Start to finish of the physical build.

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About Bobbie

Bobbie is the 3rd spider in my plan of building 7 robot models, each robot is based around specific success criteria. Bobbie has some basic success criteria:

With all this in mind, Bobbie doesn’t need to move fast or carry any heavy weights, he’s just a functional spider that is smart. …

Cause who doesn’t want to do that?

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Waveshare GameHAT

Ever since Steve — the first robot in the robotic spider army — I’m known to make robotic spiders. I learn by making mistakes or just simply finding things I can’t do and figuring it out, like when I figured out that Yorick (spider #2) was way too heavy.

I need to be able to drive my robots and the latest robot (at the time of writing) is Bobbie and I don’t really have a controller.

It’s all about Control

Bobbie, the 3rd instalment in the spider army and I need to be able to drive him by giving him simple instructions. …

Assembling and adapting as we go

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In part 1 I outlined why/what/how I was going to build a 3d printer. I’ve been working on it slowly for many months but I have finally got to phase 2, codenamed “just make the damn thing go ffs”.

The extruder and hot end

I had planned on using a dual bowden head on the Chimera but when I realised that the logic board only had 5 stepper controllers (MKS 1.4) this made me think long and hard about it and I came to the conclusion that I have no need for dual-headed printing… so there’s no point doing it.

It became obvious that the main point of this new printer was to move plastic like no-one’s business, so I scrapped the dual Chimera head and went for an E3D volcano hot end running a 0.6mm …

Aim for the moon!

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Yorick v6

“Shoot for the moon. Even if you miss, you’ll land among the stars.” — Norman Vincent Peale.

I’ve got a plan to build an army of robotic spiders. By army I mean more robots than I can directly control at once …and not all of them will be spiders, I have some scratchings of praying mantis and even a wasp.

How to un-heavy a robot and getting it moving

Yorick is the 2nd instalment of my robotic spider army (post explaining that to come!). I’ve been working on Yorick for 4 and a bit years. The kick-off story is here and the follow up to v8.0 is here.

It’s all about the size

Yorick V 8.0 is about 10kg and has a 1.2m leg span, he’s a monstrous robot. The size and weight creates implications that lead to time and cost blow-outs.

Why does size and weight cause time/cost blow outs? One word; Torque. I’ve gone into a bit of detail in the past about this but I’ll repeat it here anyways.

A force that tends to cause rotation. …

The big robot has more stuff going on

As I mentioned here in 2016, I’m building a large spider robot called Yorick. At the time of writing I was up to version 4. He’s had a bunch of iterations since then, I’ve been slack/busy and neglected writing a blog about it. But here’s the catch-up.

Yorick is now (as of writing this) at Version 8. I thought I’d get the story up to date, cause I’ve got some more updates to come soon.

Why so many iterations?

Because I am making this up as I go along and I’m using major mistakes as my course of learning. I tend to call a bunch of work a version when I replace more than half of the hardware or when there’s a significant milestone. …

As a crazy robot guy, it’s important to me to be exposed to lot’s of things I don’t know. For this reason I buy cool tech things like the xpider and the geio ar battle robots and I often go to events and talk to people about tech.

Recently a place that’s close to my heart, Scienceworks did their annual Robotica event.

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Robotica is a small-ish event that’s offered as part of the price of museum entry which is free for many and very reasonably priced for everyone else. …

Getting the plan down

I’ve been 3d printing for a few years now, it started in January 2015 with me at a public library, playing with their 3d printer.

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I had 6 weeks off between jobs… Anyone who knows me will understand that 6 weeks of free time usually leads to me going completely insane or making something a little different. It was the time I decided that I would build robots.

Since then I’ve being going up to 11 with 3d printing and modelling. I’ve spoken about it publicly, I’ve taken a bunch of printers to a conference and taught people how to make and print stuff, I’ve purchased 8 printers and even given away a couple printers. …

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For SLA printing and other stuff

An SLA printer makes liquid turn to solid by using light — that in itself is pretty awesome to me.

I got a Gizmo GiziPro while ago and its awesome! The GiziPro uses a projector to expose and entire layer at once, it’s very quick and astoundingly accurate. However, once a part is printed it still needs a bit more UV to develop the material completely. Also, sometimes I need to “weld” parts together or or fill gaps by hand.

The first tool I need is a UV curing box to completely develop the resin, this will require a bunch of construction and I am lazy and tired so I am going to start with a UV wand. …

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TLDR at the bottom!

As per a previous post, I want to make smarter robots and it occurs to me that it would be awesome to apply some developer tricks to make it better.

My favourite developer trick (after multi-line editing) is to employ a fast-fail/quick-run approach whereby the project runtime environment can be quickly spun up and the changes you make can be seen immediately, good stuff goes and bad stuff breaks straight away.

With this approach I can quickly iterate changes as I go. Also I’d like to use machine learning to improve the robots. …


Adam Purdie

I just love to make stuff and share a good story about it — so here are some of my personal stories.

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