Characterizing Angular Position in Parallel to Linear Actuation

Dennis Sohn and Elizabeth Lee

ObjectiveTo characterize motor step position with angular position of the

medical capsule robot

Utilize LabVIEW to acquire data from an accelerometer, which will be attached to the base bellow attachment piece of probe

Utilize LabVIEW to linearly control gear shaft, which will vary actuation levels of the probe

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EquipmentLaptop with LabVIEW installed

National Instruments USB 6221 DAQ Board

ADXL330 3-axis MEMS Accelerometer

Protek 32023L Power Supply

Actuation Motor

Medical Probe

Big Easy Driver: stepper motor driver board

Casing

3.5 V Transistor

Bread Board

Fig. 1 Big Easy Driver

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Experimental SetupMain LabVIEW program with two subVIs

First subVI acquire data from accelerometer

Second subVI controls actuation motor

Gear shaft is attached to syringe to transfer rotational motion from motor to linear translational motion to control air pressure via syringe

Accelerometer is attached at base bellow connection piece and acquire data at various actuation processes

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Design

Fig. 2 (a)Medical capsule (above) and (b)setup (right) 5

Design Diagram

Fig. 3 Design setup of medical capsule

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Video of design setup

VR View of Medical Capsule Setuphttps://photosynth.net/preview/view/9953a19e-5735-4058-9885-b438dbc70043?startat=0

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LabVIEW Block Diagram of Main VI

Fig. 4 Block diagram of main VI 8

LabVIEW Front Panel of Main VI

Fig. 5 Front Panel of Main VI 9

LabVIEW Block Diagram of Motor Stepper

Fig. 6 Block Diagram of Motor Stepper 10

LabVIEW Front Panel of Motor Stepper

Fig. 7 Front Panel of Motor Stepper 11

LabVIEW Block Diagram of Accelerometer

Fig. 8 Block Diagram of Accelerometer 12

LabVIEW Front Panel of Accelerometer

Fig. 9 Front Panel of Accelerometer

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Equations for Finding AnglesTilt Angle (Eq. 1):

Panoramic Angle (Eq. 2):

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Graph: Tilt Angle by Motor 1

Fig. 10 Tilt angle of Motor 1, https://youtu.be/grpivihrwbU

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Graph: Tilt Angle by Motor 2

Fig. 11 Tilt angle of Motor 2

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Graph: Tilt Angle by Motor 3

Fig. 12 Tilt angle of Motor 3

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Graph: 360 Degrees Rotation of Capsule

Fig. 13 Full rotation of capsule

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Videos of 360 deg. rotation

19Bottom-view and side-view of medical capsule

ConclusionsStated Objective: to characterize motor step position with angular

position of the medical capsule robotSuccessfully obtained tilt and panoramic angles and control medical capsule in all

positions

Challenges Faced:Calibration of syringes

Inconsistent power supply led to constant calibration of accelerometer

Future Development:To avoid algorithms, input joystick/hand-held controller

Platform to add universal instruments (ie, camera, biopsy mechanisms)

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Summary and Real Life Application:

Potential universal medical applications

Low cost alternative

Reach and screen patients in low socioeconomic population

Detect early signs of illnesses

SAVE LIVES AND DO GOOD!!!

Closing Thoughts

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Who Wants To Try It Out?

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