Software for Agobo

Python

You can download the latest python software: as a RAR file, or from GitHub

Alternatively, you can use the following commands from your Raspberry Pi in the home folder. (open LXTerminal from desktop):

• wget http://4tronix.co.uk/agobo.sh -O agobo.sh
• bash agobo.sh

 

Files included

• agobo.py This is the python library module, see the first few lines of the library for listing of all the exposed functions for controlling motors, LEDs and reading sensors
• motorTest2.py – use the arrow keys on your keyboard to control the direction and speed of the motors
• irTest.py – check the state of the IR line sensors
• sonarTest.py – print the distance using the UltraSonic sensor
• ledTest.py – flashes the white LEDs on Agobo. NOTE: This does not operate the neopixels on Agobo2, see the note below
• switchTest.py – shows the state of the mode switch once per second
• neopixel.py and strandtest.py – produce pretty patterns on the neopixel attached to PlusPlate and any extended ones see Adafruit’s blog for info

 

Setting up Agobo2 Neopixels

Before you can use the neopixels on Agobo2, you will need to install the necessary drivers. This is the same operation as for the PlayHAT, so let’s use the instructions for that. You can always move the files over to your Agobo folder afterwards

Ensure your Raspberry Pi is connected to the internet

$ sudo apt-get install git$ git clone https://github.com/4tronix/PlayHAT
$ cd ~/PlayHAT
$ sudo apt-get install python-pip python-dev
$ sudo python setup.py install

Now you can run the strandtest.py demo as follows:
$ sudo python strandtest.py

Specification

• Designed for Raspberry Pi Model A+ (Can also fit B+ and 2B using optional mountings)
• Pre-assembled. Only requires front caster, battery holder and Pi to be screwed on and then push the wheels on.
• Raspberry Pi plugs directly onto the main PCB
• Two N20 size metal geared motors fully and individually controllable in software
• Built in line-follower sensors with indicator LEDs
• Separately controllable front LEDs left and right (on Agobo2 these are fully addressable RGB neopixels)
• Power on/off switch and LED
• Connector for optional plug-in ultrasonic distance sensor
• Breakout header for a standard serial console cable (ideal way to program a headless Model A+)
• Breakout I²C header for our IP Display dongle
• Prototyping area to add your own sensors
• Fully replicated 40-pin GPIO header so you can attach your own addons
• Additional mounting holes to attach sensors or extra hardware

 

Optional Extras

• Ultrasonic sensors (HC-SR04) which simply plugs into the connector at the front
• Acrylic cover with mounting hardware to cover and protect the Raspberry Pi Model A+ (included as standard in Agobo2)
• PlusPlate™ Additional prototyping board and mounting hardware. This allows a full size area to add your own electronics from a simple LED, to more complex items including integrated circuits, RF modules and neopixels. See separate specification. The board comes complete with single, ready-wired, neoPixel with interface to extend to many, and a position for nRF24L01 socket
• Serial console cable which allows easy access to the Raspberry Pi command line without any setup required
• Super short micro USB cable to tidy up the battery connection
• Pre-loaded SD card with the latest Raspbian software and Agobo software (Python and Scratch)
• Wifi dongle
• Additional mounting accessories to enable mounting the Raspberry Pi B+ or Raspberry Pi 2 Model B

 

Software

• A Python library module and examples can be downloaded directly onto the A+ (if it has an internet connection) or transferred via USB stick or console cable
• ScratchGPIO supports Agobo as an Addon board type from release 6.xxx (TBD)

 

Links

• Purchase Agobo (opens in separate window)
• Walk through the Agobo features
• Assembly Instructions
• Software downloads
• Pre-release blog post (for interest only, specifications have changed)

 

Agobo with Ultrasonic sensor, WiFi dongle and short USB cable added to standard build

(Agobo2 has the Raspberry Pi turned 90 degrees so that fitting the B+ and 2B is possible)

Agobo – The Hackable Pre-Built Robot for the Raspberry Pi A+

Base Build

1. Pre-Built PCB with the following items pre-installed and ready to use
2. 2 x Metal geared Motors
   1. Left motor on physical GPIO pins 19 and 21
   2. Right motor on physical pins 24 and 26
3. Two InfraRed IR line sensors
   1. Left on physical pin 7 with Red indicator LED
   2. Right on physical pin 11 with Green indicator LED
4. Two White LEDs at the front (Agobo v1 only. On Agobo2 these are replaced by full addressable RGB neopixels)
   1. Left on physical pin 15
   2. Right on physical pin 13
5. Mode switch – or whatever you want to use it for on physical GPIO pin 16
6. Ultrasonic uses physical pin 23 for BOTH Ping and Echo. Swapping the direction of this pin is handled within the python library and ScratchGPIO
7. I2C pins broken out to 6-pin connector with 5v, 3.3V and Ground
8. Serial pins connected to a convenient 4-pin male connector so serial console cables plug right in (includes power and ground)
9. Fully replicated 40-pin GPIO connector and prototyping area with 5v, Ground and 3.3V strips for you to add your own sensors, LEDs, or whatever
10. All other pins free to do what you want

