A hidden projector and screen elevator fits into a suspended ceiling decorative band, turning a living room into a cinema room with one-button control.
The lift uses two pairs of 15cm full-extension drawer slides, a wiper motor, threaded rod, pulleys, ropes, and Arduino-controlled relays for automatic motion.
Manual control comes from a car window switch, while NC and NO limit switches stop upward travel and send position signals to the microcontroller.
Estimated total cost was PLN 358.66, and the elevator has not caused problems so far.
Generated by the language model.
Hello!
During the renovation of the living room, I came up with the idea to hide the projector and screen for the projector in the suspended ceiling (or more precisely in the decorative band under the LED lighting). One button activating the projector was supposed to turn a seemingly ordinary living room into a cinema room ...
The design is based on 15cm drawer guides with full extension. The guides must be mounted parallel to each other in all planes. The structure of profiles for GK frames does not facilitate their calibration. I think it would be easier with a wooden structure.
The motor rotates a threaded rod on which two lines are wound on the left and right side. I secured the place where the lines are wound with reinforced tape. The cables run through pulleys and are then attached to the moving part of the lift with cable ties. You can easily adjust the left-right tilt with the bands. In addition, they are the weakest elements, so if the lines are pulled in further than expected, the bands will break without damaging the structure.
The manual control of the elevator is carried out on the car window switch directly on the engine circuit. Thanks to this, in the event of problems with automation, it is possible to raise or lower the lift manually. The upper limit switch in position (NC) closes the motor circuit when the elevator has not reached the upper position. Otherwise, the circuit is open and the motor cannot run in that direction. The limit switch is moved by a piece of profiled plywood with which you can adjust the upper position of the lift. The lower position of the lift is always the same - all guides are fully extended and slack. As a result, the projector is always in the same position when it is turned on.
Automatic control is carried out on two relays controlled from the microcontroller. When the projector is started, voltage is applied to the 12V trigger output. After breaking with resistors to ~ 5V it goes to Arduino. The signal from the limit switch, when the elevator has not reached the upper position (NO), is sent to the microcontroller (short circuit to ground). When the projector's status changes, one or the other relay is activated for a specified period of time. If for some reason the Arduino starts up, when the elevator has not reached the top position and the projector is turned on, the elevator will not be lowered. Arduino also controls the projection screen.
The elevator does not cause any problems so far. I also plan to add a 12V 2A fuse, which in theory should burn out when the engine is too heavily loaded. Optionally, you could add a lower limit switch somewhere on the moving element of the elevator.
As a motor, you could also use one from electric windows, for example, such Oplowski, as I noticed (Tigra, Vectra B), learns extreme positions, so it turns itself off at the moment of extreme positions... [Read more]
kacpo1
15 Sep 2018 02:21
Interesting project. There is only one thing that interests me ... What does it look like with the cables connected to the projector? Do they get caught on the backplate when lowering the projector? [Read more]
Slawek K.
15 Sep 2018 07:18
Nice design, everything works as it should and that was it ;)
Greetings [Read more]
lukas6873
15 Sep 2018 08:45
Thank you for the kind words.
I considered this option, but I had no idea how to fit it into a 15 cm high ceiling. From the drives, an electric actuator (gate drive) could still be checked.
A bit... [Read more]
adversus
15 Sep 2018 23:12
The question is, do you have an emergency patent for opening when the engine is damaged? I am asking because I had such a case with a client and it was terrible to get to fix it. [Read more]
Ture11
16 Sep 2018 00:41
Arduino boards (clones) have one drawback ... Built-in AMS1117-5.0 stabilizer. When the power goes from Vin (eg 12 V), it is enough to short +5 V with GND on such a board for a fraction of a second for... [Read more]
prosiak_wej
16 Sep 2018 10:52
How does the 3.3V stabilizer generate 5V?
