AIM Systems User Guide

Table of Contents

Test Protocol (General)

 Device Power ON

Press the push button to activate the device. System initializes with a quick white pulse. Once done, the sensor turns green, indicating readiness. Keep the sensor still for optimal results.

 Device Power OFF

Press and hold the push button. After 3 secs, the status LED will light up in solid amber. Keep holding for about 1 second until the amber LED goes off. The sensor is now powered down.

  Precautions

    • Mandatory use of Markers to indicate the START and STOP of each trial
    • The number of Markers must be always even
    • Accurate placement of markers is essential for the correct function of the ML model. Markers should be placed 2-3 seconds before the device is picked up (to start the trial) and placed again 2-3 seconds after the device is placed back on the table. Allow for a second or 2 of pause between the end of a trial and the start of a new one.

Spoon Test (AIM-S)

Test description

Equipment

AIM-S, non-slip mat, small ceramic bowl, 125 ml (half a cup of oats), table and chair (if required).

Figure 1: AIM-S Equipment and Test set-up [3].

Test set-up:

Place a bowl with 125 ml (1/2 a metric cup) of dry oats on a non-slip mat. Position the AIM-S next to the participant’s dominant hand. Participants should sit comfortably with back and feet support. Sit at a table about 30 cm from the bowl. If needed, stay in a wheelchair, ensuring legs fit under the table. Use the dominant hand to pick up a spoon, scoop oats, move them towards the mouth without eating, then return spoon and oats to the bowl. Complete five repetitions. Demonstrate the task first for participant familiarization.

Test instructions/Protocol

1. Setup Bluetooth connection and Select “BioKin” App on a Mobile Phone/ Tablet (Follow [Connecting Devices to Your Phone]).

2. After creating a patient ID for a new patient by following [Create a new patient] ), please follow [Conduct a test].

3. Instruct the patient with the following text:

🗣️ This is a test to assess your handling of the spoon, I will be recording your motion from the spoon. You will be asked to pick up the BioKin™ placed on a non-slip mat to the right (or left) dependent on your dominance, of a cereal bowl, use the spoon to retrieve oats as though to eat, take the spoon with oats as close as possible to your mouth without touching, return the spoon to the bowl, empty the contents of the spoon and return the spoon to the start position. We will then ask you to rest for 3 seconds and then repeat the process a further 4 times. Please try to bring the spoon to your mouth, not tilt your head in order to bring your mouth closer to the spoon. Please pick up the spoon when I say “start”.

4. Apply the marker at the beginning of each trial prior to the participant picking up the device and then at the end when the participant has returned the device to the table and withdrawn their hand, then wait for 2-3 second before commencing the next trial. Apply the marker in the same fashion to indicate the start and stop of each trial. The task consists of 5 trials.

5. Test (4) is performed 5 times (i.e 5 trials) in the same recording with a resting period of around 3 seconds between two trials. Press Stop Test to finish recording after the last Marker.

6. For a correct recording, the number of markers should be twice the number of trials, to indicate the start and stop of each trial. For example, we must use 10 Markers for 5 trials.

Cup Test (AIM-C)

  Precautions

  • Please don’t leave the AIM-C turned ON (i.e., START trial in the App) for more than 5 sec before the start of the test.
  • Please don’t leave the AIM-C turned ON (i.e., START trial in the App) for more than 5 sec after the end of five cycles
  • Please provide a marker before the start of a trial and another, after the end of each trial. The same rules for adding markers apply to AIM-C and AIM-S (Number of trials allowed: 5, Total number of markers: 10 markers)
  • Currently, the maximum record limit for 5 trials is 3 minutes.

Test description

Equipment

AIM-C, non-slip mat, table and chair if appropriate.

Test set up

The AIM-C is positioned on the non-slip mat approximately 30 cm in front of the participant, in the midline. The participant should grasp the cup in the middle of the device (on the alternate coloured area).

Figure 2: AIM-C Testing Process.

Test Instructions/Protocol

1. Setup Bluetooth connection and Select “BioKin” App on a Mobile Phone/ Tablet (Follow [Connecting Devices to Your Phone]).

2. After creating a patient ID for a new patient by following [Create a new patient] ), please follow [Conduct a test].

3. Instruct patient with the following text:

🗣️ This is a test to assess your handling of the cup, I will be recording your motion from the cup while you’re using it to drink water 5 times and resting it after each time for a few seconds and repeat the task. We will proceed after I say Start”.

