Zision Interactive

Had a small get together at my place last weekend, and had the game set up and playable during that time, with a camera on it. I recorded about 12 hours of video, although some of that time it probably wasn't being played... Twice I had the solder break on the flipper wiring to the resistors. I'll need to think of a better way to mount those. Currently they're just hanging awkwardly from the coils from when I first attached them for testing, which obviously is bad. Once the flippers just died randomly, and came back next ball. Not sure if that was a tilt or something correct that the player didn't notice, or if something malfunctioned. Will have to track it down in the recording and see. One time the ramp switch didn't register, which has been a recurring issue. I've got it tweaked 'just right' so it's 99% good, but I need to figure out a better solution eventually. This wouldn't be too big of an issue, except the lock post in the ramp won't let the ball back down, since it doesn't know it's there. I had two other stuck balls, both times they were caught by the shooter lane diverter, pressed against the back of the drop target next to it. Both of these issues will at least be alleviated by a ball search, which I'd never gotten around to coding before. So the next day I added one in. Not too complicated... I shouldn't have put that off so long. Besides from that I had no reported issues, although I'm sure a lot of that was people just not knowing how the game is supposed to work.

Another thing that's been on the todo list for a long time: adjustable GI. When I originally got the led strips, I got some super bright 12V ones since I was worried about how well they'd work. Although the center of the playfield is still a bit dark if you turn off all the other lights in the room, overall it's more playable than some games, but in a lit room they're a bit much. Usually more light would always be better, but they tend to make it harder to see some of the mini displays, especially the ones along the edges. I considered trying to hook them up to a solenoid driver, and manually PWM them to get them to dim, and also give me manual control of them in the code (although I don't really know when I'd use that), but that sounded like it could be a bit of a pain (and who knows if my mosfets can handle that much current), so instead I ordered a cheap 12V LED dimmer off eBay.
It had these annoying bullet plugs that a lot of electronics have, but I've never had a good way to deal with. I was about to go about my usual process of cutting off the plugs, then buzzing out the wires to figure out which is which, and heat shrinking some new wires onto it, when I had a light-bulb moment: what if I just opened it up? Sure enough, two phillips screws on the back were all that was needed to open the case and see four nicely color coded wires soldered to spots on the board
A little bit of soldering, and I now had my own wiring and connectors attached
The dimmer works great, and I now have fine tuned control of the brightness of the GI (and can even turn it off if needed). Still need to find some way to mount this in the cab, but that'll be an issue for later on. At some point before the weather gets too cold I'd like to take the game apart, clean the inside of the cab and put in some final cable management for everything, then sand and stencil the cab with some playing cards.

While I was in the game I also took the opportunity to wire up a few more inserts: 3 in the center of the playfield to show your progress towards a potential wizard mode, and two more in the mini playfield. I stopped using the star rollovers I had installed there to sense the ball a while ago when I made the new diverter, and luckily I was able to find some white inserts that were the same diameter as the star rollovers to replace them with, so now I finally removed the switches and wiring underneath too.

One of the issues I kept running into with the plastic covers was the rollover buttons. My 'free floating' 3d printed ones had ended up working pretty well, but sometimes they'd cause hangups with slow moving balls if the button was also stuck at an angle. In my quest to solve all potential ball trap points, something needed to change. Then someone on the slack channel mentioned these inductive proximity sensors:

Given their side and range, plus the fact that I don't have a wooden playfield in the way, these seemed like a good way to avoid having to deal with sticking the rollovers through the playfield at all. I ordered a few and my initial tests seemed positive. They were easy enough to power from my 12V supply, and just acted like a normal switch once I added a pulldown resistor. The one issue is that I'm using a switch matrix, so I needed some way to interface these 'constant' switches in. I designed yet another little board to go under my playfield which would basically just hook 4 proximity switches into the matrix

I designed some simple 3D printed mounts, and replaced all my rollover buttons
This wasn't quite as well thought out as I'd like, and I had issues fitting them into a few places. I was able to get around that by using some 12mm sensors in a few positions instead of the better range 18mm ones, but the detection of the 12s isn't quite as wide as a star rollover would be. The biggest problem is the rollover in the shooter lane. The 5 bank of drops doesn't leave much room between the rollover and the wall, and the area is just wide enough that the ball can sometimes worm its way past without triggering it. I may have to look into cutting my support rails a bit to make room if this doesn't work out, but I'll see how noticeable it is first. Since I eyeballed the entire cabinet without any planning I've been leaving about 5/8" room on both edges of the bottom of the playfield through the entire length so that nothing could possibly obstruct the support rails, but it could be that this area is far enough forwards that I don't need to worry about it.

