[maguiar]

Hello All,

In 2015 I built a Halloween dark Ride which took up about half of my driveway and 1/4 of my garage, approximately 300 square feet including 80 feet of track. The name of the dark ride was "The House of Mary". It was a story telling ride that took approximately 5 minutes from beginning to end and included a magic mirror, animated fireplace, animated portraits and tool screen projections from AtmosfearFX.

The purpose of this thread is to share what I did and how I did it. I will be moving through every aspect of the ride covering the track system, the car and the props. Unfortunately, I did not make a lot of videos of the ride in operation as it was a very busy Halloween night. I only made a few the day after during tear down (see below) but I thought that it would give an idea of whats to come.

Please note that I will be providing just the basics using written descriptions, photos and where necessary, videos. There will NOT be a great deal of detail as I feel that the best source of information is going to be the general concepts which are merely opinions of what I think is the best; or not so best method of accomplishing something. Anyone interested in building their own dark ride will more than likely poses the skills necessary to run with whatever info is provided regardless of the source so if detail is what you are looking for, sorry, I just don't have the time to do so.

Also, I can not be held responsible for any damages or wrongdoings that come from using the information that I am about to provide. Use at your own risk!


A video of the car running through the track. This video was originally posted to show how my drive wheels turn so that they remain parallel with the track. This will be covered in later posts.

A video of the car stopping at a scene via the use of a reed switch and magnet, again, something that will be covered in a later post.

 

[maguiar]

Track System

OK, so the bottom of the track is comprised of 4 X 8 sheets of OSB plywood. OSB is a terrible choice as it does not do well with water and warps under the slightest bit of humidity but it was the cheapest option at $8.00 a sheet which makes this perfect in my book.

The straight sections of the rails were made up using 2 - 2" X 2" X 8' or 4' sections of furring strips glued and screwed together creating 1 - 2" X 4" X 8' or 4' section of rail. The reason I used 2 - 2 X 2's is because it helped the rails remain straight as one strip would counter act against the others natural tendency to warp and vice versa.

The curved rail sections are made up of 7 - 3/16" X 2" X 4' sections of plywood glued together. I just cut up a 4' X 4' piece of plywood into 2" X 4' sections, glued both sides of the plywood, mated them together, placed them into a 90° jig (see below) and clamped to dry overnight. The radius of the curved sections is 2' which is best in my opinion as it allows you to remain within the confines of a 4' X 4' section of track. This would allow the track to run immediately parallel to another section of track without having any issues.


Photo of 90° jig.



Photo of raw curved section of rail next to the jig.



A photo of the raw section of track inside the jig.

 

[maguiar]

Track System Continued

After creating the straight and curved rail sections, I let them sit in my garage for a month to see if they would warp and they did not. The next task was to cut off the excess from the ends. To accomplish this, I just placed a curved section on a 4' X 4' section of plywood that had the 2' center marked off with a black sharpie. I then lined up the middle of each curved rail with the 2' marked centers on the plywood, marked the ends and cut off the excess.

Next step was to add sand to the upper half of the rail. I added the sand as my initial tests resulted in the drive wheels slipping on the rail as the plywood was pretty smooth. This was accomplished by adding a strip of painters tape along the midway, running a roller with glue along the length of the rail until it was liberally covered. I then pushed standard plaster sand into the glue using a paintbrush by dabbing into a cup of sand and then dabbing onto the rail. This method worked perfectly, a bit time consuming but the end result was worth it.

Next is to add the aluminum strip to the bottom half of the rail which will act as the power distribution system for the cars needs. I bought a 6" X 25' roll of aluminum flashing. I rolled out a good portion of the flashing on a piece of 2" X 6" plank. I then used a metal 4' ruler and scored the aluminum using a utility knife and then bent the metal along the score lines until it broke, this resulted in a perfectly straight cut. The strips ended up being 2" wide.

The strips of aluminum were attached to the straight and curved sections using standard staples. The strips were cut about 3/4" longer than the ends of the rails and wrapped and stapled around the ends ensuring that each side does not touch. The end of the wrapped sections of aluminum will mate against the next section of rail completing the connection for the transmission of power to the next section of rail.


