you can see you may connect multiple boards at once, read further down for instructions on configuring the software correctly to run with multiple boards attached.

Arduino

You only need to connect five pins to your Arduino to use UltraBorg.
These are IOREF (pin 1), SDA (pin 3), SCL (pin 5), 5V (pin 4), GND (pin 6).
SCL and SDA are on different pins for different Arduinos:

Arduino	SDA	SCL
Uno	A4	A5
Ethernet	A4	A5
Mega2560	20	21
Leonardo	2	3
Due	SDA1	SCL1

You may connect multiple boards at once by using the daisy-chain connector, simply connect two boards together using the 3x1 cables provided.
Read further down for instructions on configuring the software correctly to run with multiple boards attached.

Power

There are two options for power connection:

Connect a battery or 5v supply to the 2-pin screw terminal
If you are only using ultrasonics fit the 5V link jumper instead

You should NOT fit both the jumper and a battery, doing so may harm your control board!
Be careful to connect the battery the correct way around, fitting it backwards may damage servos or ultrasonic modules.

Servo motors

You may connect up to four servo motors to a single UltraBorg.
The servos connect on to the black 3-pin connectors shown above.
Make sure the connections match the UltraBorg correctly, not all servo manufacturers use the same colours or names.
- is known as -, -ve, 0v, GND, or ground. Often coloured black or brown.
+ is known as +, +ve, 5v, Vcc, or power. Usually coloured red.
S is known as S, signal, data, PWM, or position. Often coloured white or orange.
Consult your servo instructions to be safe.

Ultrasonic modules

UltraBorg is designed to work with the 4-pin HC-SR04 ultrasonic modules.
You may connect up to four ultrasonic modules to a single UltraBorg.
The ultrasonic modules connect on to the white 4-pin connectors shown above.
Make sure the connections match the UltraBorg correctly, connecting them incorrectly can damage the module
- is known as Gnd, on our 4-pin cables we use the white wire for this.
E is known as Echo, on our 4-pin cables we use the yellow wire for this.
T is known as Trig, on our 4-pin cables we use the black wire for this.
+ is known as Vcc, on our 4-pin cables we use the red wire for this.

Software

Raspberry Pi

Please note that this installation expects you to be connected to the internet, it will download i2c-tools and python-smbus for using I²C from Python, as well as tix for the tuning GUI.

You may need to enable I2C first, to do this:

Enter the following command in a terminal: sudo raspi-config
Move down to option 8 Advanced Options and press ENTER
Move down to option A7 I2C and press ENTER
Make sure Yes is highlighted and press ENTER
When the dialog says I2C is enabled press ENTER
Make sure Yes is highlighted again and press ENTER
When the dialog says I2C will be loaded by default press ENTER
Move right until Finish is highlighted, then press ENTER

If the I2C option is not available simply proceed to the next step.

To run through the automatic installer just use this one line in a terminal:
bash <(curl https://www.piborg.org/install-ultraborg.txt)
If you would prefer to manually run through the steps use the commands below:

mkdir ~/ultraborg
cd ~/ultraborg
wget http://www.piborg.org/downloads/ultraborg/examples.zip
unzip examples.zip
chmod +x install.sh
./install.sh

Manual download: http://www.piborg.org/downloads/ultraborg/examples.zip
At the end of the install two desktop icons will appear for the example GUI and the tuning GUI, you should now be ready to go.

Arduino

To get started first download the zip file: UltraBorg Arduino library and example sketch
Unzip the file to get the two provided sketches:
UltraBorgArduino - A simple example of using the UltraBorg.
UltraBorgTuning - A serial based example which allows you to tune the servo ranges.

The UltraBorgArduino example sketch contains the following:

UltraBorgTuning.ino - The example script which moves all the servos in a sequence
UltraBorg.h - The header for the UltraBorg library
UltraBorg.cpp - The UltraBorg library code itself

The UltraBorg library is all built on top of the Wire library, so any sketches using it should call Wire.begin(); before using the library, ideally in void setup().

