I love all the welding you have done on your Trek theme machine! https://pinside.com/pinball/forum/topic/star-trek-discovery-pinball-machine-/page/8

Next time I weld wireforms I’m going to try to milling copper plates to snuggle up next to the weld junctions. I’ll put one on each side of the weld as you do. That should help limit spill over heat and damage to the rod.

Greek Gods burnt out another servo. The ramp diverter flap managed to pinch a ball when changing directions from left to right ramp. It wasn’t supposed to happen since the trigger for the ball switch is lower on the playfield. But it did. A jammed servo struggles against the impossible load and gives up the magic smoke. Time to rethink the diverter.

8FFA54B4-48E0-4D9D-8F76-BB6513F1CEEB (resized).jpeg

The problem with a standard servo is that it does not know when to give up. It receives a pulse frequency from the PDLED which it faithfully converts to an angle. If it does not reach the angle it tries harder. Eventually heat is the end of its control circuit or motor. At this point my options are to make my servo smarter or switch to a stepper. If a stepper does not reach its goal it does not give a crap. It executes its 800 micro steps (or whatever) to achieve the desired angle and give a shrug as if to say “I did what you said. 800 steps were conducted.” The worst that happens with a stepper is that it gets out of alignment until told to find its home position with feedback from a micro switch. You might wonder about using coils on the diverter. I’d have to put them under the playfield, right through the middle of a subway. So smarter servo or stepper it is.

Looking at the geometry, a servo sure fits better in that place. The shaft of a stepper is in the middle of the motor whereas a servo is offset. While a stepper is probably a more reliable solution, to use it, I would have to either mount the motor above the flap or use a transmission to move the axle.Both possible but a more significant redesign. Instead I think I’ll try to make a smarter servo.

Thank you Jan for the excellent video on servos. I remember us talking online about the disable making its way into MPF. I didn’t notice that it was already there.On my current configuration, the servo is taking the beating of the ball. I’m relying on the metal gearing to hold together. Im realizing that was a mistake. I need to add stops on the ramp for the flap so the servo can bring the flap just shy of the stop and then disable, letting friction hold it in position and the stop to take the beating.

On an early version Are used 12v mini coils just blow the ramp flap. It mostly worked but mechanically was not as reliable as the stepper I replaced it with. The steppe went away when I re-designed the orbit for lack of space. Real coils would be a more robust solution but there is not quite enough room for me too put a coil and the requisite transmission to control that flap. I believe I have worked out a way to detect ball jams. Rather than put a switch on each flap position, I will try putting one in the middle. When a ball gets pinched, the flap can’t make its full excursion and I should be able to detect a prolonged “middle” switch activation and reverse the servo.

A mechanical switch and cam is turning out not to be as reliable as what I expect to get out of this Opto interrupter. I bought a few of these thinking I could use them on spinners but the gap wasn’t quite wide enough to make it work. Lucky for me I kept them and it should be perfect for this.

5D6FA0FA-EE46-4BCB-9FA6-A4D049DB450E (resized).jpeg

Here’s a list of all the things I’m doing to mitigate a marginal diverter flap design:
1: Put a fuse on the servo. My reading says that the servo should draw about 300 mA when moving and draws about 2 A when jammed. I’m putting a 1A fuse on the power line. 2: my replacement servo is a digital servo that allows me to program a power reduction when jammed. So far the drivers have failed to load properly under windows 10. If I can get this figured out I will program a step down in power when jammed to be a backup to the fuse. 3. After stops are welded in, l’ll deactivate the servo after the flap position is reached or a timer has expired. 4. Use the middle position optical gap switch (above) to detect movement of the diverter flap. If the switch stays active more than 500 ms, reverse the direction and try again. 5. Make the servo easier to swap out so if it fails at a show I will be able to do a 30 minute repair/calibration to have the machine running again.

I am wired up and the switch is working. Now for a little calibration and testing.

03E04D36-5EE8-4406-B868-97F9362507A8 (resized).jpeg

That’s a good idea. The servo would still be working against the spring but not with nearly the force of it grinding against a steel ball. Maybe I could mill something out of aluminum to hold the spring(s). It would be an interesting fix. Thank you.

Update on the ball pinching flap diverter: For now I am sticking with the above redesign. I had to rewrite my servo control routines using a state machine in MPF. In addition to logic that’s a lot easier to follow, I also have mitigation steps that detect when the servo has triggered and didn’t make the full arc. Now a jam causes the servo to reverse and try again. It works in both test and real play so I’m going to stick with it even though it’s an imperfect solution. If it would not require a significant redesign I would either use a servo plus spring mechanism or drive the diverter with a stepper motor which would be undamaged by a jam.

Greek Gods is heading to Pinball Expo (Chicago Oct 28-30). I had some friends over to test play the home brew. No crashes or stuck balls. They did find some minor modifications for me to make to the font and rules. I have been worried that the game is either too hard or too easy but it seems to be right on the mark for a skilled player. Overall it looks like it’s going to play great.

An important thing I learned in play testing is that the prompts given by the call-outs, playfield and backbox screens aren’t nearly as effective in teaching a new player how to run the game as I thought they would be. (This is always a big problem when learning a new pinball machine.) To hopefully solve this, I’m creating a slide kit for the attract mode. Pressing the flipper buttons activates the kit and pages through a subset of slides devoted to the rules of the game identifying the strategy and important shots.