Completed curved rail section



Upside down



End of curved rail section



Close up of cutout used to connect sections

 

[maguiar]

CAR

The car has the following:

2 - 24 VDC Wheelchair motors. These are used as drive wheels installed on the front of the car because it's easier to pull than push.
1 - 24 VDC PWM. Controls the speed of the car.
4 - 1 1/4" stationary caster wheels. These are used as guides to keep the rear section of the car in line with the track rails, obviously installed in the back.
2 - lawnmower Spindles. Used to allow the drive and guide wheels to rotate freely.
2 - Metal bars that are connected to the guide wheels that act as a power pick-up system.
2 - 4 1/4" full range speakers.
1 - 6" DVC woofer
1 - 12 VDC 500 Watt stereo amplifier.
2 - Arduino UNO. One controls the car and the other controls the sound tracks for the car.
1 - Arduino Sound Shield. Plays the sound tracks.
1 - Relay module. Controlled by the Arduino UNO.
1 - Servo. Controls the POT for the PWM. This is Controlled by the Arduino UNO.
2 - Reed switches. One to detect the cars position on the track and one to detect the state of the cars door (Safety).
1 - RGB LED flexible light strip. Used to light up the interior of the car when it reaches the load/unload station.
3 -Illuminated switches. These are used to program the speed/power of the car, check the status of the car, Safety, and dispatch the car.
4 - 3" swivel caster wheels. These are the wheels that bare the total weight of the car. When you purchase, go with quality over savings as it makes for a smoother ride and helps cut down on friction.


Lets start with the Spindles as this is probably what most people are interested in.

The photos below are of a lawnmower spindle that is used for holding a lawnmowers blade shaft. Not anymore, I think that a better use is to allow some attached drive or guide wheels to turn so that they can remain parallel with a tracks rail system. This eliminates traction and binding problems that are typically seen with a system that has drive and guide wheels attached in a stationary position under the car. Discussions of such problems can be found here.







The photo below shows the cars drive wheels attached to the spindle. Take note of the turn buckles, they can be adjusted over time to help maintain traction. There is a fine line between too much traction and not enough. Too much and you put an additional load on your motors and electrical system, not enough and the wheels slip.



A video of of the cars drive wheels attached to the spindle.

The photo below shows the guide wheels attached to the spindle. A different approach as the spindle is attached to the car whereas the drive wheel spindle pictured above is attached to a piece of sheet metal.

 

[maguiar]

CAR Continued - Drive Wheels


I looked any many different options for the drive wheels and narrowed it down to 2 options, wheelchair motors and industrial gear reduction motors. I chose to go with the wheelchair motors because they were relatively inexpensive and were abundantly available. Most of the industrial gear reduction motors had duty cycles which was not going to work, and when I found one with a duty cycle of 100%, the motor was just too expensive.

The wheelchair motors are 24 VDC, do not have a duty cycle and draw approximately 15 amps under heavy load/startup, and approximately 7 amps while the car is running. These motors have more than enough power to carry 4 adults when used with a track rail system.

There are several different wheelchair/scooter motors available. I chose the motors pictured below because I felt that I was saving a lot of space with the 90° drive train. The only draw back is that you have to raise the bottom of your car to clear the motors but in my opinion, this is not even an issue.

One thing to consider is that the wheels have a softness that I would categorize as medium. Using sand on the tracks rails does provide a great deal of traction but it does eat up these tires quickly. I will be testing other means of providing grip to the wheels to address this but that is for a later date.


Note: The brake cap is removed in these photos.





The drive wheels are installed under the car using a piece of sheet metal that was cut to size to allow the space between the drive wheels to be close to the thickness of the track rails. This piece of sheet metal is then attached to the car using a 5/8" bolt that passes through the lawnmower spindle. The photo's below show this arrangement.

 

[maguiar]

CAR Continued - Guide Wheels

The rear guide wheels were attached using 2 pieces of sheet metal that were bent into a C channel. I used two pieces of sheet metal to help increase the rigidity of the channel while maintaining a bit of give that would spring back. I installed 4 stationary wheels on the left and right sections of the channel which worked perfectly for keeping the car in line with the rails. The photos below show this arrangement.








The guide wheel section also provided a means of hooking up the cars power pick-up system. This was simply 2 bars of metal attached using 2 spring loaded hinges that were isolated with strips of rubber. Additional tension was maintained via a spring installed midway on the bars that was isolated using plastic washers. I used 2 furniture wheels to act as the contact points between the pick-up system and the rails aluminum bus system. These furniture wheels needed to be drilled out and have springs installed behind them to keep enough tension on the ball to ensure that enough contact was maintained to transfer the power. The photos below show this arrangement.

