Tridef3D

DIY VR Headset for $80 (DIY VR Part 2)

KillerRobotics, , , , , 3 Comments

IMG_1817

The purpose of this series of posts was to look at ways to experience VR at home for the lowest cost possible. In Part 1 of DIY VR, we took a look at using a smart phone and a Google cardboard compatible headset to stream computer games to the phone in stereoscopic 3D. The main problem with this approach was that it was still relatively expensive as it required a smart phone (iOS or Android) to function.

Now in part 2 we will look at building a VR headset from scratch. My initial goal was to do this for under $150(USD), however after shopping around and changing some parts out for alternatives I managed to get this down to around $80. So let us get started.

The parts required are:

  • Toggle Flick Switch
  • 2x LED
  • 1x resistor 150 Ohm
  • 1x Micro USB cable (at least 2 meters long)
  • 1x HDMI Cable (thin ones work best as they hinder movement less, also at least 2 meters long)
  • Some jumper wires
  • DC Adapter plug 5V 3A (Raspberry Pi compatible one works great)
  • Push Button
  • Google Cardboard Compatible VR Headset (I recommend one with a phone compartment door that opens as it gives better access than the ones which uses a tray that slides in)
  • 6DOF MPU 6050 3Axis gyroscope and accelerometer
  • Arduino Micro (can use off brand alternative)
  • 5inch RaspberryPi LCD Screen 800×480 with HDMI interface

All of these parts can be acquired on AliExpress for about $80 ($82.78 to be precise), as shown in the image below:

Resistorflick_switchwireDC AdapmicroUSBHeadsetpushbuttonledMPU6050lcdHDMIarduinoMicrototals

You will also require Tridef3D or similar software (there are some free alternatives, but I have not had a chance to give them a try at present). Tridef3D is used to convert any Direct X 9/10/11 game into stereoscopic 3D. Tridef3D offers a 14-day free trial, which is plenty to give this a try. The full version of Tridef3D retails for $39.99.

Now that we have all the required components, let us begin with the assembly.

The assembly comprises of 3 main elements:

  1. The Arduino Micro circuit (containing the MPU 6050, push button and led)
  2. The Wiring (providing connectivity to Arduino Micro and power to Screen)
  3. Inserting the screen in the headset and connecting the micro USB cables as well as the HDMI cable.

The Arduino Micro circuit

The diagram below illustrates how the different components need to be connected to the Arduino Micro:

vr_bb1

The push button uses digital pin 5 and the MPU 6050 is connected to the Arduino Micro as follows:

– MPU 6050 SCL pin to Digital Pin 3 on Arduino

– MPU 6050 SDA pin to Digital Pin 2 on Arduino

– MPU 6050 VCC to 5V pin on Arduino

– MPU 6050 GND to GND pin on Arduino

The code to be loaded on the Arduino is as follows:

#include <Mouse.h>
#include <Wire.h>
#include <I2Cdev.h>
#include <MPU6050.h>

MPU6050 mpu;
int16_t ax, ay, az, gx, gy, gz;
int vx, vy;
int inputPin = 5;
bool enableMouse;

void setup() {
Serial.begin(9600);
Wire.begin();
mpu.initialize();
enableMouse = true;
pinMode(inputPin, INPUT);
if (!mpu.testConnection()) {
while (1);
}
Serial.println("Running...");
}

void loop() {
int val = digitalRead(inputPin);
if (val == HIGH) { // check if the input is HIGH
//Place logic here to execute when button is pressed
//Disables mouse movement while button is pressed, this allows you to set your view angle easily.
enableMouse = false;
}
else
{
enableMouse = true;
}
if(enableMouse)
{
mpu.getMotion6(&ax, &ay, &az, &gx, &gy, &gz);
vx = -(gy)/150;
vy = (gz+100)/150;
Mouse.move(vx, vy);
delay(20);
}
}

Just note that the orientation of the MPU 6050 makes a difference to which of the axis of the gyroscope will be used. For the above code the MPU 6050 was mounted on the side of the headset as shown in the pictures below:

IMG_1795

In the event of the MPU 6050 being mounted with a different orientation you might have to substitute between the gx, gy and gz values until the desired configuration is achieved.

