unistAR

Week 9 - Try to use a TRACKPOINT

Roles

We decided who does what in this project.

  • Minseop Kim: Connecting HoloLens and Arduino with bluetooth module.
  • Doyeon Kim: Connecting trackpoint and trackball to Arduino.
  • Heena Kwag: Develop HoloLens application by Unity for experiment.

First experimental design

We designed the experiment for testing selection task. We refered the paper, “Towards a standard for pointing device evaluation, perspectives on 27 years of Fitts’ law research in HCI”.

It was divided into two experiments depending on the position of the targets.

  1. All targets are in the field of view.
  2. All targets are out of the field of view.

In the second experiment, the experimenters need to move their head unlike the first experiment.

First Experiment Design

Advice from the professor

The professor looked through our first experimental design and gave advice on it.

Make it more specific

He said that we have to make our experiment more detail. For example, we have to decide the size of element, the distance between two elements, the order to click, and so on.

3D Fitts’ law

Most papers on Fitts’ law apply to 2D environments, so we should search papers on 3D Fitts’ law or Fitts’ law applying to AR environments.

Comparison

At first, we were going to compare our new input device to HoloLens’ gesture system. However, the professor insisted that they are too different to compare each other in the way they work. In addition, HoloLens gesture system has two behaviors (move and tap) and tap is too slow rather than move.

He suggested alternative ways.

  1. Use ‘dwell on’ click method.
    → Click is time-consuming behavior, so remove it from two systems and compare them. Actually, ‘dwell on click’ is not a good method to apply real-life situation but there is no problem to use it in the experiment.

  2. Make two input devices (trackball and trackpoint) and compare them.
    → Trackball and trackpoint work in similar ways.

  3. Use ‘descriptive’ study, not ‘comparison’.
    → If we will not able to find proper system to compare to our new system, then describe it, not compare the performance.

Use a trackpoint or find out the unique points of a trackball

We were planning to use a trackball instead of a trackpoint due to below problems.

  • To use a trackpoint, IC chip also has to be used. But it is too big to make a ring.
  • There was not as many references as the trackball.
  • There is no click system in the trackpoint. We have to implement a click using a pressure sensor.

However, he recommended trying to use a trackpoint. He thought that there is a certain novelty value in a trackpoint because pressure-based input(=trackpoint) was not studied much more than movement-based input(=trackball). If we want to use a trackball, then we have to find out the unique points of trackball unlike other movement-based inputs.

Find a way to connect a trackpoint and HoloLens

After meeting with professor and mentors, we decided to try to use a trackpoint.

We searched a way to connect a trackpoint and HoloLens. Originally, we were planning to communicate them directly with USB. However, the USB port of HoloLens is used for charging, not tranfering data. To connect the external device to HoloLens, it needs to use bluetooth communication. So we proposed four alternatives.

1) Connect a trackpoint and Arduino with a bluetooth module using USB shield

Disassembled trackpoint can communicate with USB port, so connect it to Arduino using USB shield. Then connect Arduino and HoloLens using bluetooth.

2) Disassemble other bluetooth keyboard which has a trackpoint

In case of bluetooth keyboard, there are a trackpoint and a bluetooth module on the chip.

3) Attach a bluetooth module on the chip

4) Make a multiplayer application

Make unity application for experiment allow to access multi-user. Then, a computer connecting with trackpoint and HoloLens access it at the same time. User manipulates the cursor using the trackpoint.

Result

We thought the third plan would be too difficult and time consuming. So we decided to buy another Bluetooth keyboard for the second plan while going through the first plan. If all of the above plans do not work well, we will proceed with the last plan.

To-do list for next week

  • Search the papers on usability test for HoloLens input.
  • Begin to develop the experimental application using unity.
  • Try to connect a trackpoint and Arduino with a bluetooth module using USB shield.