Monday, 29 August 2016

UFO detects light

In a previous post (UFO has Landed)  I started playing with the CBiSEducation's UFO Consumable Robotics. Now I am going to play with it a bit more and add the light sensor, included in the kit, to it;is so it can detect different light levels. Again it is controlled using the Micro:Bit.

Stage 1 - Decorating it
The kit comes with some stickers so I added a few.

Stage 2 Wiring
Pins 0 and 1 are outputs to the LEDs
Pin 2 is the input from the light sensor
The red lead from the light sensor connects to 3v and the grounds to the ground.


Stage 3 Code

The light sensor works more as a low light level detector, the darker the higher the value returned (in this case) on pin 2. So in low light level,  the LEDs flash relatively quickly, when the light level rises half of the LEDs start to pulse more slowly.






All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with.

Tuesday, 23 August 2016

UFO has landed

CBiS Education generously sent me two of their new range of robotics development kits - BinaryBots (https://www.binarybots.co.uk/makers.aspx), these are a range of cardboard based kits (so far a robot and a UFO) with electronic components for example LEDs; sensors and buzzers,  depending on the kits. What makes the kits interesting though is they are designed to be controlled by either by a BBC Micro:bit or a CodeBug.

This blog documents, briefly, an initial play with the UFO kit (see below) using a Micro:Bit for control. 


The UFO model came together readily, the instructions were fairly easy to follow. Personally, a feature I especially liked about the model was the LEDs being both on the top and bottom of it - increasing its usefulness. CBiS EducationThey have also provided a webpage / portal with some example projects and code. 




My first project I built, was to pulse the LEDs on and off (one set of LEDs on Pin 0, the other on Pin 1). Pin 2 was connected to the buzzer, so produce a low buzz every few seconds. The code below is written using the Block Editor (https://www.microbit.co.uk/create-code)

The video below shows the LEDs pulsing. I do need to decorate the UFO though!




Looking forward to playing with it further.

Related
http://robotsandphysicalcomputing.blogspot.co.uk/2016/08/ufo-detects-light.html


All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with.

Friday, 19 August 2016

Micro:bit Junkbot for use in schools


A new direction has been developed for the junkbot project (http://junkbots.blogspot.co.uk/); previously Raspberry Pis have been used to control the junkbot’s movement (http://robotsandphysicalcomputing.blogspot.co.uk/2016/01/python-junkbot.html) – but what about the recently released Micro:Bits; can it be used to control a junkbot?

Matthew Hole, a student from Wrenn Academy, Northamptonshire ; has been investigating this idea whilst on a Nuffield Research Placement (http://www.nuffieldfoundation.org/nuffield-research-placements) working with Dr Scott Turner, University of Northampton. The project was to look into developing junkbots controlled using a Micro:bit and also to produce some materials for schools to use with or without outside assistance.






What is a Junkbot?
For this project, it is a moving ‘bot’ made from waste materials, combined with an electric motor and a programmable device (in this case a Micro:Bit) to control (or try) it. An example is shown above. More details on junkbots can be found at http://junkbots.blogspot.co.uk/


Approach used in the project.
A Micro:Bit was selected for two reasons. First, there was been a BBC supported project to give year 7 (or equivalent) students a Micro:bit (http://www.bbc.co.uk/programmes/articles/4hVG2Br1W1LKCmw8nSm9WnQ/the-bbc-micro-bit), so they are available in the schools. Secondly, Kitronik produce a motor driver board, and provide quite a bit of support for it, for the Micro:Bit (the latest version of the board can be found at https://www.kitronik.co.uk/5620-motor-driver-board-for-the-bbc-microbit-v2.html ). Using Micropython via the online editor https://www.microbit.co.uk to program the board and therefore the junkbot connected. The board with the Micro:Bit attached can be seen in the figure above carried on the junkbot.

An example piece of code is shown below:

from microbit import *

def startIt():
   pin8.write_digital(1)
   pin12.write_digital(0)
   pin0.write_digital(1)
   pin16.write_digital(0)    

def leftTurn(duration):
   pin8.write_digital(0)
   pin12.write_digital(1)
   sleep(duration)
   
def stopIt():
   pin8.write_digital(1)
   pin12.write_digital(1)
   sleep(2000)

while True:
   startIt()
   
   if button_a.is_pressed():
       leftTurn(100)
   
   if button_b.is_pressed():
       stopIt()



Suggested Resource List
  • Small Electric Motor
  • Kitronik Motor Board
  • Battery Pack
  • BBC Micro:bit
  • Pens
  • Junk (Can or Bottle)
  • Wires
  • Tape
  • Scissors
  • Broken Propeller or un-balanced load
  • Screw Driver


Related Links







All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with.

Wednesday, 17 August 2016

USB Robot arm control with Python and Raspberry Pi

I was asked recently if the USB robot arm could be programmed - I knew the answer was yes. The Arm came from the CBiS Education Robot Arm kit (http://www.cbis.education/Product-Details.aspx?prodid=2 ) which comes with a Raspberry Pi and SD Card with software to control the Arm. So the question has become - How do I program it in Python from scratch?

Well, the honest answer is I don't I use what others have done before. A good 
starting point is this site http://www.wikihow.com/Use-a-USB-Robotic-Arm-with-a-Raspberry-Pi-(Maplin), it gives most (pretty much all) of the answer, including where to get the pyusb library need; setting it up (be careful don't use the  zip file but the tar.gz version  - you might need to scroll down the screen to do this) and an example. A second source that was very useful was  http://notbrainsurgery.livejournal.com/38622.html?view=93150#t93150 which contains an explanation of the 'triples' (for example [32,0,0]) used to select which part of the arm moves and what it does (in the example [32,0,0] causes the Robot Elbow to move down).


