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PORTLAND STATE UNIVERSITY Obstacle Recognition System For the Blind Presented by Team 3 Prachi Pai Asnodkar, Padmashree Patil, Sarita L. Tellez Sanchez, Thuy Tran December 13, 2014 Slide 2 PORTLAND STATE UNIVERSITY Overview Problem and Need Statement Value Proposition Objective Alternatives Approach & Schedule Requirements Design Implementation Testing & Results Contributions Lessons Learned 2ECE 411 Practicum Project Slide 3 PORTLAND STATE UNIVERSITY Problem & Need Statement Problem Statement: Without vision it can be challenging for a visually impaired person to navigate through a room or a hallway without bumping into obstacles. Even with aid, such as walking stick, it can be sometimes inconvenient, uncomfortable, and perhaps inaccurate in avoiding obstacles. Need Statement: Develop a device that would assist visually impaired users to sense objects without touching the object or carrying a stick in their hand. ECE 411 Practicum Project3 Slide 4 PORTLAND STATE UNIVERSITY Value Proposition Significant number of visually impaired persons use long white cane or guide dog to identify the obstacles. Our project is aimed at reducing the dependency on white cane and guide dogs. Our solution is: Cheap and affordable Detects both static and moving obstacles Saves the effort of carrying the white cane, saves on the cost of maintaining a guide dog, and more. ECE 411 Practicum Project4 Slide 5 PORTLAND STATE UNIVERSITY Objective Objective: Design and build a working prototype of a system that will help visually impaired person to sense the obstacle in front of them by sending a vibration from the system. Motivation: Our team had an interest to create a device that could aid a visually impaired person as they need an aid that can help them avoid collision with obstacles. This system will help them detect obstacles by sending vibrations. ECE 411 Practicum Project5 Slide 6 PORTLAND STATE UNIVERSITY Alternatives At present following are the primary methods used by visually impaired person to identify and avoid an obstacle: Long white cane: A long white cane is used to extend the users range of touch sensation. It is usually swung in a low sweeping motion across the intended path of travel to detect obstacles. Dog guide: A small number of people employ guide dogs to assist in their mobility. These dogs are trained to navigate around various obstacles. Human guide: A person guides the visually impaired, but this makes them dependent on others assistance. ECE 411 Practicum Project6 Slide 7 PORTLAND STATE UNIVERSITY Approach Step 1: Performed benchmarking to get ideas to help design our project Step 2: Define components and resources required Step 3: Read & perform tutorials to gain knowledge for the required components and resources, such as Atmel Studio and EagleCAD Step 4: The project was divided based on each team members strength Step 5: Communications Timing and organization to complete tasks were formed based on homework deadlines Most of the tasks were completed in group and through proactive communication between the team members ECE 411 Practicum Project7 Slide 8 PORTLAND STATE UNIVERSITY Project Schedule ECE 411 Practicum Project8 Slide 9 PORTLAND STATE UNIVERSITY User Requirements Safe design Accuracy in calculating distance from the object Differing intensities of vibration according to proximity to an object User friendly with ease to use Cost effective Reasonable size for comfort ECE 411 Practicum Project9 Slide 10 PORTLAND STATE UNIVERSITY Technical Requirements Sense objects within at least 1m of range Vibrate when user is as far as 1 meter from an obstacle Have a vibration motor Have an ultrasonic sensor to sense distance Have a microcontroller Fit on two layer PCB Assembled by hand by each member of the group Tested for acceptable working characteristics ECE 411 Practicum Project10 Slide 11 PORTLAND STATE UNIVERSITY Technical Requirements (Contd.) Be designed in EagleCAD Have an LCD that displays the distance values Use a 9V battery as power supply and a voltage regulator to output 5V for the components in the device Operate within an enclosed packaging Be manufactured on a PCB with dimensions of 10x7 cm Have at least a 95% of accuracy in sensing the obstacle at the farthest distance (1 meter) Increase the intensity of the vibration based on the proximity of an obstacle ECE 411 Practicum Project11 Slide 12 PORTLAND STATE UNIVERSITY Design ECE 411 Practicum Project12 Slide 13 PORTLAND STATE UNIVERSITY Top Level Circuit Block Diagram ECE 411 Practicum Project13 There are four main components which provide a separate and distinct functionality towards the overall project, and other two are power supplies Slide 14 PORTLAND STATE UNIVERSITY Component 1: The Ultrasonic Sensor (HC-SR04) ECE 411 Practicum Project14 Detects if the user is in the range of obstacle or not Slide 15 PORTLAND STATE UNIVERSITY Component 2: Atmeg-328P Microprocessor ECE 411 Practicum Project15 The Atmeg-328P is the control unit of the entire device Slide 16 PORTLAND STATE UNIVERSITY Component 3: 310-101 Vibration Motor ECE 411 Practicum Project16 Vibration motor is a button type motor that vibrates when sufficient power is given to it. Slide 17 PORTLAND STATE UNIVERSITY Component 4: LCD (Liquid Crystal Display) ECE 411 Practicum Project17 Displays the distance value at which the user is within an obstacle. The LCD is designed for testing purposes Slide 18 PORTLAND STATE UNIVERSITY Implementation ECE 411 Practicum Project18 Slide 19 PORTLAND