Arduino Tutorial 38: Using a Tilt Switch Cut Off With a DC Motor 

Great lesson! Here is the code I ended up having before watching the video: void loop() { bool tiltVal = !digitalRead(tiltPin); digitalWrite(directionPin1, HIGH & tiltVal); digitalWrite(directionPin2, LOW & tiltVal); analogWrite(speedPin, mSpeed); }

I did the homework on the last episode no problem and decided to use the knowledge Ive gained so far afterwards to combine my DC Motor, Servo, and Joystick , X controlling motor speed/direction , Y controlling servo position to point the fan in a desired direction. My longest code so far and was successful right away. Fantastic teaching I can’t thank you enough !

Did the homework! When you see people only viewing for 3 minutes I think you'll find it's people just revisiting sections of tutorials they have watched in entirety previously to help better understand the one they are currently working on. I have certainly done this on multiple occasions!

Completed the homework under 30 minutes on my own. Thanks a lot for your teaching sir

Did the homework. I used a while loop instead and it worked quite nicely. Had to take the delays out like you did. I was yelling at you about the analogWrite instead of the digitalWrite. My wife thinks I'm crazy.

Keep doing these videos. they may not be crazy popular, but you have no idea how much these videos help us.

Did my homeworks, even managed to control speed and direction with a pot and a pushbutton (using the INPUT_PULLUP status given by one of your followers)... I'm so happy that 2 days ago I didn't even know how to use a component... now I just feel like understanding is at hand ! What I like the most is when you explain by physics and math how and why things work in a component. It's so helpfull !

Finished the homework before watching this. I used an else statement instead of another if statement. Thank God for you! God bless you sir!

Hi, Paul. Did the homework on my own successfully. Since the bread board is so big and I hate to have to tear it down and start over most times, I decided to see if I could combine lessons 35, 36, 37 and 38, both schematic and code, so I could run the whole shmear at once. So, now I have a reversible stepper motor driven by a toggle switch, a DC motor and fan running clockwise (so the air blows out/up from the blades), and both motors stop if the tilt switch goes to 1... with green and red LEDs to indicate when it is normal vs "tilted". I'm sure the battery doesn't love running 2 motors at once, but the PS does seem to handle it. My board is quite full, but I didn't run out of pins! Fun!

I did my homework and had it working prior to watching this episode. Setting the motor speed to zero seemed logical, so that's what I did. The only mod I made was to put the tilt-switch on a couple of male/female wire extensions to make the tip-over testing easier. Thank you for another wonderful lesson. 👍

Made it through the homework unscathed. Love the homework assignments!

I made it Mr. McWhoter. Great video as always. I will finish this course to the end. So far I haven't had any problem and I've managed to pull out every assignment before see in you doing it. I always watch your videos up until the last second. Thank for your hard work doing these videos.

Hi Paul, I incorporated the tilts witch and again used the pinMode(tiltPin, INPUT_PULLUP) ; as this reduces the code by a line(one less to get wrong). I found that like yours in the video there was a delay between the tilt switch activating and the fan stopping so I played around with the delay times and took the kick play down to 50mS and the delay after the analogWrite(speedPin,mSpeed); line down to 100mS and this gave a nice snappy response and I was also able to get it to start back up when righted at an initial speed of 75. I wish I hadn't torn down the joystick board now ( I have 2 UNO boards) still its all part of the lesson. Off I go to the homework bench. Great job as usual.

I completed the homework prior to watching this lesson. The logic was pretty straight forward. I used an If-Else statement to solve the logic. It worked great with very little issues. Thanks for the knowledge.

Hi Paul. Did my homework and very close to your solution. I also pointed out your baud rate error in my comments to Tutorial 37. Really enjoying these tutorials. Thanks

My coding was slightly different initially, but still got it to work. Yours was definitely more streamlined. On to my next homework assignment.

Did it on my own, sir. Thank you for all the lessons. 38 down. 20 more to goooooo!!!

This one was cake!! The only thing to this point that I’m struggling to conceptualize is the toggle switch. It gets easier the more I practice with it tho

love these. I used a nested if loop to give the motor the "kickstart" so I could initiate spinning at a lower RPM.

Did homework, but, simply put the tilt switch in series with Vcc. Thanks for another great lesson.