 

[maguiar]

CAR Continued - Power & Control

The car has two sources of power, 24 VDC that it receives through the tracks rail bus system, and 12 VDC that it receives through a battery. The reason for the two sources is because the car is controlled via an Arduino UNO and if the UNO was powered via the bus system, which would loose contact from time to time, every now and then there would be enough of a voltage drop to cause the UNO to reset. To resolve this I first tried using a capacitor but couldn't get the right combination to address the issue effectively so I chose to just put in a 7 AMP Hour battery which has enough power to run the UNO and associated peripherals for more than 20 hours.

The 24 VDC bus system powers the PWM which powers the drive motors, a 24 VDC to 12VDC buck boost transformer which powers the cars lighting and stereo amplifier. The 12 VDC battery powers 2 - Arduino UNO's, 1 - Music Shield, and 1 - 12VDC to 5 VDC transformer that powers a servo used to control the POT on the PWM.

Lets start with the Pulse Width Modulator (PWM). Pictured below is a 24 VDC pulse width modulator that is rated for 30 Amps which can be found on EBAY. The PWM is used to control the speed of the drive motors which is pretty effective from the 10% - 100% range. Anything below 10% does not have enough power to move the car. The power output can be controlled via an on-board potentiometer (POT), via an external 0-5 volts source, or via a 4-20 milliamp source which makes this controller very flexible. I tried to control the PWM using a 5 VDC digital to analog converter (DAC) that was hooked up to the Arduino UNO but the results were not very good as the motors were very jerky. Not having the time to troubleshoot the problem I opted to manually control the PWM's on-board POT via a small servo (pictured below).

Note: The PWM does create some noise and any wires close to it will induce some voltage. The third photo down shows a wire covered in foil. This was needed to address an issue I was having with induced voltage which wreaked havoc on the UNO. Took a while to figure this out, especially without an oscilloscope.

PWM





Servo controlling the PWM

 

[SedgewickHotel]

Wow. I'm sure I speak for just about everyone here when I say that my mind is blown. Thank you for all this information and all the pictures.

All the information you provided makes me think I'm mostly on the right track with my own project. I switched to rubber tires from the nylon ones that came with my wheelchair motors, and that improved by grip problem. I never considered adding texture to the rail. That's creative.

And geez, if you couldn't get the capacitor to work, I know right now to just give up on it. I purchased a "BOSS AUDIO 8 Farad Capacitor" that I thought might work, but I'm thinking I'm in over my head, and will follow your lead with a 7hr 12V battery to power my Arduino.

 

[maguiar]

Wow. I'm sure I speak for just about everyone here when I say that my mind is blown. Thank you for all this information and all the pictures. For some reason, it looks like the pictures aren't showing up in the "Guide Wheels" post. I'd love to see them, though. Not sure if you're able to edit the post, or repost the pictures.

All the information you provided makes me think I'm mostly on the right track with my own project. I switched to rubber tires from the nylon ones that came with my wheelchair motors, and that improved by grip problem. I never considered adding traction to the rail. That's creative.

And geez, if you couldn't get the capacitor to work, I know right now to just give up on it. I purchased a "BOSS AUDIO 8 Farad Capacitor" that I thought might work, but I'm thinking I'm in over my head, and will follow your lead with a 7hr 12V battery to power my Arduino.

Thanks for the compliment. I have been following your progress for the Hauntington Hotel and am excited to see what you come up with. The car looks really good and being one that grew up during the 70/80's, I can appreciate what this ride will mean to those that are familiar.

My original plan for "The House of Mary" was to do a Ghostbusters themed ride that included cars that rotated as well as a laser based gun system that kept score of the ghosts that were shot, similar to the Buzz Lightyear ride at DL. I have some ideas that I can share with you on how to set up a laser based game system. I actually already have the guns and was lucky enough to have found some lasers that had drivers that could modulate up to 40 KHz. Let me know if I should get into this.

I have re-uploaded the guide wheel photos and it looks like everything is OK. In regard to the Capacitor, I did not use a very large capacitor as I was not sure if the charge vs discharge rates would be adequate for meeting the cars needs. What I did was basically a test that did not meet the needs and the cost of the larger capacitors scared me away. I am sure that this could be made to work but my electrical engineering skills are not up to par.

