Guide to Tuning Slider and Wheel

This page describes the procedure to tune slider and wheel sensors.

Slider/Wheel Operation

Sliders/Wheels are comprised of multiple buttons. When any of the buttons in a slider or wheel detects a touch, the slider state becomes active and the position is updated. From this state onwards, the slider state remains in the active state as long as the slider/wheel delta is higher than the slider/wheel detect threshold. The slider/wheel delta and slider/wheel detect threshold are operational until the touch is removed and processed again.

Tuning Procedure

In this example, two buttons and a three channel self-cap slider are configured. The two buttons are named B0 and B1, while the button sensors that form the slider sensor are Slider0[0], Slider0[1] and Slider0[2]. The data for the buttons and the slider/wheel is displayed in the data visualizer control panel view as shown below.

dv-data.png

1

Touch each button of the slider/wheel sensor (Slider0[0], Slider0[1], and Slider0[2]) and note down the delta values. The delta observed on Slider0[0] in this example is shown below.

inv-button-tuning.png

Configure the individual button's sensor threshold to half the value of observed delta value. In this case, the button threshold should be configured to 60.

2

Configure the calculated button threshold on Step 1 above as the slider/wheel detect threshold and verify that the slider sensor detects when the individual sensors are touched as you can see below.

sldier-tuning.png

3

Scroll over the slider sensor (back and forth between start and end corners) and record the slider/wheel delta on a CSV file using the file logger utility.
To use the file logger, follow the instructions below:

  1. Switch the slider/wheel to edit mode by checking the edit box at the bottom of the debug control panel.
  2. Open the file logger element, Configurations > Utilities > File Logger.
  3. Minimize the QTouch Data Visualizer view window by double-clicking on the title bar.
  4. In the file logger view, click the file browser and select the file name to log data.
  5. Click the slider/wheel Delta0 connector, drag it and plug it into the file logger socket as shown in the figure below.
  6. Now, click the start/stop button to log the data.
After logging is complete, remove the SliderDelta0 connection, uncheck the edit mode check box, and close the file logger.
log.png

4

Open the file log and identify the lowest SliderDelta0 value from the samples. A few samples of the SliderDelta0 collected from the Slider_delta.csv file are listed below.
103,102,101,106,98,92,86,82,78,76,78,86,0,118,113,109,105,102,100,106,102,93,86,
80,76,73,72,73,79,88,90,90,89,89,89,90,94,87,81,76,72,71,69,72,81,89,94,98,100,102

Configure the slider/wheel detect threshold to be less than (50~70%) of the identified minimal value "69". In this case, the Slider/Wheel Threshold is set to 48. Repeat Step 3 and Step 4 several times and tune the slider/wheel detect threshold based on the logs.

The buttons and slider/wheel data after the tuning is provided below.

after-tuning.png
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