I am now able to add the tilt cut off with flashing red LED. Control the speed of the motor with a potentiometer. Turn the whole thing off and on and reset the tilt state with a button. I just wanted to take the time before finishing this video to let thank you for this series! You taught me how to do Fusion 360 and I'm so happy to continue to be able to learn from you. Reply

I did this after the previous lesson all on my own! Loving the videos! int speedPin=5; int dir1=4; int dir2=3; int tiltPin=2; int tiltVal=0; int mSpeed=255; void setup() { // put your setup code here, to run once: pinMode(speedPin,OUTPUT); pinMode(dir1,OUTPUT); pinMode(dir2,OUTPUT); pinMode(tiltPin,INPUT); digitalWrite(tiltPin,HIGH); pinMode(buttonPin,INPUT); Serial.begin(9600); } void loop() { // put your main code here, to run repeatedly: tiltVal=digitalRead(tiltPin); analogWrite(speedPin,mSpeed); Serial.println(tiltVal); if(tiltVal==1){ digitalWrite(dir1,LOW); digitalWrite(dir2,LOW); analogWrite(speedPin,mSpeed); tiltVal=digitalRead(tiltPin); Serial.println(tiltVal); } if(tiltVal==0){ digitalWrite(dir1,HIGH); digitalWrite(dir2,LOW); analogWrite(speedPin,mSpeed); tiltVal=digitalRead(tiltPin); Serial.println(tiltVal); } }

Paul Still only watching the complete videos. My goal is learning to READ arduino code. Future plan is to then return to the very first lesson and repeat each one in succession actually' doing the activity. I do have the kit now and I am getting familiar with it as I watch. Normal mode is to watch to near the end and stop the video, depending on time available hold in that state or go to the next one. Thank You, this is the first set of videos that I have stayed with.

I did what you did except I inverted the read from the tilt switch so that when it was in the OK position I was reading "1" from the tilt switch, that way I could simply multiply the motor speed variable by the result of the tilt switch read and if the device is OK the motor would run and if the device were "tilted" the result "0" multiplied by the speed variable would, of course, result in "0" effectively shutting off the motor. I like to avoid using conditional statements when I can as it slows down program execution. Also I was a bit confused when you gave the assignment as to if you were expecting us to use the tilt switch and hard wire it to electrically break the circuit or use it as a sensor and use program control to shut it down. I opted for the later as I figured it was mostly a coding exercise. Thanks again. I'm learning a lot.

I did the homework with flawless victory! Can't wait to start on the joystick controls!

Thank you Paul! I am happy to have you here!

BOOOOOM!!! Did it all by myself, coded it a slightly different way. Tilt sensor wasn't working at first, narrowed it down to hardware issue through your excellent de-bugging training; moved it away from the columns occupied by L293D and giddy up!!!! Success!

I did it myself. I also added a potentiometer to control the speed and a button to change direction. Off to do the joystick assignment now.

I did it ;) (it was kind of easy) Thanks so much for all these AMAZING TUTORIALS!! These homework assignments are so important I am so glad you do them!!

I used the tilt switch and also used the photo detector,. they work great together. The motor does slow down with low light and full speed at full light. Thank you Paul always a good day to watch your lessons.

I was thinking about where a tilt switch is used and there is one in my portable heater that shuts it off to prevent fires. It also turns on a red light. Really useful information 👍

As I tell my students, any homework I give you, I do myself. I did the homework because the only way to really learn is to try things on your own. Doing this is really helpful because a day will come when there is no one to guide you but yourself. Thanks for another great video.

Still there watching all the way through to the very end Paul, as always a very interesting tutorial, thanks again!!

Did the homework and got it working just fine. This one was easy.

I did the HW before watching , and it was working, thanks to your great explanations about tilt function earlier! Thanks again, you are the perfect teacher.

The tilt switch homework was easy and ill be getting to work on the joystick HW in the morning as it is getting late. Thanks you Paul!

Hey Paul, I sure did the home work plus I added the green and red LED to show a visual warning if the fan tipped over.

I'm definitely doing my homework. And I do watch all the way to the end of every episode .

My version was about 90% the same as your version including pin and variable names. I lean toward the if/else versus the if/if approach. Good lesson, getting more comfortable with the thought process for the design. Keep it up, thanks.

Great teacher ! I have been watching your videos since a week and now I have reached this lesson. Wish you a great day for you and you granddaughter.

Assignment is completed! Love your lessons and started to learn math because of your inspiration! Thank you very much.

Homework done and now on to the next one! Thank you for the great lessons!

I did my homework. I only added one if statement in my code, so that when tiltVal == 1, the command digitalWrite(speedPin, LOW) was executed. Thanks for the great lesson Paul!

I got it before to watch the video, basically it was easy applying the concepts I learnt in the 2 previous videos . I am looking forward to doing the next homework with the joystick.

Hi Paul, I did the homework and got it to work. I wrote the same code as you created, but added two extra variables : mSpeedStart=250 & mSpeedStop=0 then I used these variables in the if statements, although mine worked, I wrote more unnecessary code. Thanks again Paul

Mr McWhortor, I just received the elegoo super starter kit today. I should have gotten that a long time ago. I had a problem getting the board going but checked the com channel and it was different than my Arduino. I changed that and, it is working fine and ran the sketches that I uploaded to it. I'm good to go and now I have the sensors to follow your videos. Thanks for the advice. That starter kit is absolutely the way to go.