For my configuration I am rotating around the Y and Z axis.

Also the numbers associated with calculation of vx and vy might have to be tweaked to get the results (movement speed etc.) you desire.

I also added a push button, that when pressed temporarily disables the gyroscopic mouse movement. This is useful when you want to reset you point of view in games.

I attached all the parts of this circuit to the VR Headset using double-sided tape.

The Wiring

In order to have as few cables as possible connecting to the VR headset I modified the USB cable so that it pulls external power from a DC power adapter (a single USB port will not be able to power both the Arduino and the 5 inch LCD) as well as splitting into 2 micro USBs on one end (one only provided power to the LCD and the other one both power and connectivity to Arduino.) the below diagram shows how the wiring is connected:

VR2_bb

For reference a USB cables contains 4 wires:

  • Red wire – +5V DC
  • White or Yellow – Data connectivity
  • Green – Data Connectivity
  • Black – GND

I also included a switch to turn the power on and off (this is useful to turn off the mouse functionality until it is needed, otherwise it will interfere with mouse movement when it is not desired) as well as an LED to show when the headset is powered on.

IMG_1807

Inserting Screen in Headset and connecting all the wiring

The LCD screen is held in place by the clamps in the headset used to hold a phone (it is a snug fit). Then simply connect the 2 micro USBs to the LCD and Arduino respectively (ensuring the plug with the data connections is plugged into the Arduino and that the power only micro USB is plugged into the power socket on the LCD display). Try to run the cables in the extra spaces in the Headset around the screen in order to keep them out of the way.

Lastly connect the HDMI cable to the LCD.

The assembly is now complete.

IMG_1817

Connecting headset to PC and setting up software

To connect the headset to your PC do the following:

  1. Plug the DC adapter into mains power.
  2. Plug the USB connector into an available USB port in your PC.
  3. Connect HDMI cable into and available HDMI port on your PC graphics card (You can use a DVI port with an adapter)

Go to display settings and click on detect displays, then set Multiple displays to “Duplicate these Displays” and make sure your resolution is set to 800×480.

Open up Tridef3D and start-up a game.

You might have to play around with each individual games graphical settings as well as mouse sensitivity to get the best results.

For future enhancements I will look at getting a higher definition LCD screen and also work on head movement tracking by using infrared LEDs and a Wiimote (Wiimote used as a IR Camera).

And there you have it a DIY VR Headset for $80. Give it a try.

Here is a short demonstration video:

DIY VR Headset for $80 (DIY VR Part 2)

DIY VR – Part 1

KillerRobotics, , , , , , 3 Comments

In this post we will look at ways to experience VR at home for the lowest cost possible. In Part 1 we will look at using your smartphone and a Google cardboard compatible headset to stream computer games to the phone in stereoscopic 3D. Basic “head tracking” will be achieved by linking the mouse look in the games with the gyroscopic sensors of your phone.

There are many applications available to achieve the above mentioned and we will look at a few options available, comparing features, performance and price. All of the mentioned software have free trial versions available in the event you want to give them a try. All you will need is a smartphone (iPhone or Android), a PC capable of running some Direct X 9 3D games and a Google cardboard compatible headset (one with head-straps will work best).

OLYMPUS DIGITAL CAMERA

All my testing was done on an iPhone 6S, a 2012 MacBook Pro Retina (Nvidia GeForce 650M 1GB) running windows 7 using Boot Camp and a SensofinityVR headset.

The games I used to test were Doom (original), QuakeHD, Dear Esther, Subnautica, Minecraft and Fallout New Vegas.

We will be looking at 3 different products (All of which consist of a phone app and a server windows application) that stream computer games to your phone and also link the games mouse input to the phones gyroscopic sensor. They are TrinusVR, KinoVR and IntugameVR.

