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Topic: Heliostat


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In the News (Thu 18 Apr 19)

  
  Heliostat
This was to hold the Heliostat that directed the sun's rays to the Gaertner wavelength spectrometer.
The heliostat at the left is by the Societe Genovoise, and is in the collection of the United States Military Academy at West Point.
This large heliostat, made by the firm of E.S. Ritchie and Sons of Boston, stands about 65 cm high, and is remarkably heavy, probably due to the massive driving spring.
physics.kenyon.edu /EarlyApparatus/Optics/Heliostat/Heliostat.html   (500 words)

  
  Heliostat - LoveToKnow 1911
One of the simplest consists of a plane mirror rigidly connected with a revolving axis so that the angle be tween the normal to the mirror and the axis of the instrument equals half the sun's polar distance, the mirror being adjusted so that the normal has the same right ascension as the sun.
Many other forms of heliostats have been designed, the chief difference consisting in the mechanical devices for maintaining the constant direction of the reflecting ray.
One of the most important applications of the heliostat is as an adjunct to the newer forms of ' horizontal telescopes (q.v.) and in conjunction with spectroscopic telescopes in observations of eclipses.
www.1911encyclopedia.org /Heliostat   (686 words)

  
 Modular natural lighting system - Patent 4349245
In the illustrated embodiment, heliostat 20 is a two-axis heliostat, having a longitudinal axis 18 (the polar axis) and a transverse axis 19 (the declination axis).
Heliostat 20 is driven by a motor 14 in the longitudinal axis 18 and by an induction motor 14a in the transverse axis 19, the motors 14 and 14a being under the control of the silicon controlled rectifier 15.
Heliostat 20 is provided with a suitable weatherproof housing 22 and a light weight mirror 26 protected by an entrance window 24 made of a suitable plastic, such as methyl methacrylate.
www.freepatentsonline.com /4349245.html   (3581 words)

  
 APP - Current Research > Solar thermal energy > Multi tower solar array (MTSA) technology
The heliostat field is a special kind of Fresnel reflector which has performance limitations due to mutual blocking and shading of the heliostats.
In regions further away from the towers, the heliostats are alternately directed to two, three, or four aiming points on different towers.The MTSA approach reduces the losses occurred by mutual blocking of the heliostats more distant from the towers.
The overlapping heliostat fields of a Multi Tower Solar Array increase the Annual Ground Area Efficiency and the Annual Reflector Area Efficiency substantially in contrast to conventional solar tower systems with a single central receiver, which means a more efficient usage of the solar radiation falling on a given ground area.
www.physics.usyd.edu.au /app/research/solar/mtsa.html   (1194 words)

  
 Chapter 10
Another heliostat design concept, not so widely developed, uses a thin reflective plastic membrane stretched over a hoop.  This design must be protected from the weather but requires considerable less expenditure in supports and the mechanical drive mechanism because of its light weight.  Membrane renewal and cleaning appear to be important considerations with this design.
Heliostat packing density is the ratio of mirror area to field area.  The average heliostat packing density from optimized ray trace analyses of shadowing and blocking is typically in the range of 0.2 to 0.25 (Battleson, 1981).
The process of laying out a heliostat field consists of segmenting the land area around the tower into a number of concentric zones.  Equations (10.2) and (10.3) are used to determine the average or central radial stagger pattern within these zones, and Equation (10.5) is used to calculate the local field density.
www.powerfromthesun.net /Chapter10/Chapter10new.htm   (3171 words)

  
 Solar Tower Array Ray-tracer Manual
Heliostat size is the size array that defines the approximate size of the heliostat.
If the heliostat field is focused towards the source then this variable is used to calculate the vector from the telescope to the source.This value is also used to orient the secondary mirror in the autofocus option.
During the canting calibration the heliostat is positioned so that if treated as a single planar surface it would direct a ray from the source to the target through the center of the heliostat plane (point 0,0,0 in heliostat coordinates).
www.physics.purdue.edu /astro/KASCADE/STARt/startmanual.html   (2845 words)

  
 What are Heliostats?
Simple heliostats use an ordinary clockwork mechanism to follow the sun, while more complex heliostats track the sun directly by sensing its position in the sky or incorporate microprocessing software that compansates for the angle of the sun throughout the solar year.
The word heliostat is a compound of the Greek word for 'sun', helios, and the word for 'still' or 'stationary', stat, and it appears to have been coined in the mid 18th century.
Heliostats are most commonly used to position mirrors and reflect sunlight continuously in a specific direction, although strictly speaking, heliostat refers to the positioning device and not the mirror.
www.wisegeek.com /what-are-heliostats.htm   (439 words)

  
 Spartanburg SC | GoUpstate.com | Spartanburg Herald-Journal
History: The heliostat was originally developed as an instrument for use in surveying, allowing the accurate observation of a known point from a distance.
Heliostats have been used for sunlight-powered interior lighting, solar observatories, and solar power generation.
As the earth turns, a heliostat should move about four times a minute (approx.) A computer is required for heliostats whose primary axis is aimed "the wrong way." No computer is needed if the primary axis aims directly at the target-receiver.
www.goupstate.com /apps/pbcs.dll/section?category=NEWS&template=wiki&text=heliostat   (597 words)