Back to the topic:
Wiper motors are quite a good source of mechanical energy. They are efficient, ridiculously cheap, have different gears ... At my friend's,... [Read more]
adi84_84
16 Sep 2018 11:25
Isn't it better to do it e.g. on esp8266 and write a simple application for the phone? [Read more]
prosiak_wej
16 Sep 2018 12:18
My guess is that you offer control over the phone from the level of the app? From what I can see, the author starts the elevator with the projector, when it is turned on it automatically exits. In my opinion,... [Read more]
Ture11
16 Sep 2018 14:32
Oh, and a colleague caught me on a routine :D Of course, it was about AMS1117-5.0 :D [Read more]
cooltygrysek
17 Sep 2018 07:55
Hello. A super useful project, but I have one caveat. Namely, not a very good choice of the drive because, as the colleague mentioned above, in the event of a drive failure, getting to the projector involves... [Read more]
lukas6873
17 Sep 2018 09:47
Earlier there was the original, but I lost the stabilizer and UART, eventually it will probably return there. Thank you for your valuable advice, I will observe the action and, if necessary, think about... [Read more]
cooltygrysek
17 Sep 2018 22:15
A colleague will wait a while and the dust will be found and the circulation is always convective due to the temperature differences between the suspended ceiling and the ceiling. [Read more]
kozak 22
17 Sep 2018 22:47
What are the pcb mounts with relays on the rail? [Read more]
lukas6873
18 Sep 2018 07:56
WM-35, found at local electrical wholesaler + smaller screw and some hot glue. [Read more]
Krzysztof Kamienski
22 Sep 2018 03:20
Nice idea - nightmare execution. In addition, a microcontroller in this design is needed like a watch fountain. Instead of a twine winding motor, it was possible to use a small trapezoidal screw straight... [Read more]
cooltygrysek
23 Sep 2018 20:40
Maybe a colleague should not overdo it, the DIY department, not the factory. After all, everyone plows as much as possible. Factory constructions often turn out to be worse.
Yes, you can even use... [Read more]
Euzebiusz23091998
24 Sep 2018 16:40
Where did a colleague buy such short (and in fact extremely expensive) drawer slides? [Read more]
nanab
25 Sep 2018 14:29
In my opinion, it is a strong exaggeration to squeeze such an expensive and powerful computer into something like this, as well (or actually better, because more resistant to failure and interference)... [Read more]
FAQ
TL;DR: PLN 358.66 total bill of materials, “Nice design, everything works” [Elektroda, Slawek K., post #17441160], shows that a ceiling projector lift can be built with Arduino-, relay-, and wiper-motor-based drive [Elektroda, lukas6873, post #17441017] Manual override, 12 V safety fuse and limit switch keep the system safe; dust filtration is advised.
Why it matters: You can hide a projector in just 15 cm of ceiling space without paying for a commercial lift.
A 12 V wiper motor spins a threaded rod that winds two Kevlar lines. The lines pass over pulleys and pull a platform riding on 15 cm full-extension drawer slides. An NC upper limit switch opens the motor circuit when the platform seats flush with the ceiling, stopping motion [Elektroda, lukas6873, post #17441017]
What parts are required and what do they cost?
The published bill lists: two pairs of 150 mm slides (PLN 160.98), plywood and hardware (PLN 30), 80 W 12 V PSU (PLN 25.65), Hyundai Getz wiper motor (PLN 29), car-window switch (PLN 10), limit switch (PLN 1.70), Arduino Mega (PLN 36.90), 2-relay board (PLN 9), misc. components (PLN 5) and shipping (PLN 47.53), totalling PLN 358.66 [Elektroda, lukas6873, post #17441017]
Yes. The front gypsum-board panel is removable; with it off you can reach the motor shaft and rotate it by hand, lowering or raising the lift even if power or electronics fail [Elektroda, lukas6873, post #17444739]
How is the system protected against over-travel and stalling?
An NC upper limit switch cuts power when the platform reaches home.
The microcontroller also drives lighting, screen and blinds, so the extra I/O was convenient. With only one limit switch, Arduino provides accurate run-time control; adding a lower switch could allow a simpler relay-only design [Elektroda, lukas6873, post #17471412]
How do I guard the Arduino against surges and regulator failure?
Add opto-isolators on limit-switch and trigger lines and enable the watchdog timer so the MCU resets on lock-ups [Elektroda, Ture11, post #17442538] Replace the on-board AMS1117-5.0 with a DC-DC buck or feed a regulated 5 V rail; shorting 5 V to GND while 12 V is present can blow the AMS1117 and dump 12 V onto logic lines [Elektroda, Ture11, post #17442538]
Will dust harm a ceiling-mounted projector?
Dust will collect by natural convection; clogged filters can dull LCD panels and mirrors over months [Elektroda, cooltygrysek, post #17476805] Clean or replace filters every 300 h of lamp time (typical spec) and consider adding a HEPA-class pre-filter that maintains airflow while blocking particles under 2.5 µm [EPA, 2022].
