P18571: Sunspot Radio Telescope III

Integrated System Build & Test

Table of Contents

1 Team Vision for Integrated System Build & Test Phase
2 Radio Technology Development
3 Software Development
4 Risk and Problem Tracking
5 Functional Demo Materials
6 Plans for next phase

Team Vision for Integrated System Build & Test Phase

A 4 week plan was implemented for the team to work asymmetrically, playing on each team members strengths The full list of deliverables and their statuses can be found here

Radio Technology Development

Rather than rely on the network analyzer measurements, the feedhorn antennae were tested using the dish. In addition to the previous antennas, a new antenna suggested by our guide and a subject matter expert was also tested.

Ideally the sun would have been used as a test source, but it could not be located on the cloudy day. Instead, the dish was pointed at RIT. All antennas saw the same spectrum and picked up the same emitters from RIT. Due to its being easier to mount on the dish and receiving signals slightly better than the other antennas, the planar antenna above was chosen as the new feedhorn.

A replacement was found for the broken RF switch, as the previous design was not available.

The switch is low-loss and is a fitting replacement in terms of the system's radio frequency needs. However, the new switch operates on 3.3 volt logic, while the previous switch (and the Arduino) operate on 5 volt logic. A solution will need to be determined for bringing down the logic inputs from the Arduino, but a resistor divider should be sufficient. The new switch also requires a negative power rail, but tests showed that it operated as desired without a negative supply.

Software Development

Coordinate Translation

The software is capable of using and translating between three coordinate systems:

Equatorial (right ascension/declination) -- commonly used for astronomy
Horizontal (altitude/azimuth) -- used as angle from observer's point of view
Motor positions (rotary/linear actuator pulses) -- tracked positions of motors

Server Software

The server protocol was extended with additional commands to allow clients to enumerate stored errors, list FIT files, schedule night-time observations, and list available night-time targets. Server Protocol v1.2

Automatic FIT file uploads were tested in a simulated environment using the same software as ETH Zurich (vsftpd); actual FIT uploads were tested on site using the actual ETH Zurich server.

The server produces a daily status email reporting the status of key subsystems, the number of FIT files uploaded for the day, and any recorded error messages or warnings.

