heliostat operators manual

2015

Heliostat 2014-2015

ERAU Senior Design

4/21/2015

Heliostat Operators Manual

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Table of Contents 1. Heliostat Operators Manual Introduction ............................................................................................ 2

2. Hardware Overview .............................................................................................................................. 2

3. Standard Operating Procedure ............................................................................................................. 3

3.1. Accessing the classroom COAS 501 .............................................................................................. 3

3.2. Turn on the Control Computer ..................................................................................................... 3

3.3. Check to make sure power is connected to the power box ......................................................... 3

3.4. Click icon to run the Heliostat ....................................................................................................... 4

3.5. Choose an object to track ............................................................................................................. 4

3.6. Check local weather conditions .................................................................................................... 5

3.7. User Authentication ...................................................................................................................... 5

3.8. Power on “Smart Devices” ............................................................................................................ 6

3.9. Power on Auxiliary Devices ........................................................................................................... 6

3.10. Alignment Procedure ................................................................................................................ 6

3.11. Tracking Procedure ................................................................................................................... 7

3.12. Shutdown Procedure ................................................................................................................ 7

3.13. Power Off Electronics ................................................................................................................ 8

4. Troubleshooting .................................................................................................................................... 8

4.1. The microcontroller shows a red X ............................................................................................... 8

4.2. The LX200 shows a red X............................................................................................................... 9

4.3. The LX200 is stuck on the Initializing step .................................................................................... 9

4.4. The LX200 cannot find home position .......................................................................................... 9

4.5. The LX200’s cords are twisted .................................................................................................... 10

4.6. The program does not launch ..................................................................................................... 11

4.7. The alignment is very far off (more than normal) ...................................................................... 11

4.8. The image shakes excessively ..................................................................................................... 11

5. Maintenance ....................................................................................................................................... 11

5.1. Accessing the Dome .................................................................................................................... 11

5.2. Cleaning the Quartz Mirrors ....................................................................................................... 12

5.3. Reattaching a broken photogate ................................................................................................ 12

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1. Heliostat Operators Manual Introduction This document steps a user through the proper methods to use, maintain, and troubleshoot the

Heliostat installed into the Embry-Riddle College of Arts and Sciences (COAS) classroom #501. This

device and it operating software are capable of tracking the Sun or the Moon and projecting a high

resolution image into the classroom below. The resulting image is approximately 24” in diameter and is

intended to be used as a visual aid for studying the sun or the moon.

2. Hardware Overview The Heliostat system consists of several components that will be referred to frequently throughout this

document. There are two mirrors in the system, a primary mirror which is mounted to a robotic

telescope mount, and a secondary mirror that is fixed in space. The robotic telescope mount is called the

Meade LX200 Classic and will simply be referred to as the LX200. The LX200 is an older device which

does not have GPS or home finding capabilities, however this device has been modified so that it can

find a home position via a microcontroller and photo gates which will be mentioned later. Other major

components include a telescope with a 72” objective lens, an eyepiece, the Heliostat’s protective dome,

and a control station computer in the COAS 501 classroom. These components are shown in the

following diagrams.

Figure 1: Schematic of Heliostat System with light rays passing through system. Note: Heliostat Dome NOT shown

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Figure 2: Schematic of Heliostat in its protective dome housing

3. Standard Operating Procedure The standard method of operating the Heliostat is shown in the following procedure.

3.1. Accessing the classroom COAS 501 The COAS 501 classroom is located on the 5th floor of the College of Arts and Sciences. During the

school semester this classroom is often filled with students and ongoing classes. It is not

recommended to operate the Heliostat at this time since the Heliostat may be distracting to

students. During all other hours the classroom can be accessed via a faculty member of the Physical

Sciences Department or by arranging an appointment with Campus Safety by calling 386-226-6480.

3.2. Turn on the Control Computer Inside the classroom on the left side of the back wall (located next to the control room) there is a

computer sitting on the counter. This computer is the control computer for the Heliostat and this

device and its monitor should be turned on. Booting this computer may take several minutes.

