viSparsh Intro

viSparsh Experience at TechEd2012

viSparsh Prototype 2

We have finally been able to come up with the 2nd prototype of the belt as shown in the pic. Although, the size of the belt still looks similar to the previous version, we have done some major technical upgradations in the belt. The belt has now more robust power management system with single ON-OFF button and less components. Previous post provides the list of changes in this new prototype.

After making it functionally robust, our next aim is to decrease the size of the belt.

In the next version, we are trying to make a sleek design by considering various possibilities like replacing bigger PandaBoard with small BeagleBone, removing Kinect's plastic casing to use only the required components etc.

One of our main focus at present is to build a sleek design before adding more functionalities.

viSparsh @ TechEd2012

All ready with the second prototype of the belt, we showcased viSparsh at the TechEd2012 held at Bengaluru from 21st to 23rd March 2012.

TechEd is Microsoft's annual event to showcase state of the art technologies. We were given a booth to demonstrate our prototype.

This second prototype of the belt has following upgradations

- Less Bulky due to replacement of twelve 1.2V batteries with single 3 cell LiPo Battery.

- Single switch On-Off belt

- One major component mbed removed by directly running vibration motor through PandaBoard.

- Voltage Cut-off circuit integrated to prevent battery from damaging.

- Better Haptic feedback using the new vibration motors.

It was a fantastic experience demonstrating our project in such a big platform. The project was highly appreciated by the industry experts and others who visited the event.

Better Haptic Feedback using new vibration motors

In our first prototype of the belt, we were using ROB 08449 buzzers (left side of the image) to give haptic feedback to the visually impaired people.

The vibrations produced by them were perpendicular to axes of the belt and thus got significantly reduced as we taped them inside the belt. Therefore, we needed more powerful vibration motors for our purpose.

We have replaced the current motors with Pico Vibe 9mm Vibration Motor- 25mm type (RHS of the image) as it provides vibrations both in X and Y planes.

As could be seen in the pic, they are slightly bigger in size (25mm length and 8.8mm diameter) compared to 3.4 mm length of ROB-08449 motors. However, both operate at 3V and Pico Vibe produces 13,500rpm speed compared to 12000rpm of ROB-08449 buzzers. This is a significant improvement as our output depends on the efficiency of these vibrations. Further, instead of earlier 6 motors, we now have to use only 3 motors in the belt ( one for each zone- left, centre and right).

mbed Removed

We have finally succeeded in removing one major component from the belt. The initial design of the belt had mbed in it. We were using mbed to generate PWM (Pulse width Modulation) to be sent to the actuators (vibration motors in our case). However, we eventually figured out that the same functionalities can be provided by PandaBoard without incurring that extra component cost of mbed.

PandaBoard has on-board GPIO (General Purpose Input Output) pins that can be used to render multiple functionalities. We configured three GPIO pins as output and created three software threads to generate variable-duty PWM. This PWM further actuates the vibration motors to guide the visually impaired in obstacle-detection.

Removal of mbed is a major breakthrough for us as we are continuously working on decreasing the size of the belt to make a sleek wearable design.

viSparsh: A touch of light

We are continuously fine-tuning the belt according to the feedback obtained from various blind organizations. We have been visiting National Association for Blinds(NAB), Delhi and obtained valuable feedback from Mohd. Wasim.


Mohd. Wasim is blind since his birth. He really appreciated the concept of a haptic belt that makes his hands and ear free and gives a broader perception of obstacles in the path. Here is a brief video describing the concept and working of viSparsh-

Test Drive-2: Rigorous Testing

This is the second test drive of viSparsh belt. We prepared an obstacle course in a closed hall and and simulated a special test environment with dummies and different sort of obstacles. The obstacles were of different materials, heights and widths. The test results were quite encouraging.


There has been some significant changes from our last test drive- 
1. We have increased number of vibrators from three to six to give a better indication of obstacle to the user. 
2. An autorun script has been created and deployed which starts the viSparsh belt automatically when we switch it on.  


