Humble HubbleTeam 18 – Derek Pesyna

AbstractThe proposed project is a self-aiming

telescope. This telescope will obtain its global position and the local time via GPS. It will then automatically orient

itself to point at a user selected target (star) using a variety of onboard sensors.

Background: http://apod.nasa.gov/apod/image/1302/ngc1763_lake_1600.jpg

Block Diagram

Definition of Criticality Levels

• λ - the predicted number of failures per 106 hours of operation • High: Injury to user and critical system failure (

10-9 )• Medium: Whole system needs

replaced/repaired ( 10-6 )• Low: PCB/single component can be easily

repaired ( 10-5 )

Overall Schematic

Sensor Breakout Module

FMECA Chart

Failure No.

Failure Mode Possible Causes Failure Effects Method of Detection

Criticality Remarks

A1 Motor Output @ 100% (full on)

-H-Bridge Failure -Micro motor output stuck high

Telescope moves unexpectedly & continues moving

Observation Medium Worse case: telescope mount breaks

B1 Telescope does NOT point north and is NOT level during calibration

-Compass failure-Accel. Failure-Gyro Failure-Encoder Failure

Compass cannot be calibrated and thus will not function

Observation Low Component replaced on breakout module and/or sensor breakout PCB replaced

B2 Telescope does not point to correct celestial body

-Compass failure-Accel. Failure-Gyro Failure-Encoder Failure

Compass is not functional (manual control may be necessary)

Observation Low

C1 Telescope does not move

-269 Vex Motor Failure-Power supply not functional-Micro fried

Compass not functional

Observation Low/Medium