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Mate Trouble: Rotary/Wankel Engine

casparrothcasparroth Member Posts: 3 EDU
Hi! Today I started designing a rotary engine, for fun. Although the design is really simple at this moment, but I'm struggling with the mates. Check out the model below to follow along.

Q1) I've made a very simple cam-follower that is supposed to control the valve timing (although about everything about the timing and rotation is wrong atm, but that doesn't matter), but I'm failing to get both the centre shaft cam tangent to the rocker arm, and the pin at the other end of the rocker arm to work the slider (both tangent and pin/slot don't work).

Q2) How do you guys make your internal gears? For my rotor's internal gear I used the 'Spur Gear' custom feature and then used a boolean to cut it from my rotor, but it's not exactly accurate or ideal. Tips?

Thanks in advance!!


  • john_mcclaryjohn_mcclary Member, Developers Posts: 1,864 PRO
    Can you make your document public so I can make a copy and edit some mates?

    One issue is your arm radius is slightly too low. You can see how the cam radius tangent line is above the radius tangent of the arm.
    Either make the arm a little longer or make the radius on the arm smaller. So that the cam is always on the Flat surface of the arm.

    Once that is done, I can't see why a tangent mate wouldn't work on the bottom pin. Unless it is just throwing an error because of the jam-up caused by the radius issue also.
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