4. Apply the marker at the beginning of each trial prior to the participant picking up the device and then at the end when the participant has returned the device to the table and withdrawn their hand, then wait for 2-3 second before commencing the next trial.  Apply the marker in the same fashion to indicate the start and stop of each trial. The task consists of 5 trials.

5. Test (4) is performed 5 times (i.e. 5 trials) in the same recording with a resting period of around 3 seconds between two trials. Press Stop to finish recording after the last Marker.

6. For a correct recording, the number of markers should be twice the number of trials, to indicate the Start and Stop of each trial. For example, we must use 10 Markers for 5 trials.

Pendant Test (AIM-P)

Test description

The Biokin™ sensor is attached to the chest of the subject using a provided elastic strap with sensor orientation X-, Y-, and Z-axis are aligned to Medial-Lateral (ML), Superior-Inferior (SI), and Anterior-Posterior (AP) axis, respectively. Subjects are asked to maintain balance in the natural standing position with feet together and arms beside the body. The IMU sensor collects data for 30 seconds while eyes are open. If required the examiner should stand at the side and close to the participant to maintain safety during the task should the participant lose their balance. A chair should be placed behind (but not touching) the participant during the task.

Equipment

AIM-P, harness, chair

Figure 3: AIM-P Testing Process.

Test Instructions/Protocol

1. Setup Bluetooth connection and Select “BioKin” App on a Mobile Phone/ Tablet (Follow [Connecting Devices to Your Phone]).

2. After creating a patient ID for a new patient by following [Create a new patient] ), please follow [Conduct a test].

3. Instruct patient with the following speech:

🗣️ This is a test to assess your balancing, I will be recording your motion from the sensor on your chest while you’re standing for 30 seconds. We will proceed after I say Start. I will stand close next to you however if at any time you feel unsteady, please let me know. There is a chair behind you if you need to sit down.

4. The trial is started, tell the patient to stand still. The sensor starts to record the patient’s kinematic movements. The clinician observes the performance of the patient and presses the “Marker” at the time the patient is ready for the test. The actual recording counts now the first marker is pressed. After he/she completes the session (maybe less than 30 seconds depending on severity level), press “Marker” to signal end-of-cycle. No need to change to a different marker. For a correct recording, there should be only two markers for a single trial.

Biokin™ App- User Manual

Android App installation instructions

Step 1

   Go to Google Play Store.

Step 2

   Search ‘Biokin/biokin’.

Step 3

   Select ‘BioKin-AIM’.

Step 4

   Click ‘Install’ to install the app.

iOS App installation instructions

Step 1

   Go to App store.

Step 2

   Search ‘Biokin/biokin’.

Step 3

   Select ‘BioKin (Medical)’.

Step 4

   Click ‘Get’ to install the app.

Allow Permissions

Description

For the app to work as expected, certain permissions need to be granted for the app on the device using. In Android devices ‘Location Services’ and ‘Bluetooth Service’ needs to be enabled whereas in iOS devices only ‘Bluetooth Service’ needs to be enabled.

Steps

(a) Enabled Bluetooth in iOS Devices

(b) Enabled Bluetooth in Android Devices

STEP 1

  Open the BioKin app.

STEP 2

  Allow Bluetooth permissions – When trying to connect sensor you will be prompted to allow “Nearby Device” permission, this is the permission for the app to use Bluetooth connectivity. Bluetooth connection status is indicated on the home screen. If Bluetooth is disabled, app notifies the user to enable Bluetooth.

📝 Note

Ensure Bluetooth is enabled. User will not be able to take a test (Home – Take Test) if Bluetooth is disabled.

Home Screen

Clinician Information

In the Home Page, right arrow shows the Clinicians name and the Clinician ID.

Sign out

To Sign Out from the app, select the button at Home screen, and click Logout.

Login

Figure 4: Onboarding Screens.

Description

This section is for the users to login to the system using the clinician ID and password.

Steps

Step 1

 Open the BioKin app. Users will see onboarding screens if they haven’t logged in before (Figure 6)

Step 2

 Swipe left until you see “Let’s get started” and click on that button.

Step 3                

 Enter Clinician ID (You can enter the Clinician ID with or without leading zeros) and password, and click Login.

Step 4

 After logging in, the user will be directed to the Home screen.

Connecting Devices to Your Phone

Description

This section is to show the way how to connect multiple devices to your phone. There are two ways to connect the device to your phone:

While Charging (Testing Only)

If the device is connected to the charger, press the button three times to enter Bluetooth connection mode.

📝 Note

This method is intended for testing purposes only and is not recommended for data collection, as the charging cable restricts movement.

