Integrated System Build & Test
Table of Contents
Team Vision for Integrated System Build & Test PhaseSummarize: What did your team plan to do during this phase?
- Mechanical : Complete subsystem (hand piece, mounting components)
- Software : Modify control logic for multiple axis braking system
- Electrical Rewire circuit and increase its robustness
- Other : Complete 75% of technical paper, other phase specific documentation
- Main goal : Assemble full system
What did your team actually accomplish during this phase?
- Mechanical : Completed hand component, mounting components, assembled mechanical subsystem components
- Software : Tested varied braking threshold parameters, completed tremor state to brake fire map, finished updating control logic, completed qualitative testing
- Electrical : Soldered new solder shield to Arduino, rewired circuit, set up electrical casing, completed testing throughout to make sure everything works properly
- Other : Completed 75% of technical paper and all phase specific documentation
- Main goal : Assembled full system.
Pictures of Assembly and Components
Test Results Summary
Analysis of Varied Control Logic Parameters
Purpose and Plan
Raw data from 9DOF sensor (gyroscope) was collected using drill powered test rig, operating at approximately 6.5 Hz. 4 data types were collected, brakes off, and brakes on with braking threshold set at 50 degrees/second, 75 degrees/second, and 100 degrees/second. Data was collected in triplicate.
Gyroscope data from tremoring axis (X) was converted into displacement using numeric integration and converted from rotational to linear displacement in MATLAB. The height peaks were determined using built in functionality with manual adjustment of threshold values. The script for analysis is included in the appendix.
Our engineering requirements state that in order for the system to be behaving within an acceptable level, the displacement with brakes on should be less than or equal to 75 % of the displacement with brakes off (stretch goal, 50% reduction). We already know that with the threshold set at 75 degrees/second our engineering requirement and stretch goals are met.
The goal of this further analysis is to determine the optimal braking threshold and to better understand how varying this parameter will affect our results quantitatively. It is predicted that a lower threshold will more effectively reduce tremor amplitude, but it may cause restrictions in ease of natural movement.
Based on our testing, all testing thresholds yield acceptable results. A final decision for braking threshold should not be made until further testing (multi axis, ease on natural motion) is completed and analyzed.
Risk and Problem Tracking
Vision for Imagine RIT
Our senior design project a wearable assistive medical device intended to mitigate Essential Tremor. Essential Tremor is a neuropathy that causes involuntary rhythmic muscle contraction which afflicts roughly 7 million Americans. A tremor typically manifests in the arm of the patient, and can progress up the arm and to the neck and voice box as the condition progresses. There are drug treatments that require constant monitoring, dosage adjustments, and can cause some unpleasant side effects. Curative deep brain stimulation procedures are also available, but the procedure is very invasive. Our device provides an alternative inexpensive, noninvasive option. The tremor is sensed with a 9 degree of freedom sensor on the hand. Restrictive braking forces are produced by bearing mounted electromagnetic brakes, which is controlled by a microcontroller operating with active feedback logic. Our team worked on the second iteration of this project. This year, we worked to make the design more robust and complete to improve its mitigation functionality. We are working in parallel with a tremor data acquisition device team, and a device test rig team.
Plans for next phase
By the end of the next phase we plan to have the following completed:
- All testing to verify that engineering requirements are met.
- Completed multi-axis test rig (for testing and Imagine RIT).
- Completed technical paper, poster, and lightning video.
- All hand off and V&V documentation.