Category Archives: Sound

Some Assembly Required

Integrating all the pieces into one test platform. The test could be to move a collection of physically-based spheres (easy collision detect) from one area to another. Time would be recorded from the indication of a start and stop (spacebar, something in the sim, etc). Variations would be:

  • Open loop: Measure position and pressure, but no feedback
  • Force Feedback (Phantom) only
  • Vibrotactile feedback only
  • Both feedbacks

Probably only use two actuators for the simplicity of the test rig. It would bean that I could use the laptop’s headphone output. Need to test this by wiring up the actuators to a micro stereo plug. Radio Shack tonight.

Got two-way communication running between Phantom and sim.

Have force magnitude adjusting a volume.

Added a SimpleSphere class for most of the testing.

Random bits

I think I know what the vibroacoustic study should be. I put an actuator on the Phantom and drive wav files based on the material associated with the collision. I can use the built-in haptic pattern playback as a control. To make the wav files, it might be as simple as recording the word, or using a microphone to contact a material, move across it and lift off (personally, I like this because it mimics what could be done with telepresence. The use of multiple sensor/actuator pairs can be used in a later study.

Which means that I don’t actually need the Phidgets code in the new KF hand codebase. I’m going to include it anyway, simple because I’m so close and can use it later.

Come to think of it, I could put an actuator on a mouse as well and move over materials?

Tasks for today:

  • Finish getting the Phidgets code working in KF_Hand_3 – done
  • Start to add sound classes – done inasmuch as sounds are loaded and played using the library I wrote. More detail will come later.
  • Start to integrate Phantom. Got HelloHapticDevice2 up and running again, as well as quite a few demos

vector<tuple<float, float, string>>::iterator it = sourcePositions->begin();

C++ is like being in a candy store, full of a huge variety of bright, shiny treats that can blow your hand off if you don’t pay attention.

  • Finishing up adding multiple sound capability per test attempt. Because I’ve been away from C++ for a while and I like to try new things, I poked around with tuples for a while, which are kind of neat. Then I decided to put them into a vector and access them. That lead to code like this:
    • vector<FOURF_SAMPLE_TUPLE>::iterator it = myVector.begin();
      while(it != myVector.end()){
      	float sourceX = get<EMITTER_X>(*it);
      	float sourceY = get<EMITTER_Y>(*it);
    • That is *not* the most intuitive code I’ve seen. I mean, it makes sense, and given the limited set of overloadable characters, ok. But I think “[” and “]” would have been a better choice than “<” and “>”.
  • Got the multi sound playing and the results output to .csv. Next is to get the xml setup files running.

Pulling everything apart and putting it back together

  • Adding multiple sound playback
    • Rework the output to handle multiple sounds. This means one TestResult per sound. However, the result cannon be associated with a sound, so for each release, all the emitter sources will have to be included. Later analysis can be used to determine the best fit. Note also that the number of attempts may be greater or lesser than the number of emitters.
  • Need to use the XML to write out and read in just the configuration values
  • Need to save multiple source positions in TestResult. Added bad code at the point to continue.


  • Meeting with Dr. Kuber.
    • Add a “distance” component to the test and a multiple emitter test
    • Got a bunch of items to add actuators to: Hardhat, noise-blocking headphones, and a push-to-talk mic.
  • Added name and gender fields to the GUI and cleaned up the menus
  • Working on adding multiple sounds
    • Added a ‘next’ button. Once pushed, the sources can show until the center is clicked again.
    • I think the test should have options for how the sounds are added
      • Permutations (A, then B, then C, then AB, AC, BC, ABC)
      • All (Going to start with this)
      • Random?
  • Added variable distance

So that’s what happens when a programming language gets old…

  • Continuing with the test exec. I’m also going to need a class that records the data associated with each test segment.
  • Ran into a… Well, I don’t want to call it a bug. Let’s say that C++ is showing its age. FLTK uses char*. Most of Windows uses wchar_t. They don’t play well together, so I spent about half of my time working out the best way to convert between them. It’s this:
  • void setSoundFileString(LPCWSTR wps){
    	soundFileString = new wstring(wps);
    	string str(soundFileString->begin(), soundFileString->end());
    	sprintf_s(soundFile, "%s", str.c_str());
  • I mean really!? Good grief.
  • Got a lot of the exec built and running. Clicking on the center button fires the sound, and you can drag to where you think the sound is. I am not all that accurate. It could be a frequency thing though. I’m running a low 10-20 HZ signal. The test should definitely try different frequencies.

FLTK and FLUID. Simple, Good Stuff

  • Starting to put together the actual test framework. Found a good open source synthesizer (ZynAddSubFX) that I used to create a pure tone that I then cut down to one second with Audacity. It’s important to note that this app only works with MONO sounds.
  • Building up the class that will handle running multiple sessions.
  • Just a quick shout out to FLTK. I have been adding and adjusting the GUI all day long as I figure out how to run the tests. To add fields, adjust positions and just generally futz around, all I have to do is use the FLUID gui IDE, export the layout as C++ code, add in stdafx.h and compile. It all just works. A great piece of code. FLTK_rocks