 

PlusPlate

1. Lots more prototyping area
2. Designed so ICs can fit in 4 different rows with easy access to 5V, Ground and 3V distribution lines
3. A great way of adding any sort of electronics
4. Use the Acrylic cover to safely protect your designs
5. Physical GPIO pin 12 is brought to a pre-fitted neopixel which is directly controllable in python (and ScratchGPOIO??)
6. Both the input and the output to the neopixel is brought to an expansion header so your pre-fitted pxiel can be in parallel with or in addition to the first pixel in your strip or ring of pixels
7. All unassigned GPIO pins (as well as 5V, 3.3V and Ground) brought to a separate row of accessible pads
8. A position for a standard nRF24L01+ module using SPI connections
9. With the PlusPlate™, the Agobo becomes infinitely hackable!

 

 Click on any image below to enlarge

*Note. Images still show the Agobo v1 build. Agobo2 is similar but rotated 90 degrees.

Basic Build

1. Check you have all the parts:

• Agobo ready built main board
• 2 rear wheels
• Front caster bag containing read-assembled caster
• Acrylic cover with “Agobo2” etched on
• Battery holder clip
• 16mm countersunk screw
• M3 nut
• 4 x 11 mm female-female pillars
• 8 x 6mm screws
• Battery with connector/charge cable
• 4 male-female pillars (5mm)
• 4 nylon washers

 

2. Fit the Front Caster

For Agobo2 this has already been done for you, so skip to Step 3

This is a fiddly task, but it is the only one. Once it is done, the rest is easy

Put the main ball in the housing, and the small balls into the “corners” as shown above

 

Put on the cover plate and hold it all together with your fingers, as you place it on the PCB

 

Then use the small (10mm) screws to fix it to the PCB.

That wasn’t so hard, right? (NB. If using the PlusPlate™, or wiring onto the replicated header pads, you will need to use the 3mm spacers and the longer screws – this is a much trickier operation)

 

3. Fit the Battery Holder

For Agobo2, the battery holder is fitted to the Acrylic plate, so skip to step 4

You will need the 5mm small acrylic plate, 20mm countersunk screw, M3 nut and the battery clip

 

Remove the backing plastic from the acrylic plate – it should be bright and transparent

Push the screw through from the top of the battery clip, through the acrylic plate, through the PCB and tighten the M3 nut underneath

 

4. Add the Mounting Pillars for the Pi

You will need the 4 female-female pillars (11mm) and the 8 screws (M2.5, 6mm)

 

Screw the 4 pillars into the PCB in the positions shown

 

5. Fitting the Acrylic Plate

 

6. Add the pillars

Screw the 5mm male-female pillars in to the 11mm pillars that hold the Raspberry Pi A+

 

3. Fit the Acrylic Cover

• Peel off the protective covering from the acrylic plate (now it is nice and shiny!)
• Screw the battery clip to the offset hole in the acrylic using the 16mm screws and M3 nut (the 5mm spacer acrylic piece is not required)
• Now use the 6mm screws with the nylon washers to hold the acrylic cover to the small pillars
• All done!

 

—–

Using with the PlusPlate

1. Check you have all the parts

To attach the PlusPlate you will have to do some light soldering.

First, fit the 2x20pin male headers to the main board as shown above

 

2. Re-Attach the Front Caster with spacers

Note: This is really tricky – take it carefully and patiently. There is a knack to doing it, which is described below, but it takes a few attempts before you can do it quickly.

You will need the longer screws and the 3mm spacers found in the bag with the front caster.

• Prepare the front caster as before and hold in one hand
• Hold the main PCB vertical (ie. resting on the back end (USB connector end)
• Put one long screw through the hole in the PCB
• Put a spacer over the screw so that it rests on it – remember, the screw is horizontal at this point. Gravity is your friend.
• Screw into the caster assembly with the other hole of the caster upwards(careful, though as it is easy to over-tighten)
• Now turn the caster into the correct position, and push the other spacer into position
• Then, screw the second screw in.
• Now, you can have a cup of coffee, or glass of wine, or whatever. You deserve it!

 

3. Add the Mounting Pillars

Use the 4 Male-Female 11mm pillars and screw each on in, holding the Pi in place

 

4. Prepare the PlusPlate

Solder the 40-way female header to the bottom of the PlusPlate

Push in the 40-way extended header

 

5. Connect the PlusPlate and Battery

Push the PlusPlate with extended headers into the male headers that you soldered onto the main PCB

 

Fix the PlusPlate with the 6mm screws (from the base build)

Add the battery clip to the PlusPlate using the 12mm countersunk screw

 

Fit the battery and off you go!

 

You can also add the Acrylic cover with the PlusPlate

Use the 5mm Male-Female pillars and mount the acrylic cover with the overhang at the front

Leave the battery clip fitted to the PlusPlate to reduce the overall height.