3.3. Check to make sure power is connected to the power box Next to the computer there should be a grey colored electrical box with black switches. This is a

power control box which sends power to various devices in the Heliostat System. There should be a

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three prong power extension cable connecting power from the wall to the power inlet on this box.

All switches should be powered off at this time.

Figure 3: Heliostat power control box

3.4. Click icon to run the Heliostat Once the computer has finished its startup procedure, click the icon on the desktop to

run the Heliostat.

3.5. Choose an object to track After several seconds, the user interface for

the Heliostat should launch. On the right

side, all real time information is shown to

the user, including webcams, a live radar,

and temperature readings of equipment in

various locations. There are also buttons for

controlling the dome which will become

available to the user at a later stage in the

process. On the left side of the screen the

user can choose to track the Sun or the

Moon. The user should choose the Sun if it

is daytime, and choose the moon if it is

night time and the moon is visible in the

sky. This is easy to verify by briefly stepping Figure 4: Start Screen - Select and object to track

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outside onto the 5th floor veranda and

looking up in the sky.

3.6. Check local weather conditions After selecting an object, an enhanced

radar map with weather conditions will be

displayed. If the weather is deemed

acceptable by the user, then click next to

continue the process. NOTE: The heliostat

should not be operated in inclement

weather. Running the system in inclement

weather will likely cause severe and

permanent damage to the electronics and

optics in the dome.

3.7. User Authentication A dialog box will appear requesting the user

to enter a password to continue. The

password is: ERAUPhysics

Figure 5: Check local weather

Figure 6: User Authentication

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3.8. Power on “Smart Devices” At this time, the user must turn on the

LX200 and the Microcontroller from the

grey power box mentioned in Section 3.3.

These switches are labeled appropriately on

the power box. Once the devices are

powered on and communicating, a green

checkmark will appear. When a green

checkmark appears by both devices, click

next to continue.

3.9. Power on Auxiliary Devices Now it is recommended to turn on the Lens

Cap Remover and the Focus Adjuster.

Turning on the Lens Cap Remover will

remove the protective shutter from above

the objective lens. This can be verified by

watching the webcams and by listening for

a distinct thud when the device is powered

on. Turning on the Focus Adjuster will

enable the user to move the focuser by the

eyepiece to adjust the focus of the image

when the Sun or Moon is being tracked.

During nighttime it may be helpful to also

turn on the light in the dome by switching

on the “LIGHT” on the power box. Click

Next when completed.

3.10. Alignment Procedure At this time the system will take over and

will move the equipment into position. It is

recommended to keep an eye on the

webcams for any weird behavior.

In the event of an emergency, i.e. if at any

time the LX200 begins to act erratically or if

the cords on the LX200 become noticeably

tangled, promptly turn off the LX200 from

the power control box.

Figure 7: Power on Smart Devices

Figure 8: Power on Auxiliary Devices

Figure 9: Alignment Procedure

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3.11. Tracking Procedure The system will begin tracking the sun. If

the dome is not aligned properly the user

can move the dome via buttons in the

bottom right hand corner of the screen.

When the dome is aligned properly, the

LX200 should be visibly illuminated from

outside light.

There is no guarantee that the LX200 will be

exactly aligned to reflect light through the

telescope and into the classroom below. To

properly project an image will require the

user to adjust the alignment via left hand

side of the user interface. The user should

click the up and down adjustment buttons

by the altitude and azimuth to adjust the

position of the reflected sun, so that the

light goes through the telescope objective,

and so that the projected image is centered

below the eyepiece in the classroom below.

When the user is done with the system,

click Stop.

3.12. Shutdown Procedure The system will take control once again and

will move the LX200 to its stowed position

with the primary mirror pointing

downward. The dome will also be closed

automatically. This process takes 1-2

minutes. DO NOT TURN OFF POWER TO

ANY ELECTRONICS YET!