While Not Charging (Recommended for Data Collection)

If the device is not connected to the charger, press the button once to turn the device on, then press the button three times to enter Bluetooth connection mode.

Steps

Step 1                           

 Charge the device fully before use.

Step 2

 Disconnect the charger.

Step 3

 Turn the device on by pressing the button once.

Step 4

 Enter Bluetooth connection mode by pressing the button three times.

Step 5

 Connect the device to your phone by clicking “Sensors” at Home screen and icon  . The app will display a list of available devices. Select the device you wish to connect to, and the connection status will be shown on the following screen:

📝 Note

The app currently supports connecting up to a maximum of two devices simultaneously.

Step 6

 Wait for the battery indicator for the device appear for the device to be fully connected. You can check connected devices by clicking  .

📝 Note

When the device is connected to power, it enters charging mode with limited functionality.

Create a new patient

Description

This section is to register a new patient.

Steps

Step 1

 In home page, select Take Test.

Step 2        

 In the next screen, select .

Step 3                      

 Case 1: The participant is a control

  • Enter the participant’s year of birth and tick the Control box. The Age of Onset for the control is set to zero by default.

Case 2: The participant is a patient with a known Age of Onset

  • Leave both the Control and Unknown boxes unticked. Enter the patient’s year of birth and the Age of Onset value.

Case 3: The participant is a patient with an unknown Age of Onset

  • Leave the Control box unticked, tick the Unknown box, and enter the patient’s year of birth.

Step 4

 The new patient ID will be displayed in a pop-up dialog box.

  Warning
Note down the newly created patient ID. Use this ID for a new patient to conduct a new test (Within “Take Test” option in the main menu). This ID should be retained for any future assessment of the same patient.

Conduct a test

Description

This section describes how to conduct a test for a specific patient.

Steps

Step 1                                  

 In home page, select Take Test.

Step 2

 Enter the Patient ID (You can enter the Patient ID with or without leading zeros)

Step 3

 Select the connected device from the dropdown menu (Follow [Connecting Devices to Your Phone] if devices are not connected) or click and then follow [Connecting Devices to Your Phone].

Step 4

 If the test device is either AIM-C or AIM-S, please ensure you select the correct option for hand dominance (right or left). Note that the default value for this selection is “Right.”

Step 5

 The following details of the patient will be displayed in the next screen. User can verify the patient details here: Patient ID; Year of Birth; Onset of Disease; Test ID – Indicates the ID of the test taken. Test ID of cup – 01, Spoon – 02, Pendant – 03; Longitudinal ID; Test-Retest ID.

📝 Note

If the participant is a control, the “Onset of Disease” field will display “Control.” If the participant’s age of onset is unknown, that field will display “N/A.”

Step 6

 Select Next to go to the Test screen.

Step 7

 Select Start Test to start the recording.

Step 8

 User will be able to monitor movements of the patient in the graph. Traverse through options Accelerometer, Gyroscope and Pressure to monitor different movements.

Step 9

 Select Mark to add an appropriate number of markers. For a correct recording, the number of markers should be twice the number of tests conducted. The time that a marker is added will be indicated in seconds for the user.

📝 Note

User cannot stop the recording unless the correct number of markers are added. The required number of markers for each type of device is as below: Cup: 10 (5 trials), Spoon: 10 (5 trials), Pendent: 2 (1 trial).

Step 10

 Select Stop Test to stop the recording. User can scroll the graph to view the recording.

Step 11

 Select Test Completed & Redo Test to discard the recording and test again if necessary.

Step 12

 After successfully submitting the test, the user will be prompted for optional feedback or comments:

Clicking ‘No,’ will return to the “Take Test” screen while clicking “Yes” will result in the following screen:

In the “Feedback” screen, the user can select the type of feedback and enter comments in the message box.

📝 Note

After completing a test, please allow up to 2 minutes for the results to appear in the report section.

Accessing Patient Reports

Description

This section allows user to view patient reports. Please note that only the clinicians belonging to a clinic can view reports of the patients in the same clinic

Steps

Step 1                 

 In home page, select Check Reports.

Step 2

 Enter the Patient ID of the required patient. Select View Reports.

Step 3

 User will be able to view the patient report with the time stamp presenting in the local time zone.

The user can conveniently view a patient’s report offline, allowing access to vital information even without an active internet connection. Once reconnected to a network use the sync button to update manually sync the database.

Once reconnected to a network, please go back to Home screen, click on , and use the Sync button (as shown the below image) to update manually sync the database.

