1. A problem was solved. The clockwise rotors were fitted with clockwise propellers, and, the anticlockwise motors are fitted with anticlockwise propellers. This was not the situation before.
How did we know that? An anna advised us to use a piece of paper over a running motor. If the air and paper was drawn into it, then, the thrust is downwards- hence, the placing is correct. Otherwise, the wrong propeller is on the rotor. So, we changed it that way.
2. Ma'am said to proceed in two ways separately-
2.a. get the penta to hover and fly, use the data so obtained, in cubic spline interpolation to get the motion equations.
2.b. do it the intech, AUS paper way.
This means a lot more work.
Today was a waste of time in college. I wish I hadn't gone. College would have been a complete waste of time, if I hadn't seen my good friend, Santosh. It was nice to see him again. I must have bored him out because I talked alot and learned alot from him!
Derived the center of mass of the pentacopter. Have assumed that the mass of the carbon fiber rods are distributed on the point masses of the motors.
How did we know that? An anna advised us to use a piece of paper over a running motor. If the air and paper was drawn into it, then, the thrust is downwards- hence, the placing is correct. Otherwise, the wrong propeller is on the rotor. So, we changed it that way.
2. Ma'am said to proceed in two ways separately-
2.a. get the penta to hover and fly, use the data so obtained, in cubic spline interpolation to get the motion equations.
2.b. do it the intech, AUS paper way.
This means a lot more work.
Today was a waste of time in college. I wish I hadn't gone. College would have been a complete waste of time, if I hadn't seen my good friend, Santosh. It was nice to see him again. I must have bored him out because I talked alot and learned alot from him!
Derived the center of mass of the pentacopter. Have assumed that the mass of the carbon fiber rods are distributed on the point masses of the motors.
Now, I am looking at the lecture by Prof. Amitabh Ghosh from the dynamics of machines series specifically lecture 3.
There is a problem with just considering the 6 masses. The rods(carbon fiber), circular sheets and the 5 stands for each motor leg, contribute .047Kg*5=.235 Kg.
The whole pentacopter weight is 1.185 Kg.
Each motor has a weight of 0.085 Kg.
The mass of the battery is 0.525 Kg.
Length of a rod is 23 cm.
So, I made the assumption that 0.047Kg was distributed on a mass of 0.085Kg! I don't want to sound ridiculous, but I apparently tried to have to avoid having to include the rods into the center of mass derivation. It would be time consuming, because, these are five uniform rods at angles to the the considered axis. Apart from five point mass motors and a big battery.
So, on substituting the derived formula, making the assumption that the mass of the rest of the penta could be distributed on the motor masses, the center of mass of the pentacopter lies at 0.942 meters from the left hand most two motors(assumed to be parallel to the y axis i.e. becomes the y axis when x1=0.)
While the entire length of m2, m1 to m5 is 0.41607 meters.(as in the first image,)
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