 

[maguiar]

CAR Continued - Power & Control - Arduino

I originally planned on controlling the car via PC by using relays attached to the PC to activate the power to the rails and sensors along the track to tell the PC when to start/stop the car and show scenes. I quickly decided that going wireless would be best as it would eliminate a lot of wiring. I ended up with a flash based touch screen control program that would control the car and all show scenes. This was a hybrid of PC, Arduino and Digi XBee radios. Little did I know that this would almost be the death of me.

The PC flashed based touch screen control program worked perfectly. The system would communicate with the car via radio which allowed me to dispatch from a control panel and actually view where the car was at any point in time. The PC would send commands to the car like start car at 20% power and then await a confirmation response from the car. I could even see if a guest had opened the car door while in the ride.

The biggest problem I had with this set up was maintaining communication. I tried several things to address this from upgrading the radios to the Pro versions to turning off all radios in my house (Access Points, Etc.) with no luck. The main issue was not with starting or stopping the car, it was with the timing required for commands sent to the car to play a certain audio track. If there was a momentary break in communication, it would have a huge impact on the timing for when the car stopped or started and the audio tracks that should be played as part of a show scene. This is not going to work, I need a new plan!

I literally had 2 days left until Halloween and decided to create a stand alone control system based off of the Arduino UNO. So, I wrote a sketch that would check the car for safety issues (Car Door), allow the operator to set the power level of the PWM based upon the occupant load (Child None, Adult None, Child Child, Child Adult, Adult Adult), dispatch the car, stop at show scenes, play audio tracks, turn ON or Off the interior lights of the car when it arrived/departed the loading/unloading zone, and provide feedback via an LCD display. By no means am I a programmer and I had to address a few issue with debounce related to the reed switches but the sketch worked flawlessly. I am going to make the sketch available here just so long as no one gives me the business for what I did wrong because I guarantee that something is wrong! Any help with the sketch would be greatly appreciated.

 

[SedgewickHotel]

My original plan for "The House of Mary" was to do a Ghostbusters themed ride that included cars that rotated as well as a laser based gun system that kept score of the ghosts that were shot, similar to the Buzz Lightyear ride at DL.

I had drawn up plans early on for a rotating car that I'm still very confident in. The reason I abandoned that idea was purely because of space requirements. I hope to be able to resurrect that idea someday, as I tend to think it's completely feasible.

I have some ideas that I can share with you on how to set up a laser based game system. I actually already have the guns and was lucky enough to have found some lasers that had drivers that could modulate up to 40 KHz. Let me know if I should get into this.

I'd love to hear anything you'd be willing to offer. Feel free to post in my thread if you feel like it's too off-topic for this one. I did a ton of research and found some semi-usable tutorials, but I'm starting at square one - I am a total novice at this stuff and everything I do, I'm learning thanks to Google and those who want to share knowledge. I was hoping to use lasers and sensors from this guy, but again, I have no idea (yet) what I'm doing. I've been so focused on my car, I've barely thought about the guns and targets yet. I just recently purchased a vintage carnival game watergun that I want to repurpose as my gun.

 

[Haunted Engineer]

Sedgewick Hotel, I think you and me are on the same brain waves. I also have a rotating version of my cart drawn up and would absolutely love to run it however, the doors leading in and out of my building are too narrow to allow me to do it. Maybe somewhere else next year.

 

[Haunted Engineer]

Using a lawn mower spindle was clever!

 

[Haunted Engineer]

The way you did you electrical pickups was also clever! I wish I could apply this to mine but I would have to take the extra steps in isolating my hot rails from the guide rail since everything is metal. It would be so much easier to control the car.

 

[maguiar]

Using a lawn mower spindle was clever!

The way you did you electrical pickups was also clever! I wish I could apply this to mine but I would have to take the extra steps in isolating my hot rails from the guide rail since everything is metal. It would be so much easier to control the car.

Thanks for the compliments.

What you could do is add a thin sheet of plastic for isolation and then an aluminum strip to the lower end of one side of the rail where the drive and guide wheels do not touch and then use the aluminum strip as your supply and your existing rail as your return. You could use plastic rivets to attach the aluminum and plastic to your rails.

I like your rail system much better as it is much more robust, thin, and is sure to last for many seasons.

 

[SedgewickHotel]

Could you go into a little more detail on the reed switches you used? What kind did you use, what placement did you use, any problems, or things you would have done differently in retrospect? I've been looking at a variety of sensors - motion, distance, magnetic, etc - and would value your opinion on the topic.