A detailed of a report will be displayed as the below:

Existing Patient Reports can be viewed by the user at any point in time- without taking a new test or without device connection established.

Provide Feedback

Description

This section allows user to provide feedback related to the following areas:

  • General Inquiries
  • Test – Test related feedback
  • Device – Feedback related to the sensors or the application.
  • Adverse Events

Steps

Step 1                 

 In home page, select Feedback.

Step 2

 Record ID is optional and it will be auto populated if user is redirected to the feedback screen immediately after conducting a test.

Step 3

 Select Subject from the dropdown menu.

Step 4

 Input the content of feedback in Message box and select Send.

📝 Note

Feedback option can also be accessed after performing the test from.

Clinical interpretation of AIM score

AIM output scores

Stability, Timing, Accuracy and Rhythmicity (STAR)

Characterising the movement of subject’s with ataxia in terms of four dimensions (Stability, Timing, Accuracy & Rhythmicity) based on Holmes theory [7].

Stability (S): This relates to stability in the platform (of execution). The platform is the joints and muscles that are relatively fixed and allow the moving body part to execute a task accurately. For example, the task requiring relative stability of the shoulder and elbow flexion and extension for efficient execution. Relative instability results in an increase in unnecessary movements in secondary axes.

Timing (T): When ataxia is present, tasks that have a time constraint are found to have increased latency before the movement begins and the task is executed at a slower speed, because a less direct course is taken. The same features are often apparent even in the absence of time constraints. These features are more apparent when the ataxia is more severe, suggesting that, subconsciously, timing is a neutral trade off to complete the task. In computational terms, we recognised it as the error between the goal against what is achieved, likely to be impacted by the following two:

(i)        Time for the subject to initiate a moment.

(ii)      Time to complete a movement (speed).

Accuracy (A): Conceptually, a task might be completed slowly but follow the most efficient target. Under these circumstances we will consider this to be an “accurate” performance. When a less direct path is followed there is under or over shoot, then the task will be ‘errors’ compared with a control performance (acknowledging that this may also be associated with timing errors). In computational terms, in this study we recognise it as error between the goal/space objectives against what is achieved in a spatial context (static).

Rhythmicity (R): Irregularity in repeated movements.

Score terminologies in Report (BioKin Mobile Application)

Brief Description

Diagnosis_CS

 Based on Cross Sectional (CS) data, Diagnosis (Patient (P)/Control (C))

Severity_CS

 Based on Cross Sectional (CS) data, Severity assessment based on clinical score (mFARS/ SARA)

*Only to be used for Cross Sectional study

Stability (D)

 STAR [1][2] score; Stability based on P/C diagnosis

Timing (D)

 STAR [1][2] score; Timing based on P/C diagnosis

Accuracy (D)

 STAR [1][2] score; Accuracy based on P/C diagnosis

Rhythmicity (D)

 STAR [1][2] score; Rhythmicity based on P/C diagnosis

Stability (S)

 STAR [1][2] score; Stability based on severity assessment

Timing (S)

 STAR [1][2] score; Timing based on severity assessment

Accuracy (S)

 STAR [1][2] score; Accuracy based on severity assessment

Rhythmicity (S)

 STAR [1][2] score; Rhythmicity based on severity assessment

Spasticity (D)

 Diagnosis of presence of spasticity

Table 1: Brief Descriptions of Score Terminologies in a Report Generated in BioKin Mobile Application

Thresholds 

Cup Spoon Pendant
Cross-sectional 0-93 0-93 0-93
Control Thresholds 0-34 0-28.26 0-13.67

Table 2: Summary of Cross-sectional and Control Threshold Ranges for Three Different Devices

AIM-C

Severity Threshold for cross-sectional study: AIM-C upper-limit score for Controls is 34

AIM-S 

Cross-sectional severity: the output of AIM-S model is rescaled to an index of 0-93, and the calculation of this scale is based on the lower-limit and upper-limit of the predicted score obtained for our specific spoon training data.

Severity Threshold for cross-sectional study (severity): Upper-limit score for Control, severity_cs 28.26.

AIM-P 

Cross-sectional severity: The output of AIM-P model is rescaled to an index of 0-93, and the calculation of this scale is based on the lower-limit and upper-limit of the predicted score obtained for our specific pendant training data.

Severity Threshold for cross-sectional study: Upper-limit score for Controls is 13.67.

BioKin™ Firmware/Hardware Manual

Document Outline

This document details the push button functionality and status LED behaviours for the Biokin e- Module sensor.