Here is a video snippet of this test drive-

Autorun

Although we finished the first phase of viSparsh. There were certain fine tunings required to make the belt wearable. The belt stills needed to be started by executing a file on ubuntu-terminal. To resolve that we needed an autorun file which automatically runs at startup and kickstarts the belt. This can be done by creating an initialization daemon. We have created this daemon and now the belt can run on its own. The detailed process is given below- 

STEP1: Create the autorun script

Create a new file 'auto_visparsh' at Desktop with the commands starting the viSparsh belt as content. Copy following command in this file. 

COMMAND:

cd /root/OpenNI/Platform/Linux-x86/Bin/Release
./SimpleRead.net.exe 

STEP2: Copy this autorun file to /etc/init.d 

/etc/init.d contains all scripts which are run on startup and shutdown automatically. The '.d' in 'init.d' represents 'daemon'. Daemon are the processes which are executed in background.

COMMAND:

cd /etc/init.d
cp /home/visparsh/Desktop/auto_visparsh /etc/init.d

STEP3: Choose the run-level

Create a 'soft-link' of the autorun file in one of the run-level directory {rc0.d, rc1.d rc2.d rc3.d rc4.d, rc5.d, rc6.d}. For our purpose choose 'rc2.d'. Don't use 'rc0','rc1' and 'rc6' they contain shutdown scripts. We can also set priority of the process using 'SXX' where XX represents the priority {00<=XX<=99}. The letter 'S' represents 'Start' and can be replaced by 'K' to deactivate a script.   

COMMAND:

cd /etc/rc2.d
ln -s ../init.d/auto_visparsh S99auto_visparsh

STEP4: Restart

Now restart the board. This time belt will start automatically.

Test Drive-1: GET, SET……… GO!!!!!!!!!!

After the hard work of one and a half month finally we finished first phase of our project. We have designed the viSparsh v1.0. The belt includes a plastic box which contains PandaBoard, Mbed and Voltage Convertor and the Kinect fixed at the front of the belt. Currently we are using three vibration motors on three sides which we plan to increase to six in version 1.1.

We had our test drive today in our hostel and it worked exceptionally well with no false alarm. Some of the other fellows helped us in shooting the video and becoming the obstacles. Here is the video for this test drive-

Getting ready to release the 1st version

Huhuuu! After facing lots of troubles at every step, we were finally able to get the project working by seamlessly integrating all the components. The video above shows as to how Kinect is able to detect an object (human in our case) and give an alarm depending on the distance between the human and Kinect. In our case, we have used three vibration motors for producing these alert signals. Each motor is used to send an alert for obstacle in one particular direction namely, left, right or middle. These three motors would help a visually impaired person in identifying the direction in which the obstacle is present. We hope to transfer this functionality on the belt in a day or two.This would mark the end of first phase of our project where we were supposed to make a working prototype of the viSparsh Belt.

Active USB Hub: The way out for our Kinect Detection Problem

To our utter surprise, Kinect stopped working all of a sudden. On running Kinect sample programs, it was not able to detect the device as mentioned in one of our previous posts. However few days back, we were able to find the solution for this. After trying all possible combinations like the software error possibilities etc., we were finally left with trying out the Active USB Hub option. And Hurray!, it actually worked. The problem was that although Kinect runs on a 12V adapter , it still draws ample amount of current from the USB port to which it is connected. Thus, while connecting Kinect to BeagleBoard/PandaBoard, Kinect was not able to draw to draw sufficient amount of current from the board. Thus, on connecting Kinect through the Active USB Hub instead of the board directly, we were able to remove Kinect detection problem.

PandaBoard- All thanks to Texas Instruments

Yes!!! Now we have with us the power of PandaBoard and all thanks to Texas Instruments for providing us the board for our project and guess what..it's sponsored by them.

After half an hour long conference with Vikas Joshi representing TI, he sent to us PandaBoard which will give a special edge to our project. We have already installed Ubuntu OS image on it and we are heading towards our next step to complete Phase I of the project.

Thank You Texas Instruments!!!