 

[maguiar]

Could you go into a little more detail on the reed switches you used? What kind did you use, what placement did you use, any problems, or things you would have done differently in retrospect? I've been looking at a variety of sensors - motion, distance, magnetic, etc - and would value your opinion on the topic.

Sure,

I do not have a make/model number for the magnetic reed switch that I used but they are very common and can be found just about everywhere. I bought mine from a vendor off of EBay because they were really cheap, a bag of 20 for $5.00. They are a normally open, security based reed switch that comes in two parts, a switch with two wires attached, and a matching magnet.

I say security based because that is what they are typically used for. Below is a picture of this switch.


Security Based Reed Switch


This particular switch did work for me and is what the car currently uses although I will be purchasing and testing a hall effect sensor (Image below) as I believe that this would be a better fit as it should cut down on my Arduino UNO sketch length and working time per cycle. Let me explain, with the reed switch, I had to look at the state of the switch over a period of time/cycles and average out the results. Simple but is does have an impact on the UNO's memory because of the array that is generated to calculate the average. This takes microseconds to complete but it is performed every cycle and does have an impact on time.

Adding the code to average out the state of the switch eliminated a huge problem I was having with false positives which were being generated because of vibrations (Movement of the car, the audio system woofer, Etc.) as well as induced voltages (mentioned as a note in post #7). Also, I switched out the magnets that were provided with the reed switches with block magnets I bought at Harbor Freight (Image below). They worked much better because of the increased magnetic field and ease of installation which consisted of hot glue and a firm press.


Hall Effect Sensor - Arduino Compatible


Harbor Freight Block Magnets


The reed switch is installed at the rear of the car. I used a plastic hose (water line for refrigerator) to hang the switch down so that it was approximately 1" from the track. The good thing about the plastic hose is that it is flexible and can take a beating without affecting the position of the switch. So basically, I used the switch and a magnets glued on to the track to tell the car when to stop, speed up or slow down.

This arrangement can be seen at 1:11 of this video.

 

[maguiar]

One thing that I forgot to mention is that I will be testing RFID sensors to see if they are a viable replacement for the reed switch. The code that I wrote to control the car kept track by counting the magnets on the track floor so that if the reed switch passed over 3 magnets, then I knew that I was at scene 3, Etc. As simple as this is, it has a huge flaw and that is if the reed switch does not pick-up a magnet (this happened once last year) it throws the whole ride off and the audio for scene 3 is now playing at scene 4. Not good...

A good solution for this is to use RFID tags along the track instead. If the sensor picks up tag 1 then your at scene 1, if the sensor picks up tag 5 then your at scene 5, Etc. In this case, if your car skips over a scene stop location for whatever reason, your show (from a cars perspective) will still be playing in the correct order.

The RFID sensors and tags are very cheap and there is a lot of code examples available. I also had planned on upgrading the Arduino Uno's to Arduino 101's for extended memory and speed.

 

[maguiar]

Triggering of Scenes & Scene Control

The triggering and control/playing of scenes basically consisted of an Arduino Leonardo, a PC and a relay board connected to the PC.

The car has magnets mounted on the sides that triggered reed switches that were installed on the walls of the of the scene which were hooked up to the Leonardo. The Leonardo was used to trigger the PC via keystrokes (Leonardo is capable of sending key strokes) and is much cheaper than other commercially available triggers, not to mention you can program it to do whatever you want.

Once triggered, I sent a specific key stroke to the PC and used a custom flash based program to control the relay board, sounds and on-screen actions (if I used a TV or projection screen for that particular scene). Why use the PC when you can just use the Leonardo? Well, the PC based flash program is capable of reading multiple sensors at the same time, provides a means of adding video to a scene and does wonders when it comes to timing and sound.

I use Swishmax to program everything and then export is as a stand alone program. Run that program and then it waits for the trigger keystroke and voila, a perfectly synchronized scene that can include multiple music and sound tracks, video if you need it, triggering of external elements such as lighting, smoke machines, bubble machines, air shots, pneumatic's Etc. For those of you that are familiar, this is similar in nature to the Light-O-Rama programming style.

The Leonardo also has two serial ports. This makes it possible to use the Leonardo to send key strokes to the PC and then based upon a specific keystroke provide a return response to the Leonardo over the second serial port for processing of a desired result. This is what I used when I originally planned to control my car via radio and it worked very well, outside of the interment radio communication issues.

 

[maguiar]

Asking for some help with my Magic Mirror enhancements. See Here.

Thanks