Multiple Boards

In order to setup multiple boards there is an additional step, we need to give each board a unique address.
The allowable addresses are 3 (0x03) to 119 (0x77), the numbers in parenthesis are in hexadecimal.
The first task is to pick a unique number for each board, for this example we will have three boards which we will number 10, 11, and 12.

Raspberry Pi

Start the Raspberry Pi with the first board
Open a terminal and start a Python prompt as follows:
cd ~/ultraborg
python
Load the library
import UltraBorg
Set the address of the attached board, the function should tell you if this is successful or not
UltraBorg.SetNewAddress(10)
Disconnect the attached board and connect the next board, you can do this with the Raspberry Pi still running if careful, if you are worried shut the Raspberry Pi down first, then repeat the steps up to and including loading the library.
Set the address of the attached board, repeat the last two steps for each board.
UltraBorg.SetNewAddress(11)
UltraBorg.SetNewAddress(12)
Finally attach all of the boards at once, then run the following to see what addresses were found:
print UltraBorg.ScanForUltraBorg()
If everything went well the last line should show the numbers you set, e.g.
[10 11 12]
You can now use them all in a script like so

# Setup the library ready for use
import UltraBorg
# Board #1, address 10
UB1 = UltraBorg.UltraBorg()
UB1.i2cAddress = 10
UB1.Init()
# Board #2, address 11
UB2 = UltraBorg.UltraBorg()
UB2.i2cAddress = 11
UB2.Init()
# Board #3, address 12
UB3 = UltraBorg.UltraBorg()
UB3.i2cAddress = 12
UB3.Init()

Simply use UB1, UB2, or UB3 anywhere you would have used UB in a single board example.
You can use as many boards as there are free address numbers, over a hundred in all ^_^
For more detailed instructions or help see Setting up multiple UltraBorgs on the forum.

Arduino

To start make a new sketch, copy over the UltraBorg.c and UltraBorg.h into the same folder.
Paste the following code into the .ino file:

#include <Wire.h>               // The I2C library
#include "UltraBorg.h"          // The UltraBorg library

void setup()
{
    Wire.begin();               // Join the I2C bus (we will be acting as master)
    Serial.begin(9600);         // open the serial port at 9600 bps
}

void loop()
{
    int address;

    Ubi2cAddress = UbScanForAddress(0);
    UbInit();
    Serial.print("Current I2C address: ");
    Serial.println(Ubi2cAddress);

    Serial.println("Address to use ?");
    while (Serial.available() == 0) delay(100);
    address = Serial.parseInt();

    UbSetNewAddress(address);
    address = UbScanForAddress(0);
}

Upload the sketch, then open the serial monitor.
The script should report the current I2C address, the default is 54 (0x36).
Type in our new number, then press ENTER. If it worked the I2C address should now be the new number.
Disconnect the first UltraBorg, then connect the next one.
Press the reset button to get the Arduino to rescan the I2C bus.
Set this UltraBorg to the next number.
Repeat until they are all set.

If we have three boards set to 10, 11, and 12 we can talk to them like this:

#include <Wire.h>               // The I2C library
#include "UltraBorg.h"          // The UltraBorg library

void setup()
{
    Wire.begin();               // Join the I2C bus (we will be acting as master)
    Serial.begin(9600);         // open the serial port at 9600 bps
}

void loop()
{
    int address;

    Ubi2cAddress = 10;
    UbInit();

    Ubi2cAddress = 10;
    Serial.println("Distances board #1");
    Serial.println(UbGetDistance1());
    Serial.println(UbGetDistance2());
    Serial.println(UbGetDistance3());
    Serial.println(UbGetDistance4());

    Ubi2cAddress = 11;
    Serial.println("Distances board #2");
    Serial.println(UbGetDistance1());
    Serial.println(UbGetDistance2());
    Serial.println(UbGetDistance3());
    Serial.println(UbGetDistance4());

    Ubi2cAddress = 12;
    Serial.println("Distances board #3");
    Serial.println(UbGetDistance1());
    Serial.println(UbGetDistance2());
    Serial.println(UbGetDistance3());
    Serial.println(UbGetDistance4());
}

General Usage - Raspberry Pi

Example GUI

The example GUI provides a simple way of checking the servos and ultrasonic modules are working correctly.
The distance readings are filtered by the UltraBorg, the library provides access to both filtered and unfiltered distances.

