ENH: implement a linear varying center of mass for Hybrid motors

[ompro07]

A method was added that allows calculating the variation of the center of mass of the hybrid motor using a linear interpolation.

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A method was added that allows calculating the variation of the center of mass of the hybrid motor using linear interpolation.

[Gui-FernandesBR]

@ompro07 can you add a simple example of your feature working ?

[Gui-FernandesBR]

Hey @ompro07 nice PR from your side. I've pointed 3 major comments that I think we can discuss in more details in order to improve this implementation and the next ones

1 . I definetely suggest we include an example of hybrid motor usage, at least for facilitating our verifications on future pull requests. I am suggesting the following example:

hybrid = HybridMotor(thrustSource=2000,   # These are dummy numbers, please add what makes more sense in each field,
                    burnOut=5, 
                    distanceNozzleMotorReference=1, 
                    grainNumber=1, 
                    grainDensity=1000, 
                    grainOuterRadius=10/2000, 
                    grainInitialInnerRadius=5/2000, 
                    grainInitialHeight = 0.3, 
                    oxidizerTankRadius = 127/2000, 
                    oxidizerTankHeight= 2, 
                    oxidizerInitialPressure= 60, 
                    oxidizerDensity= 500, 
                    oxidizerMolarMass= 44/1000, 
                    oxidizerInitialVolume= 1/100, 
                    distanceGrainToTank= 1/10, 
                    injectorArea=1/10000, 
                    grainSeparation=0, 
                    nozzleRadius=0.0335, 
                    throatRadius=0.0114, 
                    reshapeThrustCurve=False, 
                    interpolationMethod="linear")
# Btw I think it would be nice having some standard values for some of these arguments

and then the hybrid.info()method will return the following:

2. I also believe we need to implement a simple unit test to guarantee next PRs will be verified using github actions

3. Finally, the info() and allInfo() method can be improved a little bit for HybridMotor class,

[Gui-FernandesBR]

Comments stated below, nice work anyway

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[Gui-FernandesBR]

Never saw such behaviors... we need to adrres pytest failure before merging

[Gui-FernandesBR]

Thanks @MateusStano for solving the problems with github actions