Overall these proximity sensors are really cool, and if I'd known about them before I started building my whole playfield might be completely different. I could see myself avoiding rollover lane switches entirely, and maybe some of my hanging gate switches on shots too. The one downside is how tall they are. Compared to the very compact sensors I've seen on the Alien pinball machine, they really obstruct stuff under the playfield, and there's a lot of stuff like mounting them sideways in ball guides and stuff that you could never do. Once I get another shipment of spares in I'm going to chop one open and see if all that size is really needed, or if it's just a big empty cylinder to fit some standard industrial form factor or something...

Having no luck with the flipper resistors, I went to the nuclear option regarding the heat buildup under the playfield, and installed 6 computer fans over all the holes on the cabinet to provide some airflow. Of course, it somehow had zero effect. So, as a last ditch effort, I ordered some PET-G to make a new playfield covering, thinking maybe the acrylic was the issue. To further correct some of the issues with my previous acrylic plastic, I took some rubbings on a large piece of paper and got it scanned at staples.
I'd done similar before with a piece of paper that I'd punched holes in to mark the positions of screws, etc, but some of those were missed or didn't come through well, and I'd also added the holes for all the screens since then, so I needed an update. Based on that, I made an updated CAD file:

Sourcing the PET-G at a reasonable price was a bit of a pain, so I didn't want to waste it. Luckily, I found that I could make serviceable test cuts with my CNC router on plain paper, so I did a few iterations with that to fine tune things. The cuts weren't perfect (rough edges, occasional tears) but it was accurate enough to be useful
Once I was satisfied with all the positioning, I cut the full playfield in PET-G
After reassembling everything again, I did a test game..... and the PET-G buckled just like the acrylic.

So I needed a new approach. Long term the clearest solution here is just to glue everything down, but I don't have any art ready yet and I'm not sure if I could apply and later remove the glue cleanly without damaging the wood. I'd been hoping to eventually cut a new playfield wood with the CNC, but as I continue to have problems with the depth of cut with the PET-G I don't have much confidence in getting that working quickly, so I'm still stuck with my original hand-cut plywood right now.

So I decided to go the other way right now, and instead of attaching everything down even better with glue to prevent the buckling, I decided to just attach as little of it as possible, and make a plastic more like the standard playfield protectors sold for other pins. The new protector would only be held down at three positions (the three posts closest to the center of the playfield), which should keep it from moving, while allowing the plastic to expand/contract as needed to keep from buckling.

Originally I'd rejected this idea when starting to experiment with the plastic covering, as I didn't want the ball to 'sink in' to the empty areas over the screens. But that was also with a thinner material. I'm now using 0.06" plastic, which is much more rigid, and doesn't seem to bend much as it supports a ball over the 9" screen even without being attached down at both sides, so I think it should still play fine.

Now... more test cuts!
Unlike with the full plastic where I only needed to worry about the holes for the screws, here I need to match up to every contour of the ball guides, etc. Which of course I mostly bent by hand/eye and don't have any accurate digital files for. And of course I didn't think to etch them onto the plastic when I got it scanned either. Not a big deal though. I can give even 0.2-0.3" of space around the edges of things safely without affecting the ball (although it looks a bit weird), so I don't need to be super accurate here. And thus, I cut another sheet of PET-G. And also order 2 more spares since I'm now out of stock and I hate to wait for things to ship.

Some things weren't quite as accurate as I thought, but in the end there weren't any major issues. Only two places touched the edges of the plastic, and since it's PET-G it's easy to trim by hand

So now I start reassembling the whole playfield AGAIN to make sure that this still all plays fine. I'm fairly confident this should work though.

For a long time now I've had my start button doubling as an action button (I disabled restarting a game, and then made the start button trigger the action button code snippet once the ball has been plunged), which has been a bit annoying, and hopefully is part of the reason why playtesters keep forgetting I have an action button (doh!). I've also been stealing a lockdown bar from my Whirlwind whenever I do playtesting because... I don't have a lockdown bar for this game!

What I did have though is a really rusty spare lockdown bar sitting around. So I sandblasted it, then following McSquid's advice from his Sonic homebrew, drilled a hole in the bar, painted it black, and successfully mounted a flipper button in it using a 3d printed bracket.