First let us look at Tridef3D, a software product that will be required for the best results by all the before mentioned VR Streaming software products.It converts the game screen image into stereoscopic 3D before it is streamed to the phone.

Tridef3D

As mentioned above Tridef3D converts any Direct X 9/10/11 game into stereoscopic 3D, and I can say this software works great. Just note that its website states that it does not support VR headsets, but this is not the case if you enable windowed mode using this script. Tridef3D sells for $39.99 directly on the company site, however there is a free trail version available.

Most of the games I tested worked best in windowed mode except for Doom and QuakeHD, which only worked in full-screen mode.

Now let us have a look at the VR streaming software options. Firstly with all the mentioned software products, one of the most important things to configure correctly is mouse sensitivity. This is extremely important as getting this wrong can result in slow or jerky head-tracking which can cause the user to feel sick.

TrinusVR

Of the 3 products looked at TrinusVR was by far the best from an interface and general usage perspective. I also found it to be the most stable with the least amount of issues. At the time of my testing there was however no support for USB tethering in iOS.

I did experience issues connecting the phone to the hotspot created by the TrinusVR server software, and it appears that the phone is not assigned an ip address.

When I connected the phone to my MacBook via my home Wi-Fi network performance was extremely slow and unplayable.

I got around these issues by creating a Wi-Fi hotspot on my phone and connecting my MacBook to it. The server software and client app could then see each other and performance was really good and games highly playable. This configuration delivered the best results of all the tests performed.

Just note that in the TrinusVR server settings, on the Main tab, there is an option called “Capture mode”. For most games the best results are achieved by setting this to “Fast”, except for Minecraft that only works when this is set to “Compatibility Mode”.

TrinusVR sells for $9.99 on the respective App Stores (Apple App store and Google Play Store), but as mentioned earlier trial versions are available and the server software can be downloaded for free from the company website.

KinoVR

KinoVR does claim to support USB tethering in iOS, however in practice the results were far from perfect. The client app continuously disconnects from the server software every 15 seconds or so and then takes approximately 5 seconds to reconnect, thus rendering this feature unusable.

When connecting the phone to my MacBook via my home Wi-Fi network the performance was good, even with a good level of graphic details configured in the games.

KinoVR is however found lacking from a user interface and ease of use perspective.

KinoVR Pro sells for $9.99 on the respective App Stores (Apple App store and Google Play Store), and once again there is a free trail version. The server software is freely available here.

IntugameVR

Of all the VR streaming software I tested, IntugameVR is the only one I could not get to work properly. It does not support USB tethering in iOS so once again I configured it to connect over Wi-Fi. Irrelevant of what setting configuration I used the image rendered to the phone display was distorted and squashed. I cannot comment on the performance of this product, as I just could not get it working in any way that was even remotely usable.

IntugameVR Premium is also available on the respective App Stores (Apple App store and Google Play Store) for $9.99 with a free trial version also available. The server software is once again available for free from here.

So given all this, what were my findings? And would I recommend this as a low-cost VR solution?

Well, as long as you do not expect an experience on par with the Oculus Rift or HTC Vibe, you might be pleasantly surprised. Given the low cost of giving this a try, assuming that you have either an iPhone or Android smartphone and utilize the trial versions of the software products mentioned, the cost of this experience will add up to $10 for a Google cardboard compatible headset. Although I would recommend splashing out and getting a plastic headset with padding and better head straps, which you should still be able to pick up for under $20. This will greatly improve the experience from a comfort and usability perspective.

Many people have not had the opportunity to try a premium VR product, such as the Oculus Rift, HTC Vibe or PlaystationVR, and this solution is a great deal more accessible and affordable.

So my recommendation is to give it a try. Who knows it might even convince you to invest in one of the premium VR products available at the moment.

Watch out for DIY VR Part 2, which will be coming soon. In Part 2 I will show how to construct a custom-built VR headset, but in the meantime a few other posts are lined up for your reading pleasure.

DIY VR – Part 1