The code below is largely based on the code in http://www.wikihow.com/Use-a-USB-Robotic-Arm-with-a-Raspberry-Pi-(Maplin) the only real changes are named procedures (such as ElbowUp) in place of the slightly less easy to understand lines such as  MoveArm(Duration,[4,0,0]) #wrist up . The only other changes was a procedure that changes what the light does (0 - light off; 1 - light on; 3 - pulses by a number of times).

import usb.core, usb.util, time
RoboArm = usb.core.find(idVendor=0x1267, idProduct=0x000)

if RoboArm is None:
    raise ValueError("Arm not found")

Duration=1
#Define a procedure to execute each movement
def MoveArm(Duration, ArmCmd):
    #Start the movement
    RoboArm.ctrl_transfer(0x40,6,0x100,0,ArmCmd,3)
    #Stop the movement after waiting a specified duration
    time.sleep(Duration)
    ArmCmd=[0,0,0]
    RoboArm.ctrl_transfer(0x40,6,0x100,0,ArmCmd,3)

def RotateBaseClockwise(Duration):
    MoveArm(Duration,[0,1,0]) #Rotate base clockwise

def RotateBaseAntiClockwise(Duration):
    MoveArm(Duration,[0,2,0]) #Rotate base clockwise

def ElbowUp(Duration):
    MoveArm(Duration,[16,0,0]) #Elbow up 0x10

def ElbowDown(Duration):
    MoveArm(Duration,[32,0,0]) #Elbow down 0x20

def WristUp(Duration):
    MoveArm(Duration,[4,0,0]) #wrist up 0x04

def WristDown(Duration):
    MoveArm(Duration,[8,0,0]) #wrist down 0x08

def CloseGripper(Duration):
    MoveArm(Duration,[1,0,0]) #close gripper 0x01

def OpenGripper(Duration):
    MoveArm(Duration,[2,0,0]) #open gripper 0x02

def ShoulderUp(Duration):
    MoveArm(Duration,[64,0,0]) #shoulder up 0x40

def ShoulderDown(Duration):
    MoveArm(Duration,[128,0,0]) #shoulder down 0x80

def GripLight(Action, Duration):
    if (Action==1):
        MoveArm(Duration,[0,0,1]) #light on
    if (Action==0):
        MoveArm(Duration,[0,0,0]) #light off
    if (Action==3):
        for x in range(Duration):
            MoveArm(1,[0,0,1]) #light on
            MoveArm(1,[0,0,0]) #light off

WristUp(0.5)
OpenGripper(0.5)
RotateBaseClockwise(2)
RotateBaseAntiClockwise(2)
ElbowUp(1)
ElbowDown(1)
WristDown(0.5)
CloseGripper(0.5)
ShoulderUp(3)
ShoulderDown(1)
GripLight(3,3)


See it action in the video below.








All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with.

Wednesday, 3 August 2016

Traffic lights - Microbit, GlowBugs and micropython

In a previous post, I got a GlowBug to work with a micro:bit (http://robotsandphysicalcomputing.blogspot.co.uk/2016/08/microbit-and-glowbug.html) . In this post, I will show a relatively simple traffic lights system produced by turning off and on the pixels via a micro:bit.




Code
from microbit import *
import neopixel

# Setup the Neopixel strip on pin0 with a length of 3 pixels
np = neopixel.NeoPixel(pin0, 3)

while True:
    #red
    np[0] = (255, 0, 0)
    np[1] = (0,0, 0)
    np[2] = (0,0,0)
    np.show()
    sleep(1000)
    #red and orange
    np[0] = (255, 0, 0)
    np[1] = (255, 69, 0)
    np[2] = (0,0,0)
    np.show()
    sleep(1000)
    #green only
    np[0] = (0, 0, 0)
    np[1] = (0, 0, 0)
    np[2] = (0,255,0)
    np.show()
    sleep(1000)
    #orange
    np[0] = (0, 0, 0)
    np[1] = (255, 69, 0)
    np[2] = (0,0,0)
    np.show()
    sleep(1000)





It is simple, timings and more lights can be added to make a more interesting system. If you have done something similar please use the comments to discuss or link to it.    

Thank you to @SCC_Lancaster for the loan of a micro:bit.


Related Posts
Microbit and GlowBugs
CodeBug and Glowbugs 



All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with.

Monday, 1 August 2016

Micro:bit and Glowbug


I saw on Twitter that some people have got the GlowBugs, more commonly used the CodeBugs (http://www.codebug.org.uk/learn/activity/73/glowbugs/), to work with the Micro:bit. Here is my go at doing it. I just wanted to get one GlowBug to flash Red, Green and Blue and keep cycling around.

The start point was to base it on the code from http://microbit-micropython.readthedocs.io/en/latest/neopixel.html for using Python with neopixels. The GlowBugs are essentially a single neopixel. So I connected the Data In to pin 0 and set the strip length to 1 ( np = neopixel.NeoPixel(pin0, 1) ) and then set the colours by setting np[0] to the colour wanted (eg. Red  np[0] = (255, 0, 0) ).


from microbit import *
import neopixel

# Setup the Neopixel strip on pin0 with a length of 1 pixel
np = neopixel.NeoPixel(pin0, 1)

while True:
    np[0] = (255, 0, 0)
    np.show()
    sleep(1000)
    np[0] = (0, 255, 0)
    np.show()
    sleep(1000)
    np[0] = (0 , 0 , 255)
    np.show()
    sleep(1000)


Video of it in action.




  


All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with.

Gesture controlled python robot unicorn (or is it a rhino)

In the previous two post I built and played with a robot unicorn from  Do it Kits https://doitkits.com/product/robot-unicorn/ . In the first...