Sunday, June 12, 2022

The Black Knight Rises - June 2022 Progress Update

A lot has happened since the last full project update.  The Black Knight Rises playfield build is completed, the electronics are all working, the cabinet switches were wired up, the playfield finally left the rotisserie and lives in the cabinet, and gameplay debug and multi-media development are under way.

The Black Knight Rises has risen!

When time has allowed, over the past 8 months I have troubleshot some build issues, swapped out some mechanical assemblies and switches, refined controller firmware, and did a ton of code development.

Except for a few small items, the physical build is essentially complete.  The main task that remains for me to complete is the actual game multi-media elements like sound effects, videos cut scenes, DMD animations, plus some enhanced game rules.

Click through for the full update.  There were a lot of lessons learned.

The Challenges of 3D Printed Pinball Parts

Life for parts inside a pinball machine is rough.  Literally.  Anything that comes into contact with a speeding ball of steel is in for some abuse.  Look at some of the metal components that have been in service for decades, and they will often be deformed or broken.  And even more destructive are the super powerful solenoids.

This makes life incredibly tough for 3D printed plastic pinball parts.  Is survival even an option?

Most of the 3D printed parts I've designed do not come under any direct stress.  Things like electrical connection mounting brackets, or decorative toys.

For example, here is a 3D printed Monty Python Black Knight toy on top of the upper playfield's shooter lane ball ramp.  I was finding that balls would bounce and get caught on the metal hood.  A 3D printed flat-topped cover solved that problem, and provided a perfect place to mount a toy.

A 3D printed cover (black) prevents balls from getting stuck, and made a perfect spot to mount a toy

But one of the 3D printed parts I designed for The Black Knight Rises are some drop  targets, to make an Alvin G drop target assembly cosmetically match the Williams drop target style.

Designing a drop target doppelgänger was easy.  Coming up with a design that would survive has been the real challenge.

My original prints were in ABS.  They broke.

I also tried PLA, which broke even faster.

I upgraded to PETG, which lasted longer, but also broke.

I modified the design to be more massive, in hopes of making it more robust.  And that broke even faster.

Original Alvin G drop target in white.  ABS red and PETG black design revisions all broke.

Surprisingly, the target head itself never broke, even though it takes direct hits from the pinballs.

Click through to learn the rest of the story.

Chameleon Power Driver v5 - It Works!

 This update should have been posted last October, but I got sidetracked.  Better late than never, eh?

My PCB order from JLCPCB arrived on October 1st, and luckily all boards looked perfect.  For this order, I had the PCB's panelized, so I could assemble them on my Pick'n'Place machine in batches of six.

The Chameleon Power Driver v5 PCB's waiting for assembly

I made a pretty cool video showing the PCB assembly and validation process - it's a surprising amount of work:  Chameleon Power Driver v5 Assembly




At the end of the video you can see a brief glimpse of my new testing jig.  I custom designed and 3D printed this jig to test each power driver.  There are spring loaded POGO pins inside that make contact with various test points on the PCB.  

Click through for the rest of the details.

Progress Update & Troubleshooting Power Driver Issues

I originally wrote this update back in September 2021, but I got sidetracked and it never got posted.  I'm posting it now, as a precursor to the follow-up posts that are coming soon.


Chameleon Pinball Engine Software Updates

Chameleon Pinball Engine software updates were more extensive than I expected, as I was in the middle of a massive rewrite 4 years ago when I took a break from the project.  It has taken a lot of effort to figure out what changes still had to be made.

This has actual been a source of disappointment for me.  In my head, I was remembering being much further along in my coding.  I had certainly brainstormed a lot of features, and even begun coding a few of them, but upon code examination I'm finding little of it complete.

A lot of the missing functionality has been in the playfield configuration section, which means I have to write new code to handle all the new features I've been planning for years.

The good news is that I've improved my coding skills over the past five years, and I'm a much better programmer than when I started the Chameleon Pinball Engine all those years ago.  The new features are coming along quite easily.


Another Chameleon Power Driver Flaw

Four years ago, in my runup to the 2017 Southern-Fried Gaming Expo, I was testing my Chameleon Power Driver v4.0 with a Magna-save electro-magnet, and it was working fantastically... until it wasn't.  I thought my new design was immune to Transient Voltage Spikes (TVS), as if somehow the laws of physics ceased to apply to my design.  Physics proved me wrong, and the power driver was easily fried when hundreds of volts rushed in from the collapsing magnetic field.

Click through for the rest of the story.