No comments
Fun, lessons, The Challenges

Somewhere Over the Rainbow – Colour Detection

One of this years challenges is to detect  some coloured balls from a distance and visit them.

The full details are here. http://piwars.org/2018-competition/challenges/somewhere-over-the-rainbow/

For our robot we are using a Raspberry Pi Camera and OpenCV to detect the colours and some code written in C++.

You can see a video of our robot doing some colour detection below.

Whilst testing this we have come unstuck with the detection when it is dark or when somebody (Vince) in a very red coat walks into the frame of the camera and it detects him and not the ball.

We are planning on using a 2 times lens to bring the balls into a better focus.

Read More
No comments
lessons, models

Modelling lessons

Keith has been using Fusion360 for a while now, in fact, he first used it back in 2015 to design the second Ipswich Makerspace PiWars robot as shown below.

Piwars 2015 entry render PiWars 2015 entry render

 

 

 

 

Along the way Keith has learned many lessons, some lessons have been fundamental, as an example the model the renders above were taken from are so broken that they are now unusable.  Towards the end of production for this robot in 2015, Keith was struggling so much with the model that the physical robot only existing one week prior to the competition.  These days Keith is far more competent with Fusion360, but he is still learning lessons.

Recently for the PiWars 4 (2018) competition Keith was designing a mount for a Nerf gun, which included a servo for the trigger mechanism.  Because Servos are common on robots, Keith created a servo model which he could then insert into many different models, or the same model many times.  This is what the model looks like.

Servo without wiresOnce inserted into the main model it looks like this, lovely isn’t it.

So lovely in fact, that Keith printed it, it came out very nice. What do you think?

3D printed servo mountWith much enthusiasm Keith went to mount the servo, here is where he hit the problem, and it is a problem he has had in the past, so he really should have known better.  This is the problem.

Oops, servos have wiresYes, you’ve got it, there is no opening for the wires.  Having done this one too many times now, Keith decided to do something about it.  He updated is master servo model to include the wires and this is what it looks like now.

Servo with wiresSo no more will Keith forget to create openings for the servo wires.  The mount has now been updated and is waiting to be printed.

Modified servo mount

Read More