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?
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.
@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.. ;)
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.
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.
@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)
@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.
@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?
@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..
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?
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.. :-)
I think its possible.. We tried to build it on a RC car, but there are some problems.. The system requires a power source and a laptop.. Maybe you can build it? ;-)
Oh i know.. i takes 3 months to built the segway.. the difficult thing was to implement the pid on the arm 7 , because floating point is not supported in the NXT Toolkit.. Maybe i will you the NXT Motors for turning the plate.. i will just let you know when the project is ready.. so tot ziens
okay... i know it, but the usb driver is not officily supported by NI... anyway i like your applikation ...especially the demo mode is very cool ... Did you use the PID Toolkit ??? I have used it for my NXT Segway as you can see in my Videos ..
Maybe your demo would be a great show for a booth ... i would try to make this with the arm 7 Board and LabVIEW Embedded.. are there new plans for further demos....???
Yes i know.. Somebody of NI told me.. But its nice to work with! We used the PID toolkit. All this work is done in 7-8 weeks, so a lot of work, the find how things work etc. It this moment we have no further plans, cause our subject is finished/closed..
I saw some cool stuff on your youtube site! Asspecially the segway and its gyrosensor!
The possition of the ball is measured by a standard webcam (logitech quickcam pro 4000). The video from the sensor in the cam is used with labview (national instruments), this app measures the possition in pixels (by contrast (black/white))
Aah okay, nice! Whe used vision tools for usb cause we had an usb cam.. We really liked it. But to (auto)set the preferences is difficult. You see a pop-up for the settings everytime the program is started.
This looks like too much mathematics to do
iRouRoui 1 month ago
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?
parkchaehyong 1 month ago
hello, how do you monitor the ball, with a camera, or what??
rodstartube 4 months ago
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
tranducthien1987 4 months ago
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.
lasolita222 10 months ago
@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?!
ehelmink 10 months ago
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.
krimoc 1 year ago
@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.. ;)
ehelmink 1 year ago
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.
krimoc 1 year ago
@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!
ehelmink 1 year ago
Comment removed
krimoc 1 year ago
Plaese tell me the specifications of the motor thier torque and speed.. also the name of company
noveel1 1 year ago
@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)
ehelmink 1 year ago
Comment removed
kmowez 1 year ago
Hey you used labview for this system right?
Can you upload the code pls
kmowez 1 year ago
@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...
ehelmink 1 year ago
@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?
kmowez 1 year ago
@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..
ehelmink 1 year ago
this is pretty cool! are guys students in a university or something?
demollyon 1 year ago
@demollyon Yes, we are students of a university in the Netherlands. Thanks!
ehelmink 1 year ago
where can i find the rod joint you use for the middle of the platform?
zubairhussain123 2 years ago
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?
gan3ram4scientist 2 years ago
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! :-)
ehelmink 2 years ago
wow... tats wonderful...
i was askin about the picture dimensions in pixels..
gan3ram4scientist 2 years ago
Can you run this thing on a car/coach/lorry driving, braking and cornering? See how it copes with that. Should make an interesting video.
hrford 2 years ago
I think its possible.. We tried to build it on a RC car, but there are some problems.. The system requires a power source and a laptop.. Maybe you can build it? ;-)
ehelmink 2 years ago
In a real car you could possibly just use a 200 W inverter.
hrford 2 years ago
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!
ehelmink 2 years ago
Oh i know.. i takes 3 months to built the segway.. the difficult thing was to implement the pid on the arm 7 , because floating point is not supported in the NXT Toolkit.. Maybe i will you the NXT Motors for turning the plate.. i will just let you know when the project is ready.. so tot ziens
Fatzwonga 2 years ago
Oh.. Sounds nice! PID is not easy to work with.. ;-) I'll be waiting for your meassage..! Ich wünsche du viel Erfolg! Haha..
ehelmink 2 years ago
okay... i know it, but the usb driver is not officily supported by NI... anyway i like your applikation ...especially the demo mode is very cool ... Did you use the PID Toolkit ??? I have used it for my NXT Segway as you can see in my Videos ..
Maybe your demo would be a great show for a booth ... i would try to make this with the arm 7 Board and LabVIEW Embedded.. are there new plans for further demos....???
Fatzwonga 2 years ago
Yes i know.. Somebody of NI told me.. But its nice to work with! We used the PID toolkit. All this work is done in 7-8 weeks, so a lot of work, the find how things work etc. It this moment we have no further plans, cause our subject is finished/closed..
I saw some cool stuff on your youtube site! Asspecially the segway and its gyrosensor!
ehelmink 2 years ago
how did you measure the position of the ball ??? dms or is there a sensor in the ball ...
great application
Fatzwonga 2 years ago
The possition of the ball is measured by a standard webcam (logitech quickcam pro 4000). The video from the sensor in the cam is used with labview (national instruments), this app measures the possition in pixels (by contrast (black/white))
ehelmink 2 years ago
hey great... i know LabVIEW because i work for National Instruments :-).. so did you also use our Vision tools??? like vision development modul ???
dank je well for the quick response...
Fatzwonga 2 years ago
Aah okay, nice! Whe used vision tools for usb cause we had an usb cam.. We really liked it. But to (auto)set the preferences is difficult. You see a pop-up for the settings everytime the program is started.
ehelmink 2 years ago