Tried it hands on and was successful in completing my homework :) Thankyou so much!!!

Completed homework on my own. Looking forward to the next tutorial. Thanks Paul!

Of course i've done my homework. Always do! I even tried to go further including a joystick on my own but i'll have to wait for the next lecture to figure it out.

Did the homework between lessons. Got it working, after watching you code it, I had to look over my shoulder to see if you had watched me write the code, almost identical right down to variable names. 😀

I'm watching your videos up until the last second. Thank you so much for your work!

Hi Paul, I looked the lesson until the end :-) ...and I made my homework! I appreciate your effort for teaching us very much! Thank you a lot!!!

I did this for homework last lesson, but used if else. It worked for a while but then I started getting both one and zero tiltVal readings when it was tipped. Realized I needed to fake a pulldown resister using digitalWrite high. Then it worked consistently.

Watched to the end, and your coding was almost exactly like mine! Thank you! Off to do more homework!

Brilliant!! I managed the tilt and stop homework on my own. The next project looks tricky though. Thanks.

Was able to do this, simple enough and added a active buzzer as part of the tilt.

Did the homework successfully before this lesson. Did it two ways. 1/ like you did with the simple "if" on the tilt switch and 2/ with the state change as in lesson 29.

I did the homework without a problem. Thanks once again Paul.

Done and dusted. Added two motors due to the use of L298N board. Great tutorial yet again.

Boom, done already on my own from homework assignment. you are an excellent teacher. thanks so much.

I absolutely love these lessons. Lets have a "Yippy i yay" for Paul

Yes did the homework and worked great. I like the fact you make mistakes (whether deliberate or not) as this makes us analyse the issue.

could do the HW from last episode no problem... I wanted to add more functions but my batteries die to fast , I ordered a lithium battery hopping this can help me get more creative. I added a Servo and a joystick , I could control the speed and direction with the joystick . very long code , I still cant believe it worked !!! thank you Mrs Paul.

Using this to control an rc crawler thank you! Back to the servo and IR control lessons. Glad I did my homework and mapped my buttons.

I've completed the homework and look forward to comparing your solution, to be shown in lesson 39.This was a fun assignment. On another note, I did not buy my Elegoo kit at the beginning of this series, so I have a lot of earlier lessons to do. One of those, lesson 22 (active buzzer), has homework to add a potentiometer to sound the buzzer when the potentiometer has a value greater than or equal to 1000. I decided to do this one. Since my breadboard is currently set up for lesson 38, the Arduino 5V pin is in use by the joystick. The potentiometer needs 5V, GND, and an Arduino analog pin. Rather than use the Arduino 5V pin, I thought that, since the power board that is already on my breadboard outputs 5V, I would use that with the potentiometer. Much to my surprise, when turning the potentiometer from low to high, the value went from 0 to around 995. Adding code as shown in lesson 12 (potentiometer) to also show voltage, the 995 value corresponds to 4.86V, a little shy of 5V. I am using an AC-DC adapter to power the power board. I did verify that the AC-DC adapter is outputting 9.03V, so it appears to me that my power board is not outputting 5V. Just to doublecheck, I did hook up the potentiometer directly to the Arduino 5V pin. In that case, the maximum potentiometer value (and voltage) is 1023 (and 5.00V), as expected. Could someone here check if their power boards behave similarly? The simplest test is to repeat lesson 12 (potentiometer), but hook it to 5V and GND on the lesson 38 breadboard layout so that it is powered by the power board. This is not a problem, just a surprise. The DC motor and stepper motor lessons work fine, even if the power board outputs slightly less than 5V.

I did the assignment after few corrections it work OK. After I put the decimal point everything work fine. Thanks again.

Super challenging homework, but mostly was able to do it. Thanks for your great instruction!

This was a fun easy project. I set mine up very similar to yours except mine worked correctly the first time because I did a digitalRead(tiltPin) instead of analogRead(tiltPin) like you did. The other difference I had was instead of using analogWrite(speed_pin,0); I created and used another variable - motorOff=0 to shut off the motor using analogWrite(speed_pin,motorOff); Once again, thank you for a fine lesson!

Yes, Sir, I did the homework! It was nice and straightforward to incorporate the idea for the tilt switch from Tutorial #36 with the code from #37 to control the on/off of the DC motor. I think I must be learning something here! 8-) The only differences I have were to use if ... else instead of two ifs., and my pinMode is (tiltPin,INPUT_PULLUP), as per a suggestion in a comment in an earlier video.

