A novel neuromorphic micro robotic neural probe

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MAE 589M Final Project
A novel neuromorphic micro robotic neural
probe Riley Zeller-Townson Haibo Zhao

Date 12/09/2008
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Project Overview

• Preformed literature Review
• Found gap in current technology
• Proposed design
• Proposed fabrication method for design

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Background

• Many applications for reading neuron voltages
  (neuroprosthetics, stimulation)?
• Neurons pass electrochemical signals to each
  other
• Neurons connect using long, skinny extensions
  (axons and dendrites)?

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History Lesson

• Need to be able to monitor minute electric,
  chemical signals
• First experiments on squid giant axon (Cole,
  Hodgkin)?
• First real microelectrodes hollow glass tubes
• Teflon coated microwires
• Michigan Probes, Utah Arrays, SOI

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Current Work

• Biocompatibility
• Surface coating
• Flexibility
• Probe geometry
• Microfluidics
• Deliver and sample
• Signal quality

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Problem Definition

• No design that physically resembles a neuron,
  though geometry a component of biocompatibility
• Electrodes should be placed like synapses on
  neuron
• Should be able to release chemical signals
  (contain microfluidic channels)?

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• Electrodes/ microfluidics on arms (dendrites)?
• Arms can 'grow' into surrounding tissue
• Arms stored between concentric cyllinders

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How it works

• Inner shaft acts as water main for all
  microfluidic channels, connects to each arm
• Drive actuators feed arms in and out
• Arms bend and rotate around inner shaft

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Shuffle Drive Actuator
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Actuator Dynamics

• EI (d4v(x))/(dx4) S(d2v(x)/dx2) 0
• v Fel3 (1 cosh(k) cosh(Kz) zKsinh(K)
  cosh(K(z-1)))/(EI 2 K3sinh(K))?
• d 2 ?01 v(1(dv/dx)2)dx -2l
• y Fel3 /24EI (3 1/2K-tanh(1/2K)/(1/2K)3 )?

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Actuator Dynamics, cont

• Fe ½ CV2 /d
• Voltage Q/A(d1/e1 d2/e2 d3/e3)?
• Capacitance Q/V A/(d1/e1 d2/e2 d3/e3)?
• Capacitance e0A/d2
• d (1/2 to 3/5) e0A ½ V2 /d2 l3/(24EI) (3 (
  1/2K-tanh(1/2K))/(1/2K)3 )?

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Fabrication Process
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Fabrication Process Continued
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Fabrication Process Continued
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Fabrication Process Continued
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Fabrication Process Continued
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Fabrication Process Continued
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Fabrication Process Continued
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Fabrication Process Continued
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Fabrication Process Finished
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Conclusions

• Completed design that should incorporate several
  biocompatibility techniques
• Created fabrication process for sophisticated
  probe design
• More modeling necessary
• Some more specific dimensions

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Thank you for your timeAny questions?