2020 Trade Shows are cancelled so let DYNOmite bring them to you...

Trade Show Update

10/30/2020

Trade Shows have been cancelled for 2020 and we are disappointed as you are. But in anticipation of this reality, we have been working hard to create a new-to-the-world virtual booth for our devoted Customers. You will hear more about this in the next weeks, but look for:

  1. Live streaming content with industry experts
  2. Demonstrations with service techs of our equipment
  3. Live chat with Sales and Service staff to discuss industry needs and innovations
  4. Watch as some of the most popular SuperFlow and DYNOMite products are being built
  5. the coolest opportunity the industry has ever experienced – YOUR chance to interact with our Innovation team to finalize versions of software and controls

DYNOmite views this year as an opportunity to engage with you in ways we haven't been able to in the past. Please visit our show page to register for additional information as it becomes available.

Data Aliasing


Read about the phenomenon of aliasing in digitally recorded data.

Advanced | 07.17.20

What is Data Aliasing?

Aliasing, in the recording of dynamometer data, is the inducement of anomalies in the captured signals as a result of using too long a sampling interval. In video capture, using too slow a frame rate, you see aliasing as the slowing or reversing of a spinning wheel’s spokes.

During engine testing, if the selected sampling interval is too long, high-frequency events may induce low-frequency humps and bumps into the recorded data. Aliasing effects can vary with things like the test RPM!

Consider the torque channel, it is subjected to a high/low oscillation every time a cylinder fires. So, it’s data inherently contains a ripple – the frequency of which varies with RPM. That is why you see the magnitude of aliasing errors change as the RPM frequency comes in and out of phase with a data-acquisition system using some fixed sampling interval.

Accurate capture theoretically requires a sampling interval less than one-half the inverse of the highest Fourier frequency component within the sampled channel. This is referred to as the Nyquist interval.

The effects of aliasing in the recorded data may be avoided by filtering (e.g. electronically dampening with capacitors) the source signal to remove any frequency components that are higher than those required in the captured data.

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