STATE UNIVERSITY Schematic ECE 411 Practicum Project19 Slide 20 PORTLAND STATE UNIVERSITY DC Voltage Regulator ECE 411 Practicum Project20 Slide 21 PORTLAND STATE UNIVERSITY Connecting the AVR Programmer ECE 411 Practicum Project21 The AVR programmer is connected to the microcontroller on the PCB via the ISP (In System Programming) connections Slide 22 PORTLAND STATE UNIVERSITY Ultrasonic Sensor ECE 411 Practicum Project22 Connect the Trigger pin and Echo pin of the ultrasonic sensor to two I/O pin of microcontroller Slide 23 PORTLAND STATE UNIVERSITY Vibration Motor ECE 411 Practicum Project23 Slide 24 PORTLAND STATE UNIVERSITY LCD Display ECE 411 Practicum Project24 Slide 25 PORTLAND STATE UNIVERSITY Board Layout ECE 411 Practicum Project25 Top ViewBottom Layer Slide 26 PORTLAND STATE UNIVERSITY N Y Flow chart ECE 411 Practicum Project26 Initialize Obstacle within 1m? Display distance Enable PWM Turn on motor Start Slide 27 PORTLAND STATE UNIVERSITY Design Code ECE 411 Practicum Project27 Slide 28 PORTLAND STATE UNIVERSITY Testing Test 1: Acceptance test for the obstacle recognition system Explanation The system unit must vibrate within 1 meter from an obstacle Action Write program for a LCD to monitor the distance from an obstacle Test the device by having a person wear the device and approach an obstacle Expected Results The LCD should give 90% accurate distance that it is from the user to the obstacle Vibration motor should start vibrating when the person is within 1 meter of an obstacle ECE 411 Practicum Project28 Slide 29 PORTLAND STATE UNIVERSITY Testing Test 2: Integration test case for the Ultrasonic module HC-SR04 with Atmega 328P Explanation The ultrasonic sensor should have 95% accuracy in sensing obstacles as far as 1 meter Action Place an object within 1 meter of the sensor Place an object further than 1 meter of the sensor Expected Results Within 1 meter, LED should turn ON Further than 1 meter, LED should turn OFF ECE 411 Practicum Project29 Slide 30 PORTLAND STATE UNIVERSITY Results Ultrasonic sensor worked accurately Able to observe the behavior we expected when an object was within the 100 cm range Burnt at least 2-3 sensors in the debugging process but our end result was better than expected LCD displayed accurate distance values Methodology of PWM to increase and decrease the voltage on the motor pin worked accurately from what we could observed on the multi-meter. ECE 411 Practicum Project30 Slide 31 PORTLAND STATE UNIVERSITY Results (Contd.) Challenges The motor has a small operating voltage range Soldering Surface Mount components Inexperience with the software needed for project ECE 411 Practicum Project31 Slide 32 PORTLAND STATE UNIVERSITY Contributions Sarita Lead schematic development Lead management of documentation and writing Co-lead homeworks with Padma Co-lead PCB setup with Thuy Co-lead Wiki management with Prachi System Testing and Validation Support Project Idea development support Consolidate final presentation Thuy Lead Board layout development Lead System Testing and Validation Co-lead PCB setup with Sarita Co-Lead Code Testing with Prachi Schematic development support Homework support Project Idea development support Enclosure design Prachi Lead Code Development Lead Project Idea development Co-Lead Code Testing with Thuy Co-lead Wiki management with Sarita System Testing and Validation support Homework support Padma Lead ordering, organization, and management of major components Lead Wiki Setup Co-lead homeworks with Sarita System Testing and Validation Support PCB setup support Project Idea development support Co-lead management of documentation and writing with Sarita ECE 411 Practicum Project32 Our team divided the contributions by assigning leading or co-leading responsibilities along with support roles to each member for various tasks Slide 33 PORTLAND STATE UNIVERSITY Lessons Learnt Time management and working with other team members to split tasks and conquer are very important for success Trust, mutual respect, team efforts is important to successfully accomplish the tasks Project management is as important as solving for the project requirements Project schedule and GNATT chart is a great tool to manage and track work progress Debugging takes a lot of time and requires relying on team members for their expertise, which can result in positive outcomes Collaboration and coordination are key to success ECE 411 Practicum Project33 Slide 34 PORTLAND STATE UNIVERSITY Lessons Learnt (Contd.) Better understanding of synergies of tasks and due dates Better coordination amongst team members for ordering of parts Division of tasks could have been more balanced Need to highlight team expectations at the forming stage of the project ECE 411 Practicum Project34 Slide 35 PORTLAND STATE UNIVERSITY Reference Ultrasonic sensor https://docs.google.com/a/pdx.edu/document/d/1Y-yZnNhMYy7rwhAgyL_pfa39RsB- x2qR4vP8saG73rE/edit http://www.ezdenki.com/ultrasonic.php Atmel http://www.micahcarrick.com/tutorials/avr-microcontroller-tutorial/getting-started.html#section_4 http://www.atmel.com/microsite/atmel_studio6/ Eagle http://tinkerlog.com/howto/mega328-header/ https://learn.sparkfun.com/tutorials/using-eagle-schematic/adding-parts-to-a-schematic LCD http://extremeelectronics.co.in/avr-tutorials/using-lcd-module-with-avrs/ Vibration motor http://www.learningaboutelectronics.com/Datasheets/Precision-Microdrives-Vibration-Motor- Datasheet.pdf ECE 411 Practicum Project35 Slide 36 PORTLAND STATE UNIVERSITY Questions ECE 411 Practicum Project36