ddot | A lightweight registry command framework | Command Line Interface library

For a project I have, I control a BLDC motor with it's own current controller.

To design a controller for the motor I fitted some time traces to the flowing function:

to capture the dynamics of the entire system, namely, motor, current controller/driver and load.

J is the rotor inertia, [kg*m^2]

r a dampening constant (linear friction)

tau is a torque constant [Nm/A]

u[t] a current input

der(der(phi)) is the angular acceleration

der(phi) the angular velocity

The fitted values represent the entire system more than good enough for a 'continuous' approximation of the motor, the load and the current controller/driver of the motor. With the control scheme, I give a signal u(t) in Amps, and I expect a torque and an angular velocity as an output. At the time I only needed the angular velocity, but I digress, this method worked fantastically, but was fitted and designed in mathematica.

I would like to build a much larger, and significantly more complex robotic system within modelica (Systemmodeler specifcally, however, modelica library 3.2.x), however I am having some issues.

My first attempt was:

However, when simulating this with another outside load (an external model), I have a lot of issues, from some those more experienced than I, I am told this form of modelling is 'one way' and not the 'modelica method' but more simulink in form.

Namely, it should be bi-directional, not just numerical outputs, in order to correctly react with the multibody external model, this will connect to.

My second attempt was:

Which when connecting to my larger multibody model, it does indeed work more like it's expected to, there is a reaction from this model, when external torques/loads are applied. However, when simulating this model to see how it fairs compared to the pure block model, they arn't the same by any means. I had to spend a lot of time trying to fit the inertia and friction data to get similar results.

SO my question is, what is the best method, to turn pure block models (mathematical ones) or atleast,my pure block model, into a more realistic model or atleast, the connecting outputs into more realistic, or I guess 'acasual' ones.

I would prefer not to use my second attempt, since I can't trust the values I had to adjust compared to the block to actually be correct, since they arn't fitted values to real world data, compared to my first model.

let say I have below data

I have an app which uses the armadillo library to do some matrix calculations. It compiles fine against the Accelerate.framework, but is rejected at the app store:

ITMS-90338: Non-public API usage - The app references non-public symbols...ddot, dgemm, dgemv, dsyrk.

These symbols are from the BLAS library and are included in Accelerate, but are apparently not public. Is there a way to use armadillo without getting this error?

I am trying to solve a coupled ODE using the DifferentialEquations package in Julia, and trying to implement a Continuous Callback to check when a certain variable becomes small enough, so I can terminate the integration. The functions xdot, ddot are defined earlier, and this is working fine without the cb = callback argument.

I'm having some difficulty installing quadprog on macOS under Python 3.6. I've tried numerous solutions but nothing seems to be working.

What I need to install is trajectory_planning_helpers and it needs quadprog. This is the error that I'm getting when I enter the command pip3 install quadprog:

From David Carlisle's answer to the post Embed LaTeX math equations into Microsoft Word, I learned that \dot{z} in LaTeX can be translated in MathML as:

Recently I have been working on a program that can convert TeX-generated PDFs to a certain form of text that retains some semantically meaningful style information such as subscripts and superscripts.

When debugging it seems that there might be something very unusual going on with the PDFTextStripper class.

Here is my TeXUtil class that does most of the work.

I'm trying to write a generic function to serialize to string a std::vector> and I want this to work for both cv::Point2i and cv::Point2f (both are typedefs of cv::Point_ with a specific T).

The function looks like this:

I want to get this snippet to work :