has anyone done this?

[lapachacha]

i want to make a CAM in pro-e.how to do it? plz help. been desperate all along..will i need the datum graph for that?..what is V,T and H in the graph?...please relate it to CAMSss

 

[SRINIVASANIYER1]

It is possible to design cams (mechanical cams) in Pro/E for different motion profiles like, SCCA, Cycloidal etc. You should be using the mechanism application for both Analysis and Synthesis. One can also use equations for the cams i.e. define datum curves through equations or Evalgraph and perform the analysis using the Motion analysis module. An easier method would be to Synthesise the cams by defining the motion profile of the follower and constant velocity to the Cam itself.

 

[lapachacha]

yes but how? i m new to pro-e...plz can you outline the steps...what do the symbols V,H and T on the datum graph represent?...how do i relate this graph with the cam profile i want?..it all starts with the displacement diagram first

 

[kenppy]

You'll need to be a bit more specific about what type of cam you want (plate cam, barrel cam...?) Harmonic path or have you a formula? Maybe a picture, it will all help.

 

[neuronex]

A short little CAM profile tutorial here...

 

[lapachacha]

neuronex thank u for the tutorial.i already had a glance thru it some days back but the datum graph holds nightmare for me..i m unable to appreciate its relevance with CAMs specifically?...how to relate cam parameters such as base circle,prime circle,pressure angle,pitch circle etc with the datum graph..

look what i intend to do is that i have two steel rods hanging from the ceiling.i need to shine a laser beam onto the bottom ends of the rods .now for this i have a small box(very light weight)(consider a shoe box) having a laser pen at the middle.the angular distance between these two ends of rods is 120 degrees as SEEN from the ground where this box is.so i need to give a 120 degrees rotation to the box to serve my purpose..dat is..first laser spot on the 1st rod then on 120 degree sweep..to the other end......i intend to have this done with a cam coupled with a stepper motor.

so for a cam rotation of ,say,90 degree,i want the box to rotate 120 degree(this is simple harmonic and a oscillating cam problem).i.e a rise of 120*pie/180*the length of the box=gives the chordal/arc lenght which gives the rise.and a 120 degree return stroke for a CAM rotation of 90 degrees.no dwell...this comes out to be 180 degree total..not closed.i.ee not 360 full degrees.

how to design the cam profile ? i have tried this on solidworks as it has a toolbox and cam templates but yet again i do not understand the nomenclature and input it requires from me..the terminology it uses just doesnt coincide with the conventional nomenclature of cams.

HEEEEEEEEEEEEEELPPPPPPPPPPPP!!!!!!

 

[SRINIVASANIYER1]

Pardon my understanding if wrong. Fora SHM, one need not use a CAM. You can achieve it through a 4-bar link chain. a 4-bar link mechanism would be easy to manufacture too and would give the desired results with a constant velocity motor.

 

[lapachacha]

hellooo sri...cams are suitable for such applications...linkages are inherently complex...have u worked with camtrax? have u seeen grooves in cams...solidworks makes cams for u but has grooves in them which i do not want...need ur help in these areas

 

[SRINIVASANIYER1]

My post was based on the vague idea that I perceived from your description. From what I perceived, motion profile is not very critical meaning, the velocity / acceleration and Jerk are not important, but the ability of the mechanism to move a certain amount in a certain time or motion angle is important.


I have not used camtrax. My experience of cams comes from designing offset printing machines, wherein multitude of linkages and cams are used. For reference I used reference books. Computers and software were a rare commodity then

!!!


May be a sketch of what you desire would help us to understand.

 

[lapachacha]

plz gimme ur email id so dat i can mail u a video of wat i desire..