Then I had to get a switch in there!

No problem, just drill two holes in the receiver to mount it, and then squeeze a switch in (with less than 1mm of spare room), snake some wires down, and wire it up. Working good so far, we'll see how it holds up during play

Small updates...

Added a bunch of high scores to the attract mode. Besides stuff like a regular leader board, "best spinner rip", "most hands won", etc I also added a 'lowest scores' board for fun, since technically players can do so bad at poker that they end up in the negative. Could be an interesting thing to compete on!

Had another playtester over for a few hours of gameplay. I noticed they weren't really reading some of the mini screens much. Part of that, I think is just because they're generally really weird. It's hard to get used to looking all over the playfield to see what the writing says. But there's a second issue, which is that some screens were just hard to read. Part of this is due to the viewing angle I think. Displays towards the back of the playfield are both farther away and at a more extreme angle, so they lose contrast. Both of those make them harder to read. But the other thing I realized is that my larger rectangular displays were much dimmer than the smaller square displays I was using for the cards themselves. Each of these displays has a BL pin on them, which is supposedly for the backlight, but I was never able to find much documentation about it, so currently I have it disconnected, and the backlight does seem to work. I wondered if maybe the larger displays needed some extra power on that pin or something, so after failing to find any solid info, I gave up and just started sending random signals in to see what happens. It seems like the BL pin is an active low 'disable' pin to turn it off. Not really useful to me. But while trying to find documentation on it, I also saw some places talking about 3.3V vs 5V. Apparently the actual controller chip on these display boards can run off either voltage, and some manufacturers include level shifting chips so either voltage can be used to communicate. But again, I had no documentation for my boards, which I'd sourced from a random shop on ali express from china in bulk. So I figured, only one way to know for sure!, and just hooked one of the displays up to 5V to see if it smoked or not. Luckily it worked fine, AND got brighter! So I had to rewire all my displays get 5V for power instead of 3V :/

Playtesting also revealed a lot of switch issues. My modified small rollover buttons keep getting stuck in a few places, leading to the game going crazy or balls getting stuck, or sometimes just missing switch hits. I'm hopeful that when I get my CNC fixed and cut a new one, I can align these better, but I'm getting really tired of dealing with issues regarding this. Need to come up with a more permanent solution. I've ordered some proximity sensors to play with, and I also have some other ideas regarding the rollover design to play with.

Around the third hour of playtesting, my new thicker acrylic playfield cover started buckling slightly I'm not sure what causes the heat to do this at this point. I left it for like 8 hours plus with the game on, and had no issues, but now after a few hours I'm having issues? My only other thought at this point is that maybe it's the heat of the flipper coils themselves causing the issue. I've noticed that, especially after long games requiring lots of cradling, the lower flipper coils get quite hot and you can smell them sometimes even, despite the EOS being adjusted properly. I think this is due to the capacitor I've added to the power supply to give them more power. I've ordered some high wattage resistors to attempt to wire in series with the hold winding in a way that they'll reduce the strength of the hold circuit (which is already plenty strong) without affecting the power winding. If that doesn't work, then I may have to mount some tiny fans like people are doing on newer games in order to cool them off.

On the subject of heat, I've also gotten some 120mm computer fans to try to get some airflow moving through the whole cabinet. Even if running the electronics minus the flippers isn't enough to affect the playfield, it still does get quite hot in there and I don't like it. I've also realized that my RPi is mounted upside down on my MPU board, which probably isn't helping things. RPi 4s apparently already run hot, and I had installed some aftermarket heat sinks on mine, but a passive heat sink on the CPU doesn't matter that much if it's upside down. So I've designed a new version of the MPU board which will mount above the RPi to fix that. It should also give me enough space to give the RPi a small dedicated cooling fan if needed.

Pintastic New England has announced their next show will be this November, so bringing the game there is my new goal for the machine. I think it's achievable, in some form, but that means it needs to be able to survive a full day of the public playing it without me being around. At a minimum, I need to fix all these ball hangups. That'll mean fixing some switches, tweaking a few areas of the game slightly, and installing plastics and an apron in case of air balls. I also need to get the action button installed on my lockdown bar to get that presentable. If I can get the game bulletproofed, it'd also be really cool to get some cabinet art, but that might be beyond my capabilities right now. Time will tell...