Recent content by madgorillaz15

I think I accidentally ignored this post?! But it seems like you really know what you're talking about. I was recently doing some research online about my issue and rotation matrices showed up. The (potential?) problem: I'm not sure how the rotation matrices idea works (I'm hoping you can help...

Good news: I understand the bolded! :D But I'm assuming that you want me to ignore the fact that the blue curve is negative. About the red: Not sure how you ended up with that answer. What did you plug in for the change in speed and time? Lastly, does multiplying the acceleration by the radius...

Hmm thanks for your interpretation. I think you probably have the right idea but I'm not sure about your actual numerical answers. First, I'm not sure why you suggest the blue curve is the velocity. The blue and the green are on the same plane as the rod, the only part perpendicular to the rod...

Oh yes. That makes sense too.

OK. So I just finished gathering data. I put the accelerometer at the end of the rod, but I got some weird things. First, note that I just used a basic smoothing filter to get an idea about the shapes, but I'll look more closely about how I should filter it later on. I have three plots attached...

OK thanks for your comment (also sorry for the late reply). If it's ramping up, then then I think at that point the acceleration should be linearly increasing, and then when it's ramping down, it should linearly decrease. If its moving constantly, that means that velocity is a constant number...

1) you're correct about the bolded. The shaft does not move up and down. It indeed only rotates about its axis. 2) With your derivation, are you trying to show me that the acceleration should be the second derivative of the position. I think that makes sense... 3) Thanks for clearing up the...

Ultimately, I'm interested in the measuring the instantaneous torque of the rod (the shaft is that of a motor, so the motor is moving everything). So basically, I want to measure the torque the motor is producing using acceleration.

Homework Statement Imagine this: A rod is attached at one end to a rotating shaft. So, as the shaft rotates from 0 to 90 degrees back-and-forth (in the xy plane), so does the rod. My goal is to measure the instantaneous acceleration of the rod while its moving. I have a few 3-axis...

Yeah, I just checked and we aren't allowed to treat it like an angle. Furthermore, I was mistaken in saying that c was a part of a circle-it's actually an ellipse. How does that change the answer?

Hi titasB, I apologize, but as in my other reply, does this answer change if the big arc is actually half an ellipse, and not have a circle as I first assumed?

Can I ask, are you treating c like an angle? Also, after speaking to a friend, I was mistaken in assuming that those arcs belonged to quarter circles. In fact, they belong to an ellipse (so the entire big arc you see is actually half an ellipse). How does that change your answer? Thanks though.

Homework Statement In the attached drawing, find R in terms of L and c. Also, at the bottom of the picture I wrote something wrong. I said c, which equals 0.5, is the arc-length of each semi-circle, but I really meant to say each quarter circle. My bad. I'm not given a number for L so that can...

Oh, I think I get what you're saying. So you want me to attach a rod or some lever to both sides of the bottom mount of the servo, and then have a strain gauge on each side. But how would this give torque? When would the lever stretch?

Well I'm a bit confused by your picture. Are you proposing I attach some sort of rod or arm to the shaft of the servo, and then put strain gauges on the sides of that? And by servo mounting brackets, do you mean the areas that the arrows are pointing to in the picture I uploaded? I just want to...