You may notice that the servos are not able to use their whole range.
This can be corrected using the tuning GUI shown below.

Tuning GUI

The tuning GUI allows you to configure the range of movement for each servo attached to UltraBorg.
Not all servos use the same range of input, so to be safe UltraBorg uses a small range by default.

The tuning GUI allows you to configure three things for each servo:

The minimum allowed position
The maximum allowed position
The position to start at when powered

You may configure the servos to either operate to their widest possible range, or if you prefer only allow them to move for a smaller range.
See the UltraBorg tuning instructions for more detail on tuning your servos.

Other Examples

The following scripts may be run from the UltraBorg install folder (cd ~/ultraborg):
./ubReadDistances.py - Displays the ultrasonic distance readings
./ubSequence.py - Moves all four servos at different speeds
./ubServoFromDistances.py - Moves each servo based on the unfiltered ultrasonic readings
For more information or setup help see the full example details here.

Python Library

The example scripts make use of our Python library, UltraBorg.py, to command the board.
Filtered readings update slower then the unfiltered versions, but they are less noisy / jumpy.
The library exposes all of the features of the board with the following functions:

# Setup the library ready for use
import UltraBorg                        # Load the library
UB = UltraBorg.UltraBorg()              # Create a board object
UB.Init()                               # Setup the board

# Moving servos
UB.SetServoPosition1(position)          # Set the current position of servo #1
UB.SetServoPosition2(position)          # Set the current position of servo #2
UB.SetServoPosition3(position)          # Set the current position of servo #3
UB.SetServoPosition4(position)          # Set the current position of servo #4

# Reading the servo positions
UB.GetServoPosition1()                  # Read the current position of servo #1
UB.GetServoPosition2()                  # Read the current position of servo #2
UB.GetServoPosition3()                  # Read the current position of servo #3
UB.GetServoPosition4()                  # Read the current position of servo #4

# Reading distances
UB.GetDistance1()                       # Read the filtered distance from ultrasonic module #1
UB.GetDistance2()                       # Read the filtered distance from ultrasonic module #2
UB.GetDistance3()                       # Read the filtered distance from ultrasonic module #3
UB.GetDistance4()                       # Read the filtered distance from ultrasonic module #4
UB.GetRawDistance1()                    # Read the unfiltered distance from ultrasonic module #1
UB.GetRawDistance2()                    # Read the unfiltered distance from ultrasonic module #2
UB.GetRawDistance3()                    # Read the unfiltered distance from ultrasonic module #3
UB.GetRawDistance4()                    # Read the unfiltered distance from ultrasonic module #4

# Reading the servo limits
UB.GetServoMinimum1()                   # Read the minimum burst for servo #1 (divide by 2 for us)
UB.GetServoMaximum1()                   # Read the maximum burst for servo #1 (divide by 2 for us)
UB.GetServoMinimum2()                   # Read the minimum burst for servo #2 (divide by 2 for us)
UB.GetServoMaximum2()                   # Read the maximum burst for servo #2 (divide by 2 for us)
UB.GetServoMinimum3()                   # Read the minimum burst for servo #3 (divide by 2 for us)
UB.GetServoMaximum3()                   # Read the maximum burst for servo #3 (divide by 2 for us)
UB.GetServoMinimum4()                   # Read the minimum burst for servo #4 (divide by 2 for us)
UB.GetServoMaximum4()                   # Read the maximum burst for servo #4 (divide by 2 for us)

