Ball on plate, Balancing

Mechatronica project, Ht4 E2a-2 HAN Arnhem.

Category:

Science & Technology

Tags:

• Ball
• plate
• balance
• ht4
• bal
• plaat
• pid
• labview
• webcam
• mechatronica

[lasolita222]

Hi,

very nice job. I am trying to do something similar in the spare time by my self. Unfortunately, I am not able to find proper ball joints. Can you give me some information about them. Which model have you used? Do you know a web site where I can buy them?

Thanks.

[ehelmink]

@lasolita222 Hi!

That's nice! In spare time, wow! Haha..

We toke the ball joints from wall fixations which is made for hanging a television on the wall.. You'll have to be lucky to find it..

Sorry i can't help you..

I wish you a lot of success and maybe i'll see your yourtube video soon?!

[krimoc]

Mr ehelmink, I would like to see the physics describing the interaction between the center knee joint and the two knee joints that are connected to the servos. Will you please reveal those derivations? Thank you, once again for your assistance.

[ehelmink]

@krimoc Dear Krimoc.. Thanks for contacting again! We did everything by white- and blackbox modeling.. I can sent you these (global) information? I think its project specific.. How is it going with your project?? Nice to see someone else his project..!! Haha.. ;)

[krimoc]

Nice job gentlemen! I'm trying to do a similar project for a controls class and I'd like to know where I can purchase the central pivot and servo pivot assemblies that attach to the underside of the plate. Thank you in advance for all your help.

[ehelmink]

@krimoc Thanks!

Nice job to do the same project. We've got the pivot's from a knee-bearing. We've cut off the threaded sides and used glue on the tops for the metal plates which are glued on the surfrace plate. For the bearings we used additional oil-flued.

Success with your project!

[iRouRoui]

This looks like too much mathematics to do

[parkchaehyong]

Mr. ehelmink,

Nice job Mr. ehelmink.

I am doing a similar project for final year project. May I know where to get the universal joint?

[rodstartube]

hello, how do you monitor the ball, with a camera, or what??

[tranducthien1987]

it operates very well. I want to make one like this. Now i have just began , could you talk me what steps do i have to do. Thanks

[ehelmink]

@noveel1 The specifications doesn't matter... You can buy a regular servo motor.. I bigger and stronger can be better, but needs more current, you have to keep that in mind for your electronics.. Bigger servo's can also be slower, due to their input/output ratio (gearbox)

[noveel1]

Plaese tell me the specifications of the motor thier torque and speed.. also the name of company

[ehelmink]

@kmowez Yes, we used servo motors. We made an analog signal to pulses. For control we used the NI-6008. This device gives output signals in volts. This is not useable for servo motors. With a microcontroller we make a pulsesignal. The pulse is connected to a power amplifier for a higher current for the servo's. I have the documents, but its all in Dutch..

[kmowez]

@ehelmink you used servo motors for the plate control right?I was a bit confused about how you utilized output from the pid control to control the motors as in did you change it to pulses?

[ehelmink]

@kmowez Labview collect data from a standard logitech webcam. Labview makes greyscale view of the image and you will see the white ball on its black background. Labview calculates the position of the ball and the position the user wants. This is all controlled with a PID regulator.

The code is very big, many *.VI files...

[kmowez]

Hey you used labview for this system right?

Can you upload the code pls

[ehelmink]

@demollyon Yes, we are students of a university in the Netherlands. Thanks!

[demollyon]

this is pretty cool! are guys students in a university or something?

[zubairhussain123]

where can i find the rod joint you use for the middle of the platform?

[gan3ram4scientist]

wow... tats wonderful...

i was askin about the picture dimensions in pixels..

[ehelmink]

It was hard to get, but nice to do! ;-) Our delay time is arround the 0,2 sec. We used a simple webcam with 30 fps (in black and white). By dimensions you mean the plate? This was 30*30 cm.. :-)

Thanks! :-)

[gan3ram4scientist]

Good wrk !!! i can understand the diffiulties you must hav had with lighting and ur mechanical design ! i hav a small clarificaton.. starting from the capture of a picture frame ,to the values to servo control circuitry how much tym ur image processing consumes ???? and ur frame dimensions wer?

[ehelmink]

its possible.. But you can't see when the car is corning when you use inside a real car.. ;-) On a RC car it would be nice to see!