Server Source v1.0.5

Arduino Source Code

LabVIEW Development

Slav

Risk and Problem Tracking

ID	Category	Risk Item	Effect	Cause	Likelihood	Severity	Importance	Action to Minimize Risk	Owner
R1	Technical	Improper feedhorn installation	Feedhorn may have loose mounting or be unable to be assembled.	Manufacturing Faults	0	3	0	Feedhorn to be replaced with Antenna	ME
R2	Technical	Unreliable internet connection to Zurich	May not be able to transmit all data overnight.	Environmental conditions including thunderstorms.	2	1	2	"Provide data backup until Zurich server confirms reception"	CE
R3	Technical	Dish may be too heavy for motors/actuators	Tracking functionality is lost, manual repairs required	Ice buildup, power depletion	1	2	2	Motors oversized for current load	ME
R4	Technical	File transfer system error	Zurich server receives incomplete data	Power lost or connectivity issues.	0	2	0	Create Temp file on FTP server, move when complete	CE
R5	Technical	Auto-calibration error	Incorrect data analysis, manual repairs required	Drift of control systems over time	1	3	3	2 callistos in parallel, one for cal one one for data	CE
R6	Technical	Network Communication Error	Remote operation made difficult or impossible	Loss of connectivity, internet outage	1	1	1	Ensure system doesnt rely on TeamViewer/Active user input	CE
R7	Technical	UPS battery dies	System loses power and is no longer operational.	Mains power is lost and UPS battery is exhausted.	1	2	2	Put system into safe shutdown state before battery is exhausted	CE
R8	Technical	RadioEyes/LabView incompatibility	Additional time required for integration solution	No documented API support	0	2	0	Plan B In effect:= custom Astronomical Data	ME
R9	Technical	Feedhorn selection may carry unexpected collaterals (integration)	RX levels may become inefficient for extraction from raw signal	Mismatching impedance and frequency response	1	3	3	Perform extensive testing on feed/dish assembly	EE
R10	Technical	Software Error	Data may be corrupted or incorrect; Zurich may not recieve data at all	Improper program setup / unforeseen program error	1	2	2	"Perform extensive software testing and provide data backup"	CE
R11	Technical	Interference between subsystems	May cause errors or discrepencies in subsystem operation	Improper magnetic shielding on power lines near vulnerable systems	1	2	2	"Isolate magnetic interference, or place wiring more carefully"	EE
R12	Technical	Improper power management	One or more subsystems failing due to internal power loss	Power delivery components insufficient to meet power needs	1	3	3	Perform extensive power system calculations	EE
R13	Technical	Internal subsystem overheating	Damage to one or more subsystems	Inadequate cooling systems or lack of temperature sensor	1	3	3	Test Plan for thermal model validation	ME
R14	Technical	UPS overheat	Damage to battery system	Temperature sensitive battery in harsh enviornment	0	3	0	Will install UPS indoors	ME
R15	Resource	Insufficient budget to meet all project requirements	May need to take performance hits to accomodate cheaper budget	Limited funds (~$500)	0	1	0	$1500 donation from ASRAS	All
R16	Resource	Destruction of Suntracker project hardware	Loss of uniquely designed hardware, project delays	Incorrect assumptions about input levels and tolerances/ general clumsiness	1	3	3	Observe best practices, be careful, stay away from other people	All
R17	Resource	Inadequate space to assemble and test	Team may not be able to build project	Specialized Test Requirements	1	3	3	Ensure that proper space or devices are reserved well in advance, only attempt finaly assy onsite. Prelimnary Assembly at RIT observatory. Wind and Thermal Testing	All
R18	Resource	Theft of system components	Irreplaceable components may be lost	Improper storage of materials	1	3	3	Lock physical project materials in a locker/keep at home	All
R19	Resource	Insufficient backup data storage	Zurich or ASRAS server may fail to recieve data	Insufficient or nonexistant backup data storage	0	2	0	Amount of data needed to exceed data capacity exceeds lifetime of system	CE
R20	"Environmental/Social"	Remote log-in to unit may pose security threat	System may be tampered with by unauthorized user	Malicious actor obtaining password/login information	1	3	3	Use Username/Password +Secure Design	CE
R21	Technical	IP66 may not be as advertized	Water Damage	Leak, improper sealing	1	3	3	Test current enclosure, use waterproof sealing	ME
R22	Technical	Software sends too many emails consecutively	Flooded Mailbox	Periodic Failure alerts	2	2	4	Batch alerts together, rate limit messages	CE
R23	Technical	Smarthost service unavailable	System unable to send email alerts	Service is unavailable	1	2	2	Alternate alert mechanism (stacklight)	EE
R24	Technical	Wind Damage	System components break	High winds, low structural integrity	1	3	3	Reinforce structure	ME
R25	Technical	System resonates with wind	System components break	Winds hitting natural frequencies of structure	1	3	3	Apply Damping	ME
R26	Technical	Heat Sensor Fails	System overheats	Random/Software Failure	1	2	2	Overkill on cooling solution/ Software safeguards	ME
R27	Technical	Humidity Sensor Fails	Loss of humidity information, water damage	Random/Software Failure	1	1	1	Enhanced waterproofing solution/ Software safeguards	ME
R28	Technical	Custom Astronomy Coordinate map unfeasible	Unable to build necessary Radio Eyes Functionality ourselves	Scope too large/Too complicated	0	2	0	Top 40 RF list found, on track to be programmed	EE/CE/ME
R29	Technical	Improper Antenna Mount	Impossible to get good reading	Focal point miscalculation/ Design Change	1	3	3	Adjustable Antenna mount	ME
R30	Technical	Runaway Dish	Damage to components	Control/Electrical Failure, various	1	3	3	Install E stops	EE
R31	Technical	Shorts and Interference in unit	System Malfunction, Potential Damage	Improper Wiring	1	3	3	Rewiring, Robustification of system	EE
R32	Technical	Software Communication Error	Hardware may not be controlled by PC software	Software doesn't start, starts incorrectly	1	3	3	Arduino defaults into safe position if no PC contact	CE
R33	Technical	Improper Antenna installation	Antenna may have loose mounting or be unable to be assembled.	Manufacturing Faults	1	2	2	Utilize good practices	ME
R34	Technical	Dropped connection	Lack of remote control	To be investigated	0	3	0	Programmed Ping-Pong procedures, and time outs on both end.	ME/CE
R35	Resource	Defective RF switch	RF subsystem does not function	ESD damage?	0	3	0	Purchase new switch	EE
R36	Resource	Insufficient Funding for Antenna Mount	Antenna cannot be mounted	Unexpected price of RF switch replacement	3	3	9	Simplify Design, use existing hardware, slight overbudget unescapable	ME