Figure 10: Tracking the Sun

Figure 11: Shutdown procedure

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3.13. Power Off Electronics When instructed, power off all electronics

to the system and click the Close Program

Button

4. Troubleshooting Trouble shooting

4.1. The microcontroller shows a red X This means that the microcontroller is either not turned on or the computer is not able to

communicate with the microcontroller. Check to make sure power is turned on to the

microcontroller. If that does not work, try:

1. Turn off the microcontroller

2. Disconnect the red USB cable from the computer

3. Wait 5 seconds

4. Reconnect the red USB cable to the same port in the computer

5. Turn on the microcontroller

If this does not fix the problem, then the communication port may be blocked by another program

or by another instance of the Heliostat program. To fix that try:

1. Turn off the microcontroller

2. Close the Heliostat Program

3. Logout of Windows

4. Re-login to Windows

5. Restart the Heliostat Program

6. Turn on power to the microcontroller

7. Step through the start up procedure in the user interface

This should resolve the microcontroller issue. To farther troubleshoot, try opening TeraTerm,

connecting to COM3, setting the baud rate to 4800, and looking for outputs from the

microcontroller. Data packets should be formatted in this manner:

a11[1/2]11b11[3/4]11c11[5/6]11d11[7/8]11e[integer]f[integer]g[integer]h11[0/9]11i

where [1/2] means either a 1 or a 2 would appear, and [integer] means some number would appear.

Figure 12: Power off all electronics

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Between Characters Reporting Device

a and b Photogate 1 (LX200 Right Ascension)

b and c Photogate 2 (LX200 Right Ascension)

c and d Photogate 3 (LX200 Declination)

d and e Photogate 4 (LX200 Declination)

e and f Thermistor 1

f and g Thermistor 2

G and h Thermistor 3

h and i Photogate 5 (Dome)

4.2. The LX200 shows a red X This means that the LX200 is either not turned on or the computer is not able to communicate with

the LX200. Check to make sure power is turned on to the LX200. NOTE: The LX200 takes about 10

seconds to boot up and the user should wait 10 seconds after turning on power to check for proper

communication.

If that does not work, try:

1. Turn off power to the LX200





6. Turn on power to the LX200


4.3. The LX200 is stuck on the Initializing step This is a sign that the communication port with the LX200 somehow became blocked. Try these

steps to resolve the problem:






6. Turn on power to the LX200


4.4. The LX200 cannot find home position This problem is indicative of the microcontroller not working. If the LX200 is left on its own to spin, it

could twist the cables and cause permanent damage to the system. If this happens,




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5. Open TeraTerm

6. Connect to COM3 and set the baud rate to 4800

7. Verify the output from the microcontroller has the following output format

a11[1/2]11b11[3/4]11c11[5/6]11d11[7/8]11e[integer]f[integer]g[integer]h11[0/9]11i

where [1/2] means either a 1 or a 2 would appear, and [integer] means some number would

appear.

If the output is correct, then

8. Close TeraTerm


10. Turn on power to the LX200 and microcontroller


If the output is not correct, then

1. Try replacing the USB communication chip

2. Try replacing the microcontroller

3. Try replacing the photogates attached to the LX200 inside the dome

4.5. The LX200’s cords are twisted In the event that the LX200 was shutdown improperly (i.e. the power was cycled when the LX200

was pointing at the Sun) then the cords could become twisted when the next user starts up the

system. Twisting the cords can cause permanent damage to the system!

If the user noticed that the LX200 is in abnormal state when the program is started, action can be

taken to untwist the cables before activating the Heliostat. If the cords are twisted:





5. Restart the Heliostat program to view the webcams, but DO NOT click to track an object

6. Open TeraTerm and organize the windows so both the webcams and TeraTerm can be seen

on the screen

7. Connect to COM5 (Serial to USB Converter)

8. In the command prompt in TeraTerm type the following command. NOTE: all commands are

case-sensitve

9. Type: :Me#

10. The LX200 will begin to turn to untwist the cords

11. When the LX200 is untwisted either

a. Type: :Qe#

b. OR turn off the LX200, wait 3 seconds, then turn it back on

12. Close TeraTerm

13. Continue with using the Heliostat User Interface

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4.6. The program does not launch This is a sign that one or more files are missing from the software package. It is recommended to re-

download the files for the Heliostat. On a computer connected to the ERAU network backup files

can be accessed from the following directory:

S:\COURSES\DesignLab\Heliostat 2014-2015\Backup Files

Transferring the folders in this directory to the host computer and running the file mainGUI.py

through the executable file Python-Portable.exe should run the program.