# Reading the servo startup positions
UB.GetServoStartup1()                   # Read the servo #1 startup burst (divide by 2 for us)
UB.GetServoStartup2()                   # Read the servo #2 startup burst (divide by 2 for us)
UB.GetServoStartup3()                   # Read the servo #3 startup burst (divide by 2 for us)
UB.GetServoStartup4()                   # Read the servo #4 startup burst (divide by 2 for us)

# Set the servo limits (we recommend doing this using the tuning GUI)
UB.SetServoMinimum1(pwmLevel)           # Sets the minimum burst size for servo #1 to pwmLevel / 2 us
UB.SetServoMaximum1(pwmLevel)           # Sets the maximum burst size for servo #1 to pwmLevel / 2 us
UB.SetServoMinimum2(pwmLevel)           # Sets the minimum burst size for servo #2 to pwmLevel / 2 us
UB.SetServoMaximum2(pwmLevel)           # Sets the maximum burst size for servo #2 to pwmLevel / 2 us
UB.SetServoMinimum3(pwmLevel)           # Sets the minimum burst size for servo #3 to pwmLevel / 2 us
UB.SetServoMaximum3(pwmLevel)           # Sets the maximum burst size for servo #3 to pwmLevel / 2 us
UB.SetServoMinimum4(pwmLevel)           # Sets the minimum burst size for servo #4 to pwmLevel / 2 us
UB.SetServoMaximum4(pwmLevel)           # Sets the maximum burst size for servo #4 to pwmLevel / 2 us

# Set the servo startup positions (we recommend doing this using the tuning GUI)
UB.SetServoStartup1(pwmLevel)           # Sets the startup burst size for servo #1 to pwmLevel / 2 us
UB.SetServoStartup2(pwmLevel)           # Sets the startup burst size for servo #2 to pwmLevel / 2 us
UB.SetServoStartup3(pwmLevel)           # Sets the startup burst size for servo #3 to pwmLevel / 2 us
UB.SetServoStartup4(pwmLevel)           # Sets the startup burst size for servo #4 to pwmLevel / 2 us

# Set the servo output to a specific burst time (we do not recommend doing this, it ignores set limits!)
UB.CalibrateServoPosition1(pwmLevel)    # Sets the PWM burst size for servo #1 to pwmLevel / 2 us
UB.CalibrateServoPosition2(pwmLevel)    # Sets the PWM burst size for servo #2 to pwmLevel / 2 us
UB.CalibrateServoPosition3(pwmLevel)    # Sets the PWM burst size for servo #3 to pwmLevel / 2 us
UB.CalibrateServoPosition4(pwmLevel)    # Sets the PWM burst size for servo #4 to pwmLevel / 2 us

# Get the current servo output burst time
UB.GetRawServoPosition1()               # Reads the current burst for servo #1 (divide by 2 for us)
UB.GetRawServoPosition2()               # Reads the current burst for servo #2 (divide by 2 for us)
UB.GetRawServoPosition3()               # Reads the current burst for servo #3 (divide by 2 for us)
UB.GetRawServoPosition4()               # Reads the current burst for servo #4 (divide by 2 for us)

# Setting parameters (before Init)
UB.i2cAddress = address                 # Set the address of the board to use
UB.printFunction = function             # Re-route / disable diagnostic messages

# Reading parameters (after Init)
print UB.busNumber                      # Shows which I²C bus the board is connected on
print UB.foundChip                      # See if the board is found / not found

# Other functions
UltraBorg.ScanForUltraBorg()            # Sweep the I²C bus for available boards
UltraBorg.SetNewAddress(address)        # Configure the attached board with a new address
UB.Help()                               # Get help on the available functions

For more complete details see the UltraBorg library reference.
To see the source code for the library or any of the examples see the code listings here.

