Robotic Microphone Stand for Pogo Studio ECE445 Team #28 TA: Lydia Majure Kai Jiang Weihong Yuan

Introduction Our project is a remote-controlled microphone positioning robot with four positional memories. It provides a safer and more convenient solution for microphone positioning.

Features Remote controlled Three dimensional movements Up to six positional memories Low cost

Robotic Microphone Stand Control BoardPCB Mounted on Mic Stand

Robotic Microphone Stand Microphone Stand

System Overview Hardware  Power supply  Motor and motor controlling units  RF modules  Mechanical structure Software  Control and positioning PIC

System Overview H bridges

Hardware Overview Power supply  12V, 6V and 3V power input  5V and 3.3V voltage regulator RF modules  433MHz LR series RF module by Linx Motor and motor controlling units  12V DC gear head motor by Pittman  H-bridges  Mechanical motor encoders Mechanical Structure  Built by ECE machine shop

Power Supply 12V  Rechargeable  35 AH 6V and 3V  AA batteries

Power Supply (Requirements) 30 mV maximum voltage ripple for 3V and 3.3V voltage supply Reasonable battery run-time

Power Supply (Verification) 12V test5V test 3.3V test3V test

Power Supply (Verification)

RF Modules Transmitter  Transmitter  Encoder  Antenna Receiver  Receiver  Decoder  Antenna transmitter encoder decoder receiver

RF Modules (Requirements) 30 mV maximum voltage ripple Operation range: 20m Operation with obstacles in between

RF modules (Verification) 8 inputs and outputs LED indicators Obstacles Antennas added

Motor (Requirements) Enough torque to drive the lead screws Reasonable moving speed No noise while not rotating

Motor (Verification) Torque Calculations Weight conversion 13.28lb= oz motor & screw connection gap = inch screw diameter = 0.52 inch torque required = oz-in gear ratio needed = 21.06:1 Final choice: 127.7:1 gear head 12VDC motor

Motor (Verification) Lead screws: 1 inch/turn Motors (no load): 60 turns/min Result: Moving spead = 60 turns/min * 1 inch/turn = 60 inch/min = 1 in/s = 2.54 cm/s

Mechanical Structure Our designMachine built by ECE machine shop

Software PIC software  Receive control signals from the decoder of the RF module on the microphone stand side  Send corresponding control signals to H-bridges  Store and retrieve motors’ movements

X Movement

XYZ Movement

Store

X Retrieve

Overall

Retrieving Error Analysis PIC miscounting (initializing error) 3/36*1 inch=0.083 inch (0.2116cm) Encoder glitch (unpredictable error) Total max error: 0.11inch(0.28cm)

Successes Remote controlled Three dimensional movements Stable store and retrieve functionality Small retrieving error All requirements are satisfied

Future Hardware Development Install bumper switches for mechanical protection Use optical motor encoders for better precision Remove the 6V power supply Panning functionality Three PICs

Future Software Development Store positions into PIC’s memory Add boundary conditions for better mechanical protection Use three PICs for faster retrieve Computer or tablet interface

Credits Electronic service shop  Mark Smart  Skot Wiedmann Machine shop  Scott Mcdonald  David Switzer TA  Lydia Majure

Thank You