Recently I was playing around with an augmented reality robot on my mobile phone https://developer.apple.com/augmented-reality/quick-look/ (it doesn’t do much on a desktop computer). After a while of course you get fed up with virtual stuff and I thought that it would be more fun to make a tangible desktop robot with parts that really move.
I wanted something friendly that wasn’t too complicated and something which initially looks like nothing special but which you can discover by pushing bits to see what happens. Best would be something to make you smile as things start to move. A sort of stringless desktop puppet, which reminded me that I always wanted to have a go at a pinocchio puppet with an extensible nose for when it starts telling lies. The hands should be useful but, for simplicity’s sake, should not have too many fingers so a spanner shape seemed just right. To make the nose extend, I made Blubot’s top tilt around its centre line, and a rod attached to the back of the top yields enough of a push to make the nose stick out. I even did a simple drawing to check that it would move far enough.
Drawing to check the clearance for the eyes and the movement of the nose
This is basically a 10 x 10 x 8 cm box. The parts are cut from 10 mm plywood with a saw or a scroll saw for the curved bits. Good quality plywood means that the individual layers are properly glued and cutting doesn’t cause too much splintering.
Parts for the box
The nose is a piece of 12 mm diameter dowel in a 13 mm hole. It was then handy to use a piece of the same 12 mm dowel to fix the nose linkage to the hinged lid. The linkage is a piece of 1.6 mm brass rod.
Top part of the box with eyes and nose
The nose linkage
I painted the eyes before gluing them in place and I glued a row of small hemispheres along both sides to make a sort of rivety impression.
Initial version of Blubot
Addition to the design
At this point I painted all of it and tried it out on my four-year old test pilot. More or less her first comment was that it has no legs. I had originally thought that legs wouldn’t add much to the narrative and might destabilise things. On reflection, I thought, OK well let’s add something moveable to the legs and decided on child-safe rocket flames, which come out on lift off. They just dangle on the string and disappear when you place the model on a flat surface, sliding back up into the legs.
Making the legs and feet
For the feet, I used MDF, drilled a hole for the flame, used a bowsaw to cut a round shape and then sanded a taper. Continuing the rivet theme, I added 4 hemispheres to each foot which then look like toes, elephant’s toes!
The flame (right) slides out of the leg (left) and is retained by the string
I thus added three chunky legs, each with a hole drilled through the centre to accommodate the flames, each made of a piece of suitably shaped and painted dowel. Add a piece of string to prevent the flames from completely falling out and Bob’s your uncle!
It was good to work with better quality plywood than I sometimes do and I was very pleased with my simple wooden hinge at the back of the box. I generally find working with brass hinges quite hard work in such small items. Also, tilting the lid with two fingers to reveal the eyes and extend the nose gives you a very good level of control. Just right for puppeteering!
I find that the longer something takes, the more ideas that you have, don’t you? Even when you are painting, things can occur to you and it was only while painting that I thought of rivets for the eyebrows. 3D rivets were no good, as the lid wouldn’t close so I opted for nice painted red dots instead, which are the very first things to appear as you start tilting the lid. Almost the last things to appear are the two goofy teeth which is quite a funny climax to the opening of the box. I had originally planned on a full set of teeth, changing my mind at the last instant.
The flaming legs were quite simply an afterthought. It’s hard to imagine everything in your head right at the beginning. As things come together in reality, it is then easier to think a bit further and to grow your original idea.
Link for images https://www.wordwise.de/Blubot_images.zip
Link for leg images https://www.wordwise.de/Blubot_new_images.zip