Status LED Pulse Patterns

Push Button Functionality

Power On/Initialisation

When the power on button is pressed, the status LED pulses white rapidly indicating the sensor is initialising. This typically takes 1-2 seconds.

System Ready/Idle

When initialisation is complete and the sensor is not connected to Bluetooth or WiFi, the sensor is in a ready/idle state, indicated by a slow green pulse.

Bluetooth Pairing

When Bluetooth pairing is initiated (see Push Button Functionality), the status LED pulses blue rapidly, indicating that the user may pair the mobile device with the sensor.

Bluetooth Connected

When the Bluetooth connection is successful and active, this is indicated by a slow blue status LED  pulse.

Test Active

When the user initiates a test, the sensor enters the test active state, indicated by a slow magenta pulse.

File Transferring

When the user stops a test, any remaining data is transferred from the sensor to the mobile device, indicated by a rapid magenta pulse. Typically, all remaining data is transferred 0.5–2 seconds after the test is stopped.

Battery Charging

When the charger is connected and the sensor is charging, the status LED pulses white every 2 seconds.

Battery Charge Complete

When the charger is connected and charging is complete the status LED is solid white.

Battery SOC < 10%

A battery charge percentage of less than 10% is indicated by a slow amber status LED pulse.

Warning:

It is highly recommended to use only the charger that is ISO standards compliant at all times. Using any other charger for the device can lead to unknown failures and degrade the functionality of the sensor.

IMU Self-Test Fail

As part of the initialisation process, the sensor executes an IMU self-test. The self-test may fail for the following reasons:

  • The sensor has not been kept stationary during power on and initialisation
  • The IMU component is faulty

The sensor attempts the self-test a maximum of three times during initialisation. As soon as the self- test passes, initialisation continues. Self-test failures on attempts one and two are indicated by the status LED amber warning pulse. The user may eliminate any unintended movement of the sensor at this time. On the third and final self-test failure, the status LED pulses red and white rapidly and will not complete initialisation. To attempt initialisation again, the sensor must be powered down and on again with the sensor kept stationary.

If the sensor is kept stationary and the self-test repeatedly fails, this indicates an IMU component fault. The sensor is not operational in this state and the user should contact the supplier.

Warning:

The sensor indicates a warning by rapidly pulsing the status LED amber three times. Warnings can be triggered by numerous events and are non-critical. The user may continue with normal operation of the sensor.

Power Down

See Push Button Functionality. When a power down is initiated the status LED shows solid amber. When power down is complete, the status LED turns off.

References for scoring

[1] Krishna, R., Pathirana, P.N., Horne, M., Corben, L. and Szmulewicz, D., 2021. Quantitative assessment of Friedreich Ataxia via self-drinking activity. IEEE Journal of Biomedical and Health Informatics.

[2] Kashyap, B., Phan, D., Pathirana, P.N., Horne, M., Power, L. and Szmulewicz, D., 2020. objective Assessment of cerebellar Ataxia: A comprehensive and Refined Approach. Scientific reports, 10 (1), pp.1-17.

[3] Nguyen, K.D., Corben, L.A., Pathirana, P.N., Horne, M.K., Delatycki, M.B. and Szmulewicz, D.J., 2020. The assessment of upper limb functionality in Friedreich ataxia via self-feeding activity. IEEE Transactions on Neural Systems and Rehabilitation Engineering, 28(4), pp.924-933.

[4] Corben, L.A., Nguyen, K.D., Pathirana, P.N., Horne, M.K., Szmulewicz, D.J., Roberts, M. and Delatycki, M.B., 2021. Developing an Instrumented Measure of Upper Limb Function in Friedreich Ataxia. The Cerebellum, pp.1-9.

[5] Ngo, T., Pathirana, P.N., Horne, M.K., Power, L., Szmulewicz, D.J., Milne, S.C., Corben, L.A., Roberts, M. and Delatycki, M.B., 2020. Balance Deficits due to Cerebellar Ataxia: A Machine Learning and Cloud-Based Approach. IEEE Transactions on Biomedical Engineering, 68(5), pp.1507-1517.

[6] Rummey C, Corben LA, Delatycki MB, et al. . Psychometric properties of the Friedreich Ataxia Rating Scale. Neurol Genet 2019;5:e371. doi: 10.1212/NXG.0000000000000371.

[7] B. Kashyap, D. Phan, P. N. Pathirana, M. Horne, L. Power, and D. Szmulewicz, “Objective assessment of cerebellar ataxia: A comprehensive and refined approach,” Scientific reports, vol. 10, no. 1, p.9493, 2020.