General Usage - Ardunio

To get started open UltraBorgArduino.ino in the Arduino IDE with the UltraBorg and any servos / ultrasonics you wish to use attached.
Upload the sketch to the Arduino, the servos should begin moving in a repeating pattern.
To check the ultrasonics are working open the serial monitor and press the reset button.
Any attached ultrasonics should report a filtered position when the Arduino is reset.

If you wish to make your own sketch copy the library files into your sketch: UltraBorg.h and UltraBorg.cpp.
You will need to include the following libraries in your code:

// Import library headers
#include <Wire.h>                       // Load the I2C library
#include "UltraBorg.h"                  // Load the library

Before using the library make sure both of the above have been setup using these calls:

// Setup the libraries ready for use
Wire.begin();                           // Join the I2C bus (we will be acting as master)
UbInit()                                // Setup the board

You can then operate UltraBorg using the functions listed below.

You may notice that the servos are not able to use their whole range.
This can be corrected using the UltraBorgTuning example sketch.

Arduino Library

The example sketches make use of our Arduino library, UltraBorg.h, to command the board.
Filtered readings update slower then the unfiltered versions, but they are less noisy / jumpy.
The library exposes all of the features of the board with the following functions:

// Setup the library ready for use
#include <Wire.h>                       // Load the I2C library
#include "UltraBorg.h"                  // Load the library
Wire.begin();                           // Join the I2C bus (we will be acting as master)
UbInit()                                // Setup the board

// Moving servos
UbSetServoPosition1(position)           // Set the current position of servo #1
UbSetServoPosition2(position)           // Set the current position of servo #2
UbSetServoPosition3(position)           // Set the current position of servo #3
UbSetServoPosition4(position)           // Set the current position of servo #4

// Reading the servo positions
UbGetServoPosition1()                   // Read the current position of servo #1
UbGetServoPosition2()                   // Read the current position of servo #2
UbGetServoPosition3()                   // Read the current position of servo #3
UbGetServoPosition4()                   // Read the current position of servo #4

// Reading distances
UbGetDistance1()                        // Read the filtered distance from ultrasonic module #1
UbGetDistance2()                        // Read the filtered distance from ultrasonic module #2
UbGetDistance3()                        // Read the filtered distance from ultrasonic module #3
UbGetDistance4()                        // Read the filtered distance from ultrasonic module #4
UbGetRawDistance1()                     // Read the unfiltered distance from ultrasonic module #1
UbGetRawDistance2()                     // Read the unfiltered distance from ultrasonic module #2
UbGetRawDistance3()                     // Read the unfiltered distance from ultrasonic module #3
UbGetRawDistance4()                     // Read the unfiltered distance from ultrasonic module #4

// Reading the servo limits
UbGetServoMinimum1()                    // Read the minimum burst for servo #1 (divide by 2 for us)
UbGetServoMaximum1()                    // Read the maximum burst for servo #1 (divide by 2 for us)
UbGetServoMinimum2()                    // Read the minimum burst for servo #2 (divide by 2 for us)
UbGetServoMaximum2()                    // Read the maximum burst for servo #2 (divide by 2 for us)
UbGetServoMinimum3()                    // Read the minimum burst for servo #3 (divide by 2 for us)
UbGetServoMaximum3()                    // Read the maximum burst for servo #3 (divide by 2 for us)
UbGetServoMinimum4()                    // Read the minimum burst for servo #4 (divide by 2 for us)
UbGetServoMaximum4()                    // Read the maximum burst for servo #4 (divide by 2 for us)

// Reading the servo startup positions
UbGetServoStartup1()                    // Read the servo #1 startup burst (divide by 2 for us)
UbGetServoStartup2()                    // Read the servo #2 startup burst (divide by 2 for us)
UbGetServoStartup3()                    // Read the servo #3 startup burst (divide by 2 for us)
UbGetServoStartup4()                    // Read the servo #4 startup burst (divide by 2 for us)

