WEEK 16: Project is done​!

The final stage of our experiment:

  • The web application is ready

Screen Shot 2018-12-03 at 4.48.42 PM

  • The path-finding algorithm is working

Screen Shot 2018-12-03 at 4.49.01 PM

  • There are nine clients represent nine nodes in the path.

Screen Shot 2018-12-03 at 4.48.09 PM

  • Three raspberry pis are configured
  • Relays, magnetic sensors are connected to raspberry pis


Demo Recording:


Learning Outcomes:

  1. Software implementation
  2. Hardware implementation
  3. Integration between software and hardware
  4. Beyond technology: Better understanding of assistive technology


  1. The web server was not working as expected
  2. During the final stage of our demo recording, the transmitter was not working when connected through the relay.
  3. The magnetic sensor was not working continuously.

Demo Video:


Feedbacks from Classmates:


1.   Interesting idea using vacuum robot

2.   Successfully manage domain system

3.   The system could have great potential

4.   Should public this research

5.   Expected i-robot behavior shows (wandering around)

6.   good analysis of the limitation

7.   good focus on people, not only technology

8.  good visual aid, demo, ppt, good explaining on the agile model, clear presentation 


1.   How to determine where is A, B, C stations at

2.   If robot wander around finding signals, can you still say it is the shortest distance

3.   What if Roomba wandering so long failing to find the signal

4.   Pace adjustment based on users’ need

5.   How user interact with robot

Week 14: First Stage Done!

What has been achieved:

We had much progress in the past two weeks. We are able to control the power of the transmitter through the raspberry pi by using python code. We set up two sets of raspberry pi, relay, and transmitter.


We are also using magnetic sensors to identify when the robot is docked.



The followings are the links to the video demonstration of the successful control of the magnetic sensor by using raspberry pi and relay.




The code we use:

import RPi.GPIO as gpio


hallpin = 2
ledpin = 3

gpio.setup( hallpin, gpio.IN)
gpio.setup(ledpin, gpio.OUT)
gpio.output(ledpin, False)

while True:
if(gpio.input(hallpin) == False):
gpio.output(ledpin, True)
print(“magnet detected”)
gpio.output(ledpin, False)
print(“magnetic not detected”)

What still needs to be done:

We are planning to build a web server to control multiple raspberry pi by using Javascript nodejs.


Meeting with Dr. Min:

Our group met with Dr. Min on Monday, November 19th. We updated the progress we made and also talked about our concerns. He provides us with another transmitter that we need for the experiment. We really appreciate Dr. Min’s support and mentoring.

Week 12: First Stage Experiment Update

On Thursday, November 1st, after we received all the parts we need for the experiment, our group starts to test and design the experiment. We made significant progress.

We connected relay, raspberry pi, and transmitter. We also implemented a simple code to turn on and off transmitter with raspberry pi.


  1. Make relay control transmitter work. Raspberry pi controls relay turn on / off 1 sec each.
  2. Code:

import RPi.GPIO as GPIO

import time

channel = 21

# GPIO setup


GPIO.setup(channel, GPIO.OUT)

def transmitter_on(pin):

   GPIO.output(pin, GPIO.HIGH)  # Turn motor on

def transmitter_off(pin):

   GPIO.output(pin, GPIO.LOW)  # Turn motor off

if __name__ == ‘__main__’:







   except KeyboardInterrupt:





What we still need:

  1. Research – programming w/ iRobot
    1. Sending infrared signal back to the server, the server turns on the transmitter 1 UNTIL the robot docks at the transmitter 1. Once robot docks at t1, t1 turns off, t2 turns on immediately.
      1. The only problem is, how to program the robot so it can leave t1 immediately after arriving it.
    2. How to monitor the robot when it DOCKED
  2. Further – connect several raspberry pis with servers
  3. Further –  programming real-time automatic transmitter turn on and off
    1. Web server

Week 11: Initial Experiment Update

Team Members: Daeun, Shulin, and Yaqin

We received the parts we order from Amazon last week. We found out the male ones do not match with the transmitter. Because the transmitter requires a larger jack socket. UNADJUSTEDNONRAW_thumb_330f


We ordered another kind of connectors, and they seem not working either. We will meet with Dr. Min next Monday and figure out the solution.

There are a few assignments that are distributed to three of us:

  1. Python programs that calculate the best route from the starting point to the destination –Daeun
  2. The connection between the raspberry pi and the robot — Yaqin
  3. Identify whether the robot is near certain transmitter — Shulin

We have an ideal map for the initial experiment, which will be conducted at Korean Square. The ideal map shows the path of the robot we are trying to achieve, from Yaqin’s office to the conference room.

Screen Shot 2018-10-26 at 11.46.12 AM

Week 7 Proposal Report Done!

We had our weekly meeting on Monday, and we finished our proposal report.

We got some equipment from Dr. Min on Tuesday: an iRobot, several raspberry-pis, and transmitters. We will start the first stage of the experiment after the fall break.

We are not sure about the connection between relays and the transmitters. So, we will do some research over the break, and hopefully, we will have some update soon.

leaves fall colors rainbow
Photo by Pixabay on Pexels.com


Fall 2018 Purdue CNIT581-ATR Project: Indoor Assistive Navigation System

Purdue Fall 2018 CNIT 581— Introduction to Assistive Technology and Robotics

Team Members: Daeun Yim, Shulin Li, & Yaqin Wang

Week Date Project Task
Week 1 August 20th
Week 2 August 27th
Week 3 September 3rd
Week 4 September 10th Form the group
Week 5 September 17th Discuss proposal topic
Week 6 September 24th Proposal Presentation/Blog Setup
Week 7 October 1st Proposal Repordue due October 4th
Week 9 October 8th Prepare Equipment
Week 10 October 15th Initial Experiment
Week 11 October 22nd
Week 12 October 29th Data Collection and Analysis
Week 13 November 5th
Week 14 November 12th
Week 15 November 19th Final Report Draft
Week 16 November 26th
Week 17 December 3rd Final Presentation
Week 18 December 10th Final Report due December 9th