I did the homework basically the same as you. The only difference I also put the motor directions in my if statements, which I realize now was unnecessary.

I did my homework before watching the video worked great. Todays homework is going to be fun really like how you assign homework to test your viewers learning progression though these series of videos.

Yes sir.....I am able to do the homework....I am eagerly waiting for the next Tuesday at 9:30 pm in India....Thank you.

Enjoyed, and yes I did do the Homework, not quite the same way you did, but still with success.

I put the tilt resistor in series with the fan power. Works great and doesn't require any change to the code. I know it's not in the spirit of the homework, but it's basically a 0ohm switch.

Not having much luck with some of the Elegoo components. I revisited lesson 37 because I ended up taking 5v directly from the Uno to pin 8 on the mtr controller to make the motor work. The power supply board is only giving 2.6v. Now the motor is making some background noise and won't start at 90rpm. I have to start at about 150. This is my 4th bad component. They did replace the Pot and the joystick but now I have either a bad power supply or mtr controller and a bad motor. Thankfully this stuff is very cheap to buy. I like that you are putting the code and diagrams on you TTB site. Cool modded tinkercad like diagram.

Great tutorial as usual. Did the math already for the joystick and all works fine. I really love to do the homework in front, and then see how you did it afterwars. Start getting the hang on the math stuff 🤓. Can't thank you enough for taking the time and effort to explain all those things to us ✌

watching start to finish and doing the homework. Fun and helpful series.

Yes I always do the homework and watch to the end :-) Great stuff incorporating earlier learned stuff.

Keyword Rose and Ronald Another great lesson, I am planning to use a DC motor to drive my observatory dome using mirror tiles fitted every 10 degrees around the dome and for position control with infrared photo sensors. I have learnt a great deal so far

yup, did homework and solved it......you are an excellent teacher, giddyup...

did the homework, love that I just know how to do it. It's all thanks to you, my good sir.

I complete the home work. Worked great. Did it the same as you. Thanks for these videos.

Easy - once I remembered to do the resistor trick on the tiltPin. :) I am very much enjoying this series.

Yes, I did the homework and got it working before this episode. Used, basically, the same approach as in this episode.

Yup. Did the hw and now going to do this one with the joystick. I'm so close to phase 3 which is to use all this and build a robot. I still love how you teach btw.

Yep, did the HWrk, and used 2 x If's (not an 'else') , Like you advised before... but used 'digitalRead' not 'analogRead' off pin 2. worked a treat ...

Rose amd Ronald! I always watch all videos to the end and more than once!.

Successfully completed the homework. Only difference is that I had the if statements only redefine the motor speed, then I still had the digitalWrite and analogWrite commands after.

Yes I did the homework in Lesson 37, but used the tilt sw to drive both IN1 and IN2 HIGH, to stop the motor.

Hi Paul, nice work as usual. I learn a lot from your videos. I do the homework and have had some success. Have that I keep getting distracted coming up with silly projects of my own by combining different lessons. Thanks for your help

OK You got me back and I renewed my $10 a month. You taught me Fusion 360 and i am designing and 3D Printing train parts for my 1950s American Flyer. Now i need a new motor contoller and came here to learn Arduino. Hoping the Nano or ESP32 could work with the 1950s Motor and AC track power. I have 3 Uno's 1 Nano and now 1 Pi running my Octoprint, boy is that nice. Take care thanks for the training. As a Patreon do we get to ask questions, Specific to our projects? All the best, Dennis and yes Rose & I forgot

I did do the assignment and was successful. My code was like yours for the most part. One small difference.

Love the videos! We appreciate you. I did this one a bit different, but your way seemed to work better.

That was brilliant, many thanks. My motor is OK, I had it plugged into the VIN not 5v. Aging eyes. Still a problem with either the power supply board or the controller but there is a work around.

Did my tilt switch homework, pretty much the same except I used an “if else” command. Off to do my joystick homework now, looking forward to this, bit more challenging than the tilt switch 👍👍

Did the homework on my own👌. My code was a bit different but it worked the same! Used and if, else statement 👍🏻.

Yes,I did the assignment myself, but make a mistake , finally figured it out in this video

I was able to do the homework before watching you do it. I did it the same way you did it.

Boom, would you look at that. Learning all things arduino with you is fun. Yes doin the home work, was delighted when the tilt I did in less lines. I did tiltPin,INPUT_PULLUP then one if (digitalRead tiltPin==HIGH){analogWrite (speedPin,0);} noooo don’t put numbers in the void. Thank you from Ireland for all your hard work and expertise.

Very very educating to me and my friends, really dragged us into the µC buissness. Thanks to Paul !