Maker Pro
Maker Pro

IR Sensor

slicedbread1

Oct 18, 2015
2
Joined
Oct 18, 2015
Messages
2
Hi, I have a project as attached.
I was just wondering if someone could explain what Component 9 - "Sharp IR Sensor plug and wire assembly." plays in this project?

Thanks!
 

Attachments

  • Project.pdf
    58.6 KB · Views: 71

GPG

Sep 18, 2015
452
Joined
Sep 18, 2015
Messages
452
Seems to be for detecting the position of the pendulum.
 

davenn

Moderator
Sep 5, 2009
14,042
Joined
Sep 5, 2009
Messages
14,042
if that is the only info you have been given ... it sux and is woefully inadequate

talk to whoever is getting you to do this project
 

biggerB

Oct 4, 2015
6
Joined
Oct 4, 2015
Messages
6
I've worked with the linked sensor before (https://www.sparkfun.com/products/12728), it is a very simple IR distance sensor, which outputs a gradient analog voltage depending on the distance of the surface from which the IR is reflected.. Like GPG said, it seems to be for detecting the angle / position of the pendulum.

I guess you could mount it on the side of the pendulum such that it points to the mass at the end of the pendulum and constantly read the distances necessary. Its pretty scrappy since the pendulum mass isn't always gonna be in front of the sensor (or maybe it will be, who knows).

Ask your professor (or whoever gave you the project) about using the sensor. I would personally use a low friction rotary potentiometer or even a rotary encoder to detect the angle (theta) of the pendulum, but I'm not certain if it would work well with labview since I've not used it much.
 

hevans1944

Hop - AC8NS
Jun 21, 2012
4,739
Joined
Jun 21, 2012
Messages
4,739
So, are you going to mount your inverted pendulum on a motor-driven wheeled cart and then move the cart back and forth to keep the center-of-gravity of the pendulum over the bottom pivot point? This is a classic closed-loop control design problem. Some insight can be found here.
 

hevans1944

Hop - AC8NS
Jun 21, 2012
4,739
Joined
Jun 21, 2012
Messages
4,739
.

Damn . . . . this could only have been more impressive . . . . if using a 10 ft pole. ...
Hard to imagine a more impressive undergraduate school project. And the young man nailed it, both theoretically as well as practically. I hadn't thought of re-purposing a printer to serve as the carriage under the inverted pendulum.

Of course almost anyone can balance a broom handle of an upside down broom in the palm of their hand. It just takes a little "eye-hand" coordination and perhaps some practice to train "muscle memory" to the task. It would be velllly interesting to see a two-axis cart rigged with a control system that can do the same thing.

The two-dimensional inverted pendulum problem has to be similar to the problem of how to keep rocket engines aimed in the right direction to apply reactive thrust through the center of gravity of the space vehicle. I have always been impressed by the smoothness with which space launches execute the roll maneuver to position vehicles for orbital insertion. Well, actually, it is roll, pitch and yaw simultaneously but let's keep it "simple" for now. I don't know how it is done, but surely it involves moving the rocket engines which are mounted on gimbals. Hmmm. Two degrees of freedom for control but three degrees of freedom for response...no wonder space exploration is risky business. But you have to start somewhere.
 

wingnut

Aug 9, 2012
259
Joined
Aug 9, 2012
Messages
259
I would love someone to try the following....

Take a radio-controlled car and glue its controller on top of the car. Now extend the joystick of the controller by 3'.
And viola! It might balance that extended joystick as in the above demonstration. If the joystick fell forward, the car would move forward to balance it again. If the extended joystick fell backwards, the car would move backwards and balance that again.
 

wingnut

Aug 9, 2012
259
Joined
Aug 9, 2012
Messages
259
Inspired by the above video, and for what it's worth, here is a link to my Youtube video where I attempt to balance a stick on top of a radio-controlled car.
 

AnalogKid

Jun 10, 2015
2,665
Joined
Jun 10, 2015
Messages
2,665
Sidney Darlington, famous for his two-transistor precursor to the entire concept of integrated circuits, had other marketable skills. He was awarded the Presidential Medal of Freedom for inventing radio controlled missile guidance, working out the control equations referred to in post #8. They still are in use today. Like the sign over my office door says, sometimes it really is rocket science.

ak
 

davenn

Moderator
Sep 5, 2009
14,042
Joined
Sep 5, 2009
Messages
14,042
would love someone to try the following....

Take a radio-controlled car and glue its controller on top of the car. Now extend the joystick of the controller by 3'.
And viola! It might balance that extended joystick as in the above demonstration. If the joystick fell forward, the car would move forward to balance it again. If the extended joystick fell backwards, the car would move backwards and balance that again.

obviously you haven't seen a Segway either ;)

just 2 wheels .... Adam from Mythbusters is often zooming around on his one

2590834103_7d3736f826_z.jpg


Darth Vader even has one .....

16624-fast_segway_teaser.jpg


Dave
 

M-Bagheri

Nov 13, 2015
2
Joined
Nov 13, 2015
Messages
2
Hello
Probably a typical motion sensor for motion detection pendulum will suffice.
The sensor is able to do

Some of it is presented at the address below.
elmha
 
Top