A new ray of hope amidst Diwali festivities

Huh! After days of searching for the PandaBoard, we finally have found a ray of hope. As mentioned in the previous post we had planned to buy PandaBoard for the project. However, non-availability of it in the market gave us a setback. In order to meet the deadlines we had to start our project with BeagleBoard till the time we found a PandaBoard for our project. We were sure that the unmatched feature set and ease of usage of the PandaBoard would help us in developing a good product quickly. Due to these reasons we kept searching for all the possibilities of getting a chance to work on the PandaBoard. Hurray! We finally have got a new hope from Texas Instruments who have given a positive signal for lending a PandaBoard to us atleast till the end of our ELM. We are excited to try our hands on the same. We wish Diwali brings good news from across the corners for you all too. Happy Diwali Guys and Gals :-) .

Down to the basics

Next, we succesfully tested serial transmission and reception from mbed(through 9th & 10th serial port pins). 

For testing data transmission, we made use of ebox (as we didn't had PC) that was already available with us. To convert the voltages( ttl to RS-232), we had to make use of MAX 232. The circuit looked as follows:

It must be noted that the PCB shown in the diagram on the right is used only for the usage of MAX232 IC in that circuit(since we didn't have spare IC).

Parallel Action on mbed

While other stuff was being done, we registered mbed online and started exploring it using its online available compiler. We tried simple LED programs and PWM and they worked without any problem.

What's in the name ...

After considering various options we had earlier come out with 'viSparsh' as the name of our project. This word has been coined by our team. It is a conglomeration of two words namely vision (Vis) & Touch (Sparsh). We felt the name ViSparsh truly depicted the purpose of our project which was to aid the visually impaired people through the sense of Touch. We also thought this as an apt name for our team too whereby the same word would signify our team's aim of touching the lives of several people through our vision. 

Since we have also built a small lab for the first time at YIF we thought of giving it a name too. One of our fellows (Mr. Balaji) helped us in searching a name and we all finally agreed on 'e-Capsule Lab' as the name of our laboratory. The reason for this were manifolds. Firstly, the size of the lab was that of a capsule. Secondly, 'e' would signify electronics in the word 'e-capsule'. Thirdly, we aim to make electronic solutions for the society with the same aim as capsules are made in the medicine field for the betterment of mankind. Thus, we thought this name to be apt for our lab. We hope that future students of YIF would carry forward the name and build great solutions under this lab that would help our society in path-breaking ways.

The Road Ahead

Some of the other things that we also have started working on are follows:

- We are exploring the options for connecting Internet to the BeagleBoard. Since it doesn't have an inbuilt WiFi, we have decided to go with LAN connection at present. However, since router is placed at some distance, we have to make 20m length cable for our usage.

- For a day or two, we are testing various OS platforms to search the best option suiting our requirements. We have already successfully tested on Angstrom which worked perfectly fine. Our next targets are of Ubuntu Maverick and Android which we hopefully aim to finish soon.

- We have started exploring Kinect to test its various parts. We even did Kinect tear-down in order to gain better understanding of the product.

Slight modification in components

As mentioned in our previous blog, we had initially planned of buying PandaBoard considering the project's future advancements to make use of WiFi/Bluetooth and other upgraded hardware configuration requirements However, things never work as planned :-( and so was the case with us. There was no PandaBoard availability in India before 15th Nov. '11. Our time was passing by swiftly and surely we could not afford to wait so long. In order to keep our deadlines we had to resort to buying 1 BeagleBoard instantly for the initial work while waiting for the PandaBoard's availibility.

Requirement to change the Monitor

We had initially bought Benq 18.5" TFT (LED) Monitor which had only VGA port. However, when Beagleboard arrived we figured out that it would not be a feasible idea to convert HDMI to VGA (Beagleboard-xm had HDMI connectivity while our Benq monitor supported VGA). Fortunately, the vendor agreed to replace the Benq Monitor with Samsung LCD monitor which supported both DVI-D and VGA. In order to use BeagleBoard with this new monitor we simply had to use a HDMI-DVI-D converter. We even checked XBOX360 connectivity with the Monitor and it worked perfectly fine. Thus, finally we found the appropriate monitor for the project.