4.7. The alignment is very far off (more than normal) The program in its current state does not compensate automatically for daylight savings time

changes. To fix this, one value needs to be changed in the runLX200.py file. The line containing:

self.lx200.write(':SG+04.0#') #Set the number of hours added to local time to yield UTC

should be changed to either +04.0 hours or +05.0 hours depending on time of year.

4.8. The image shakes excessively It has been documented that the image from the Heliostat shakes from vibrations in the COAS

building. IT is recommended to operate the Heliostat with all guests in COAS 501 standing still. Also

operating the system when many people are moving throughout the building (as during passing

periods) is not recommended. It is also not recommended to run the system in excessive winds.

4.9. Webcams don’t work Webcams may become non-functional when other programs (or other instances of the Heliostat

Program) are using a webcam. Try:





If this does not work, try downloading and reinstalling the drivers for the webcams. The driver can

be found by googling: Logitech C310 webcam driver.

If this still does not fix the problem, one or more of the webcams may be permanently damaged and

may need to be replaced. Replacement webcams should operate on USB 2.0.

5. Maintenance

5.1. Accessing the Dome Accessing the dome will require the involvement of Campus Safety by calling 386-226-6480. The

dome is accessed by climbing up the ladder at the top of the central COAS stairwell. The hatch at the

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top of the ladder uses the “MRM” key and is where campus safety is needed to get onto the roof.

Once on the roof climb down a short ladder to reach the Heliostat. The heliostat can be opened via

the remote control (acquired through Damon Burke) or by opening the dome from the control

computer in 501. Using a small step ladder, climb into the dome. DO NOT touch the high voltage

rails on the inside edge in the dome painted orange. Once inside the dome, power to the dome can

be turned off to prevent electrocution. Then the equipment can be serviced.

Before leaving the dome, be sure to turn the power back on and take extreme caution to exit the

dome without touching the high voltage orange rails on the inside edge of the dome.

5.2. Cleaning the Quartz Mirrors It is not recommended to clean any optics in this system. If, however this is deemed necessary—in

an extreme case—the mirrors can be removed then rinsed with distilled water. First remove the

primary mirror by unlocking the LX200 and pointing it upward. Unscrew the four hex head bolts, and

lift the mirror and its housing out of the LX200’s forks. Removing the secondary mirror will require

two people. Similarly unscrew the four bolts on the secondary mirror with a flat head screwdriver

and remove the housing from its mounting crossbar.

The mirrors can be removed from their housing by unscrewing the socket head cap screws that hold

on the retention ring. Flip the mirror and housing over onto a clean, dry cloth, remove the centering

socket head nylon cap screws, and lift the housing off of the mirror. Carefully rinse the mirrors with

distilled water and DO NOT touch the surface of the mirror with your hand or any solid object.

When clean, the mirrors can be re-installed to their housings, and then re-attached to the LX200 and

to the secondary mirror mount.

5.3. Reattaching a broken photogate If a photogate breaks for any reason, the photogate will need to be removed and replaced. This job

can be done from inside the dome and will require a pencil, epoxy, tape, soldering equipment, wire

strippers, and a hobby knife. The photogates are Ormon Electronics EE-SX91 P-Type sensors. Once

new sensors have been acquired, the sensors can be replaced. Using a hobby knife, break away the

epoxy holding the sensor to the LX200, and mark the position that the sensor was in with a pencil.

Cut off all of the wires from the sensor to the cable harnesses that run down into COAS 501. Then

solder on the wires of the new sensor to the cable harnesses, and attach the new sensor to the

LX200 with epoxy and tape to hold it in place. The sensors should be replaced in the exact same

position that the previous sensors were in previously, as depicted in the pictures below.

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Figure 13: Pictures of photogates attached to the LX200

heliostat operators manual

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