Weekly Updates

Week 4: Intervention Hardware Planning

The project was broken into two parts: beacon and cane, corresponding to the sensing and intervention aspects of cyber-physical space. And work was distributed between the two partners;one working on the communication and positioning while other on the cane and sensor development.Even on the cane side, it still requires some sensing in order to issue intuitive feedback.

The minimal requirement for sensing is the following:

• - one-bit information for detecting the arrival of the vehicle
• - knowledge of cardinal direction
• - knowledge of the direction to which a user is moving or facing

The minimal requirement for intervening is,

• - one-bit feedback to notify the user that the vehicle is approaching
• - the cane gives the user a signal from which the user knows in which direction he should approach the vehicle

After some research, the following solution is proposed here:

• - the arrival of the vehicle will be detected by the user, since the infrastructure of localization is on the user and can be extended easily; the cane will have a BLE receiver for receiving a notification from the user
• - a 9-DOF sensor will be used to extract cardinal direction and to track the motion and orientation of the cane
• - an algorithm will be developed to extract the relative location and orientation of the vehicle with respect to the user; such relative position will be fed back to the user in real time

Corresponding to the above solution, the following hardware request is in place:

• - Beaglebone black board for real time centralized data processing (include BLE radio)
• - Adafruit 9-DOF absolute orientation IMU Fusion breakout that works with BB
• - A servo or step motor (need some robotics consulting) for the feedback; the idea is that after the relative position is extracted, an arm will be pointing along such direction (the servo motor has feedback mechanism to know how much it has rotated and I think it will be helpful)
• - A vibration motor and disk for the one-bit feedback with potential for modulation to carry more information
• - 3D printed fixture for housing the motor, the pointing arm, and the vibration button

Week 5: Finalisation for the controller platform for the Decawave.

Two way ranging for UWB radio was studied,algorithm for the ranging determined and Arduino selected as controller for the Decawave radios.

Week 6: Implementation of BLE based positioning and Cardinal Orientation extraction

• Implementation of Proximity based location inference using BLEs
• Integrating the BLEs with Raspberry Pi with BlueZ

Week 7: Testing of two way ranging for UWB & Motion orientation extraction.

• Preliminary tests for connectivity and basic sender and receiver functionalities achieved with UWB radios;proceeding to DW1000 based ranging.
• Motion orientation extraction from 9DOF unit on BeagleBone

Week 8: Two way ranging for UWB (arduino + Pi) - Part II

• Two way ranging successfully accomplished
• There were many issues that were encountered;so we focussed on this the entire week debugging and getting the two ranging to work with precision of +/-30 cm

Week 9: IMU study and UWB debug

Week 10: UWB debug and integration of the positioning subsystem with the alignment subsystem

Finals week: Continued with integration further with the cane and home testing

Finals week after: Continued integration and field testing