# Search results

1. ### Angular momentum direction

In 3-D dynamics why is the angular momentum not aligned with angular velocity? Does this mean H = Iw is wrong in 3-D ?
2. ### Spacecraft Mission Design

Thanks for a quick reply. I can't find the password in the book. Anybody knows where it is ? Can anyone who has access to it provide me ? Its around 1 mb only.
3. ### Spacecraft Mission Design

I got this book(https://www.amazon.com/gp/product/1563470411/?tag=pfamazon01-20) by Charles brown from my institute library. Unfortunately they have misplaced the floppy disk containing Spacecraft Mission Design software- ORBWIN. Can anyone share the software or give me ideas on how to get it ...
4. ### Implementing digital PID control

Thanks for replying. i have a simpler query now : Suppose I use a proportional control to drive a motor. Measured rpm = 2000, Required rpm = 5000, Error = +3000. Control signal = K * Error. Now how should I apply this control signal to increase in voltage so as to attain the required rpm ?
5. ### Why are geosynchronous orbirs in equatorial plane circular?

Geostationary orbit(s?, can there be more than one geostationary orbit?) are geosynchronous orbits in equatorial plane.So obviously I mean geostationary orbit. Hope I'm right
6. ### Why are geosynchronous orbirs in equatorial plane circular?

This isn't a homework problem. Difference between circle and ellipse is that their eccentricities are 0 and (0,1) respectively.That doesn't seem to strike anything to me or am I too dumb ??
7. ### Implementing digital PID control

I want to control the rpm of a brushless motor with ESC(Electronic speed controller) using PID control. Suppose my motor is rotating at 2000 rpm detecting using hall sensor setup.Now I want it to run at 5000 rpm.The speed will be controlled by PWM signals generated by PWM module( 16-bit i.e...
8. ### Why are geosynchronous orbirs in equatorial plane circular?

Anybody can answer my query ? thanks !
9. ### any genius answer my question

I think stars flicker more than planets as they are lot further away.The intermediary medium has varied properties so they appear as blinking.