Inter_Haptics

This project basically tries to implement a system wherein things that appear in Virtual reality devices like Hololens,Occulus etc can be felt . It revolves around adding tactile perception to virtual reality by using Ultrasonic transducers.By manipulating their phase and amplitude it is possible to create a pressure point in space which can be felt by human hands and hence the space can be scanned pretty much like a CRT scanning the TV screen to simulate texture ,shape etc. Please visit 1sand0s.github.io for detailed documentation of the project.

Usage

1.Clone the repository

2.Make sure the system variable "JAVA_HOME" has been set up and pointing to the jdk installation dirctory

3.Navigate to the Inter_Haptics/IS_UltraSonic directory and run

./gradlew cleanEclipse eclipse

The above code will clean the project

4.To build the project ,run

  ./gradlew build

5.To run the project , run

./gradlew run

6.For more details, see my video https://youtu.be/iWZdgHCAuVU

NOTE

Due to the inability of the arduino to switch the signal control transistors at a speed higher than a few milliseconds I resorted to use the Raspberry Pi instead. This adds an extra PNP transistor since GPIO's are 3.3 V operational and not 5V therefore added the PNP as a buffer incase anything shoud go wrong which is very unlikely since the source of the signals are digital as well. This requires wiringPi by Gordon Henderson to be installed on the Raspberry Pi, a brief reveiw will reveal that GPIO's can switch at speeds between 4.1MHz-4.6MHz when operated with wiringPi C library which clocks in the nanosecond range which is perfect for switching the transistors.

Link to wiringPi download and install : http://wiringpi.com/download-and-install/

Link to benchmarking RPi GPIO speed : http://codeandlife.com/2012/07/03/benchmarking-raspberry-pi-gpio-speed/

The pitest file uses 9 Transducers, right now it works only for 9 but with inclusion of Adafruit's PWM i2c driver this can be increased significantly to include as many as 992 transducers.

The pin configs are as follows:

                                  (38)(07)(22)                   (28)(07)(06)
                                  (18)(16)(15)                   (05)(04)(03)
                                  (13)(12)(11)                   (02)(01)(00)
                                      SET-A                         SET-B

Where the numbers of SET-A correspond to the physical pins of RPi's GPIOs and numbers of SET-B correspond to the wiringpi definition or numbering for those physical pins , either one can be used while coding the C file, but strictly adhere to the physical pin mapping (SET-A) when connecting the transducers to the RPI.

Components Required

1. AT89C51/AT89S51 - 1 http://www.keil.com/dd/docs/datashts/atmel/at89c51_ds.pdf

2. 24 Mhz Crystal - 1

3. 30pF Capacitor - 2

4. IC-74573 - 2 http://www.nxp.com/documents/data_sheet/74HC_HCT573.pdf

5. 10k Resistor - 16

6. 20k Resistor - 16

7. 2STL1360 - 64 http://www.st.com/web/en/resource/technical/document/datasheet/CD00072383.pdf

   OR

   PN2222A - 64 https://www.fairchildsemi.com/datasheets/PN/PN2222A.pdf

8. MA40S4S - 64 http://www.farnell.com/datasheets/484560.pdf

9. Atmega328 - 1 http://www.farnell.com/datasheets/1693866.pdf

10. PCA9685 - 2 http://www.adafruit.com/datasheets/PCA9685.pdf

11. IC-AD633JN - 1 http://www.analog.com/media/en/technical-documentation/data-sheets/AD633.pdf

12. IC 7490 - 2 http://www.ti.com/lit/ds/symlink/sn74ls90.pdf

13. IC NE565 - 2 http://www.bucek.name/pdf/ne565.pdf

14. CP2102 - 1 https://www.silabs.com/Support%20Documents/TechnicalDocs/CP2102-9.pdf

15. 1k Resistor - 10

Circuit

1. The link to the PCB layout and schematic on my PCBweb account of the 8051 Signal generator is http://www.pcbweb.com/projects/tzcshXaWRVyupbADNmpTBtbRMHqndq

Queries

For any questions,bugs and any other doubts mail me at 1sand0sardpi@gmail.com