// Set the servo limits (we recommend doing this using the tuning GUI)
UbSetServoMinimum1(pwmLevel)            // Sets the minimum burst size for servo #1 to pwmLevel / 2 us
UbSetServoMaximum1(pwmLevel)            // Sets the maximum burst size for servo #1 to pwmLevel / 2 us
UbSetServoMinimum2(pwmLevel)            // Sets the minimum burst size for servo #2 to pwmLevel / 2 us
UbSetServoMaximum2(pwmLevel)            // Sets the maximum burst size for servo #2 to pwmLevel / 2 us
UbSetServoMinimum3(pwmLevel)            // Sets the minimum burst size for servo #3 to pwmLevel / 2 us
UbSetServoMaximum3(pwmLevel)            // Sets the maximum burst size for servo #3 to pwmLevel / 2 us
UbSetServoMinimum4(pwmLevel)            // Sets the minimum burst size for servo #4 to pwmLevel / 2 us
UbSetServoMaximum4(pwmLevel)            // Sets the maximum burst size for servo #4 to pwmLevel / 2 us

// Set the servo startup positions (we recommend doing this using the tuning example)
UbSetServoStartup1(pwmLevel)            // Sets the startup burst size for servo #1 to pwmLevel / 2 us
UbSetServoStartup2(pwmLevel)            // Sets the startup burst size for servo #2 to pwmLevel / 2 us
UbSetServoStartup3(pwmLevel)            // Sets the startup burst size for servo #3 to pwmLevel / 2 us
UbSetServoStartup4(pwmLevel)            // Sets the startup burst size for servo #4 to pwmLevel / 2 us

// Set the servo output to a specific burst time (we do not recommend doing this, it ignores set limits!)
UbCalibrateServoPosition1(pwmLevel)     // Sets the PWM burst size for servo #1 to pwmLevel / 2 us
UbCalibrateServoPosition2(pwmLevel)     // Sets the PWM burst size for servo #2 to pwmLevel / 2 us
UbCalibrateServoPosition3(pwmLevel)     // Sets the PWM burst size for servo #3 to pwmLevel / 2 us
UbCalibrateServoPosition4(pwmLevel)     // Sets the PWM burst size for servo #4 to pwmLevel / 2 us

// Get the current servo output burst time
UbGetRawServoPosition1()                // Reads the current burst for servo #1 (divide by 2 for us)
UbGetRawServoPosition2()                // Reads the current burst for servo #2 (divide by 2 for us)
UbGetRawServoPosition3()                // Reads the current burst for servo #3 (divide by 2 for us)
UbGetRawServoPosition4()                // Reads the current burst for servo #4 (divide by 2 for us)

// Setting parameters (before UbInit)
Ubi2cAddress = address;                 // Set the address of the board to use

// Other functions
UbScanForCount()                        // Sweep the I²C bus for the number of available boards
UbScanForAddress(index)                 // Scans the I²C bus for an UltraBorg board, index is which address to return
UbSetNewAddress(address)                // Configure the attached board with a new address

For more complete details see the UltraBorg library reference.
To see the source code for the library or any of the examples see the code listings here.

Main menu

UltraBorg - Precision servo control with ultrasonic module support

Installation

Mounting

Connections

Raspberry Pi

Arduino

Power

Servo motors

Ultrasonic modules

Software

Raspberry Pi

Arduino

Multiple Boards

Raspberry Pi

Arduino

General Usage - Raspberry Pi

Example GUI

Tuning GUI

Other Examples

Python Library

General Usage - Ardunio

Arduino Library

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UltraBorg - Precision servo control with ultrasonic module support

Installation

Mounting

Connections

Raspberry Pi

Arduino

Power

Servo motors

Ultrasonic modules

Software

Raspberry Pi

Arduino

Multiple Boards

Raspberry Pi

Arduino

General Usage - Raspberry Pi

Example GUI

Tuning GUI

Other Examples

Python Library

General Usage - Ardunio

Arduino Library

Latest Blog

A robot called BOB

Tags:

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