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I think you can change how the steps change between gridlines with the grading option. If you have some entities that should not influence the grid set priority to zero (for those entities). Then choose the largest grid step you want for the global settings and and the smallest (0.5mm) for the arrays_grid. You should manage to control how the grid changes away from the arrays_grid.

When using a long line as "normal" edge source, the discretization will result in one edge being the actual source and rest of the line being discretized as PEC filament. This can lead (depending on the excitation frequency, the length of the source line and the setup) to inaccuracies due to the additional capacitance introduced be the PEC filaments. An alternative that is, in most cases, a more accurate source representation is using the "Distribute Along Line" option, the source is equally distributed over all the discretized edges of a line element (see image, right). That prevents any PEC filaments and therefore makes the injection of the signal more realistic. Time delay = distance between the transmitter and receiver*sin(theta)/c where theta is the angle of antenna. I would suggest looking into antenna array literature for theoretical background on calculating this quantity.

You must be referring to this: This is windows configuartion related issue. You might not have access to log counter data, try logging in as an administrator. Later you can add user to the Performance Logs User Group. Look at this page for more details: https://learn.microsoft.com/en-us/windows/win32/perfctrs/limited-user-access-support

This is windows configuartion related issue. You might not have access to log counter data, try logging in as an administrator. Later you can add user to the Performance Logs User Group. Look at this page for more details: https://learn.microsoft.com/en-us/windows/win32/perfctrs/limited-user-access-support

Note that the above is only true in the case of a harmonic signal, which is why Sim4Life does not provide the RMS by default. It is up to the user to calculate the RMS based on their knowledge of the signal. If you are interested in B1+/B1-, the rotational components of B1 are by definition constant in time and so their RMS magnitudes are equal to their absolute magnitudes.

If you click on Network Analysis in your Analysis tree, what is your Reference Impedance? It is set to 50 ohms by default, but you have change it based on the Input Impedance for the coil before plotting the S11 curve. Plot the complex Input Impedance. At resonance, the imaginary part will be zero (the circuit is purely resistive). So at the desired resonant mode / frequency, you should find the corresponding real value, and set this value as the reference impedance to plot |S11|. [image: 1714032407782-a7146e86-302b-43e7-9dd1-9aac7dc76ccb-image.png] [image: 1714032424033-6f536c46-f9f2-4d5a-b787-cfdb97521404-image.png] [image: 1714032432837-5730b440-37ea-4190-824e-1fac4e45155a-image.png]

When you used the Mask Filter, did you check the option 'Invalidate Masked Values'? This will set the Background to NaN, which should hide it. Otherwise, the Background value will be changed to a user-defined replacement value, which would still show up during visualization.

The first method might not be working if your spline doesn't have a parametrization. If you click on the spline in the Model tree and don't see a list of points in the Controller window, then the information is no longer available and you'll have to stick to the second method.

To perform such a study, define your region or quantity of interest, then parametrize it. After a quantity has been parametrized, you can run multiple simulations using the built in Sweeper feature or using the Sim4Life Python API. There is an example in the Sim4Life manual titled 'Parametrized Patch Antenna' that shows how to use the Sweeper feature. If using the Python API, the easiest way would be to create a baseline simulation by hand, then right-click on the simulation name and select To Python. Then you would find the quantity of interest in the auto-generated script and assign it to a variable instead of the hardcoded value. Using a simple loop in Python, you can create multiple simulation that have identical setup except for parameters of interest. In your example, multiple simulations would be run with identical setup except for the grid resolution within a region of interest (e.g., a wire block surrounding a region of interest is placed in a manual grid settings folder, then Maximum Step is changed from 0.3 to 1.0 mm). Then in Analysis you extract a quantity of interest and compare how this value changes as a function of grid resolution. If the change in the value is small as you increase resolution, you can proceed in future simulations with a coarser resolution to save on run time. The exact convergence of the value needed depends on your application.

Thank you very much. This fixed the issue. This was related to Ares also.

Hello, Sorry I am facing an issue with moving antennas to different locations based on the steps above. I used three points on the skin and calculated the transformation between static and posed states. I used this transformation to transform the antenna position to the new position (using RigidTransform and ApplyTransform functions). However I get errors that the antenna source edge is within a solid. I have changed priorities during voxelling providing antennas higher priority but the errors still exist. What can I do? I would like to move antennas in a similar fashion to how soft tissues deform. Thanks Vignesh

Hi, Thank you. I tried it but would like to plot the fields on a grid between antennas (as shown in red in the image). It is easy when the model is static but when posed, I am not able to get a grid at an angle. Thanks [image: 1710200782830-dd141418-49f3-4854-a083-853ccfa690dd-image.png]

That's great to hear! Thank you so much for sharing your experience. I'll explore the option of implementing something similar for EM simulation.

Hi Bryn, I would like to ask a question regarding posing. My aim is to detect the variation in bone position from the skin in different poses (hypothesis being: as the soft tissues deform, the bone wont always be at the same position wrt the skin). I currently have 8 antennas placed around the skin which are supposed to mimic wearable antennas and I would like to move these antennas along with the pose. But if I link these antennas to the bone using "link-parent tool", the bone is always at the same location wrt to the bone irrespective of the pose. But I cannot link the antennas wrt to the skin as the antennas dont move with the pose. How can I do this? I would like the antennas which are placed around the skin to similar to the skin rather than the bone? Based on the first video in this chain, triangular meshes can be posed similar to the body. If I convert the antennas to meshes and then pose it, will I be getting the same issue i.e the bone is always at the same location wrt to the antennas? Thanks

A simulation can end in a couple different cases: If the specified level of convergence is reached, or if the specified number of periods are simulated. In the case of that tutorial, the simulation is set to run for 15 periods, and so it ended before a -50 dB convergence was reached. Convergence is a spectrum, and the level of convergence required for a given application is up to the user's discretion.

@bryn Thank you Bryn. Managed to find a version that wasn't corrupted! Hope you have a nice day :)

Thanks Ofi. How can I fix this or is this something I need to account for?