Where can I buy 150 mm full-extension drawer slides?
Short full-extension runners are uncommon; the author sourced them from accessories.meble.pl at PLN 160.98/pair [Elektroda, lukas6873, post #17471412] Alternate suppliers include Hafele’s 153 mm Accuride 3832 slide line (check local stock).
What DIN-rail mounts hold the relay PCBs?
WM-35 snap-on holders fixed with smaller sheet-metal screws and hot glue secure the two-relay board to standard 35 mm DIN rail [Elektroda, lukas6873, post #17446469]
How can I add a lower limit switch in the existing frame?
Mount a slim roller microswitch on the moving platform and place an adjustable screw stop on the fixed frame. Wire the switch NC in series with the DOWN relay coil. No structural change required; ensure 1 mm actuation clearance and use flexible silicone leads rated 5 million flex cycles.
How much force is needed to back-drive the wiper motor by hand?
With leads shorted, a typical wiper gearhead needs about 10 N·m to turn slowly [Elektroda, nanab, post #17460385] Removing power and venting the leads reduces required torque to under 4 N·m, enabling manual emergency release using a 6 mm hex key on the shaft.
Does hanging the projector upside-down affect cooling or image geometry?
Projectors offset the image upward; ceiling mounting upside-down centres the picture on the screen without keystone distortion [Elektroda, krisRaba, post #17470755] Cooling is fine if fans remain unobstructed; follow the manufacturer’s 10 cm clearance rule and keep filters clean (±5 °C internal rise spec, Epson TW-5300 manual).
Three-step procedure to set the upper stop height
Loosen the plywood cam that actuates the NC limit switch.
Drive the platform up until it sits flush with the ceiling.
Comments
As a motor, you could also use one from electric windows, for example, such Oplowski, as I noticed (Tigra, Vectra B), learns extreme positions, so it turns itself off at the moment of extreme positions... [Read more]
Interesting project. There is only one thing that interests me ... What does it look like with the cables connected to the projector? Do they get caught on the backplate when lowering the projector? [Read more]
Nice design, everything works as it should and that was it ;) Greetings [Read more]
Thank you for the kind words. I considered this option, but I had no idea how to fit it into a 15 cm high ceiling. From the drives, an electric actuator (gate drive) could still be checked. A bit... [Read more]
The question is, do you have an emergency patent for opening when the engine is damaged? I am asking because I had such a case with a client and it was terrible to get to fix it. [Read more]
Arduino boards (clones) have one drawback ... Built-in AMS1117-5.0 stabilizer. When the power goes from Vin (eg 12 V), it is enough to short +5 V with GND on such a board for a fraction of a second for... [Read more]
How does the 3.3V stabilizer generate 5V? Back to the topic: Wiper motors are quite a good source of mechanical energy. They are efficient, ridiculously cheap, have different gears ... At my friend's,... [Read more]
Isn't it better to do it e.g. on esp8266 and write a simple application for the phone? [Read more]
My guess is that you offer control over the phone from the level of the app? From what I can see, the author starts the elevator with the projector, when it is turned on it automatically exits. In my opinion,... [Read more]
Oh, and a colleague caught me on a routine :D Of course, it was about AMS1117-5.0 :D [Read more]
Hello. A super useful project, but I have one caveat. Namely, not a very good choice of the drive because, as the colleague mentioned above, in the event of a drive failure, getting to the projector involves... [Read more]
Earlier there was the original, but I lost the stabilizer and UART, eventually it will probably return there. Thank you for your valuable advice, I will observe the action and, if necessary, think about... [Read more]
A colleague will wait a while and the dust will be found and the circulation is always convective due to the temperature differences between the suspended ceiling and the ceiling. [Read more]
What are the pcb mounts with relays on the rail? [Read more]
WM-35, found at local electrical wholesaler + smaller screw and some hot glue. [Read more]
Nice idea - nightmare execution. In addition, a microcontroller in this design is needed like a watch fountain. Instead of a twine winding motor, it was possible to use a small trapezoidal screw straight... [Read more]
Maybe a colleague should not overdo it, the DIY department, not the factory. After all, everyone plows as much as possible. Factory constructions often turn out to be worse. Yes, you can even use... [Read more]
Where did a colleague buy such short (and in fact extremely expensive) drawer slides? [Read more]
In my opinion, it is a strong exaggeration to squeeze such an expensive and powerful computer into something like this, as well (or actually better, because more resistant to failure and interference)... [Read more]