Those are good tips. Thank you. I will clear my audits before the show starts so I can keep some statistics. It might be fun to throw those numbers up on the attract mode. If I get ambitious I might turn it into a plot versus time. That would be a cool slide to have.

I'm working up my instruction slide deck for the attract mode. When not playing, hitting the knee switch causes attract mode to stop playing the attract display loop and instead starts showing a tutorial of the game. The tutorial shows on the back box monitor. I'll try to finish the ten or so slides over the weekend before I have more people over to test the machine in advance of bring it to Expo in Chicago. Comments and suggestions welcome. Here is the first slide.

instructions_intro-01 (resized).png

Argh! I misspelled Sisyphus. Correcting.... I really should have my daughter reading these slides first.

Slide 2.

instructions_prmb (resized).png

Slide 3.

instructions_knee_switch (resized).png

I'm putting an extra switch on order in case somebody gets mad and tries to rack my big blue button.

Slide 4.

instructions_ormb (resized).png

Slide 5.

instructions_power_ball-01 (resized).png

Slide 6.

instructions_mystery (resized).png

Slide 7.

instructions_outlanes (resized).png

Slide 8.

instructions_goddess (resized).png

Slide 9.

instructions_super_spinner-01 (resized).png

Those are just the ones worth highlighting!

Bingopodcast Found some typos. Fixing them now. Thank you!.

Slide10.

instructions_hydra (resized).png

Here is a slide I'm adding to the attract mode. The QR code takes the people back here to pinside.

attract_insides (resized).png

Yes I do. Thank you. Our friend Nick of Bingo Podcast noticed that too. Correcting. I should have put the number of line of python code in the machine folder. Zero! It proves how complex a game can be made just with the framework. In the last version of the game I had about 100 lines of python you helped me with to make a custom rule for accelerating balls past optos. If there is time I will fold this back into the code for Expo in ten days.

I'm adding in this P3-ROC slide to my attract mode to give Multimorphic its due. I pulled the P3 logo from some corner of the net. Adding ROC as 3D text should have taken 3 min in photoshop but dragged out about an hour because photoshop 22 is broken and Adobe has discontinued 3D support! This was a nice feature for extruding a layer into a 3D object and adding a light effects and shadow. I dug around for an explanation and Adobe is saying the change is because the 3D back ends have changed with updated hardware and (my interpretation) its too much work to rewrite it. 3D support has been in photoshop for about 8 years now and was a major feature of the platform distinguishing it from free options. While I've felt that Adobe has been falling behind for many years this is the most glaring example I've seen to date. Regarding the ROC, eventually I just plopped down the text and added an appropriately angled shadow. Imperfect but passable.

p3roc (resized).png

I need some quality vector art for the 4K back box screen. With expo a little over a week away, I am buying some art rather than having my artist render it a fresh. The best art I’m seeing is on adobe stock. Licensing it however is very confusing. But I finally fInally figured it out. You can’t buy images or vector art for $10 each any more. It’s only by subscription. The default subscription is $30 a month with ten images monthly and unused credits cary over. 1 month free trial. Here is the catch: if you don’t cancel within 30 days the $30 a month is charged x 12 and you can’t exit the contract for a year! After a year it’s month by month. Or you can get the cancel any time contract for 30 a month but only 3 assets are granted a month. I needed 4 assets and went with the monthly plan. Now that I am subscribed, I picked up the fourth asset for a one time charge of $10 which I feel is fair given the quality. By the way, the artist get 1/3 of the proceeds. After I wrap up this phase, I plan to cancel the subscription, hopefully without any sludge from Adobe.

Pinball Expo countdown: 3 days. Here in Kansas City I’ve been deep in the programming putting the finishing touches on Greek Gods. The few who have played it previously will notice a new score screen, refined messages to the player, cleaned up light shows and a rich sound track honoring the earlier work of Danny Elfman. Along the way I managed to swat some difficult to find corner-case bugs. Fingers crossed more don’t show up on final testing tomorrow.

All the music is installed and I’m not finding bugs when testing. Tomorrow I’m taking of the back box, legs, removing the monitor, and the mini playfield. In the evening I’ll be loading it into the SUV for an 8 hour drive to Expo.

8 hours of driving in the driving rain and Greek Gods has arrived in Schaumburg Illinois for Pinball Expo. Inspection found the MOBO’s graphic card dislodged but it reseated and after reattaching the back box and reconnecting about a dozen plugs it fired fight up. Only one optical switch was out of alignment. Everything is running great. Jack Danger broke it in with the first game!

Seeing scores of people play Greek Gods is a lot of fun. In the process, the more skillful players are uncovering some minor logic problems that I didn’t know existed. One of the core features of the game is that if you score high enough, you get to redeem your soul in the underworld and get a fourth ball on the main playfield. The error I am seeing is that if you already earned an extra ball the logic sends the player to the underworld before the extra ball is used up. This morning I set up for some last minute coding. Half way through, an air handler started raining on the home brews. I am not to be deterred.

882C9FE2-8A01-469D-A6D9-782A9579CD66 (resized).jpeg