  
 NREL Researchers Test Solar Thermal Technology
The heliostat is a large tracking mirror for use in solar thermal power plants.
The heliostat is a critical component, and a field of heliostats accounts for 50-60 percent of the cost of a power plant.
During the next phase of the project, additional heliostats will be installed at Sandia National Laboratories in Albuquerque, NM for optical testing and at Solar Two, a pilot power tower plant in Daggett, Calif., for extended field tests.
www.nrel.gov /news/press/1997/47helios.html   (517 words)

  
 ObservatoryScope Heliostats
Heliostats and Siderostats for Solar, Planetary and Lunar Observations
Radio interference from the heliostat's operation is almost nonexistent since the heliostat's drive system electronics are contained within the heliostat's fully shielded computer case.
Don't forget that the heliostat's or siderostat's observing station and control room can be located on the ground floor of the building and that the observing station will be conveniently located at desktop height.
www.observatoryscope.com /heliostat/heliostat.html   (738 words)

  
 Mini-Heliostat FAQ
In solar energy applications a heliostat is a mirror that reflects the sun's rays to a fixed target and is adjusted to follow the sun so that the target is always illuminated.
Heliostats are designed to last for 20 years and withstand winds up to 120 km/h.
Both of these guys have built smallish heliostats (mirrors on the order of 2 square metres) for significantly less money than the US spends, but the systems are made of glass and metal and probably will need a lot of start-up money to get out of the "garage-built" stage.
people.linux-gull.ch /rossen/solar/miniheliostatfaq.html   (2865 words)

  
 Definition of Heliostat   (Site not responding. Last check: )
Heliostat -- A mirror that reflects solar rays onto a central receiver.
A heliostat automatically adjusts its position to track daily or seasonal changes in the sun's position.
The arrangement of heliostats around a central receiver is also called a solar collector field.
www.teachmefinance.com /Scientific_Terms/Heliostat.html   (81 words)

  
 A HISTORY OF THE MCMATH-PIERCE SOLAR TELESCOPE
The heliostat is the configuration that was eventually chosen for the solar telescope.
The heliostat diameter for the solar telescope was chosen to be 2-m.
The heliostat fed the solar beam down to a 0.92-m Kanigen-coated aluminum spherical mirror with a 39-m focal length (Pierce 1969) and a 0.92-m aluminum folding flat mirror.
nsokp.nso.edu /mp/cphistory.html   (12957 words)

  
 Newsworthy Articles
The central heliostat has a 60-inch aperture and the East and West auxiliary heliostats carry 36-inch diameter flat mirrors.
The heliostat minus the mirror and its cell were removed from the "Super Carriage" that carries all three heliostats and was trucked to DFM Engineering's facilities in Colorado.
The refurbished heliostat points twice as good as required and the tracking is superb.
www.dfmengineering.com /news_mcmath_pierce.html   (739 words)

  
 Wind resistant two axis tracker for energy or radiation concertrators - Patent 4870949
Conventional heliostats and dishes usually have a single pedestal for support and a separate azimuth and elevation drive system attached to the top of the pedestal and attaching to the center of the back of the reflector module.
For heliostats the wind loading is carried to the foundations through the elevation drive foundation and the tension members or guy wires which anchor it.
Deployment of this heliostat is simplified, since it can be assembled in a protected area and with the reflector rotated be nearly parallel to the elevation drive ring.
www.freepatentsonline.com /4870949.html   (3316 words)

  
 Heliostat | Rob Milne
This heliostat was started in 1991 while I was doing my tool and die apprenticeship and took more than a decade to complete.
The process of teaching myself all the required skills propelled me into mech and embedded sw engineering.
I received funding from the Ontario Arts Council for a project which this piece was one component of.
robmilne.ca /heliostat   (114 words)

  
 Heliostat | A concept in energy production.
new picture 7-13-2007, note the one reflection off the shed all three heliostats are aligned.
Heliostats have been attempted in the past but so far have been proven inefficient not only cost wise but technologically as well.
I'm in the process of creating a unit that is small, affordable, and overall cheap to maintain.
www.heliostat.us   (303 words)

  
 Floppy drive heliostat - Hack a Day
This is an ongoing project to build a heliostat from a floppy drive.
Heliostats are used by solar arrays to track the sun.
I have also been inventing some heliostats that use phototransistors or cds cells to determine the direction of the sun...not unlike the floppyostat.
www.hackaday.com /2005/11/29/floppy-drive-heliostat   (1360 words)

  
 University of Cincinnati News: Weather Tower, Heliostat Aid Teaching
A heliostat is a telescope specially designed to safely observe the sun and will be used in astronomy courses.
According to Margaret Hanson, assistant professor of physics and an astrophysicist who originally conceived of the heliostat project, the sunlight reaches the classroom from the roof through a 40-foot 8-inch diameter tube and three 6-inch mirrors.
The heliostat, which has been funded by a $30,000 Ohio Board of Regents grant, will be housed in a 7-foot-diameter dome that will be placed on the east side of Braunstein's roof.
www.uc.edu /news/tower.htm   (527 words)

  
 NSO/KP: History of the MP Facility
In the final design the heliostat sits atop a massive concrete cylinder 26 feet in diameter with steel reinforced walls which are 4 feet thick.
The heliostat base frame tips the scales at an enormous 27 tons, and had to be manufactured in four parts.
The second fused quartz disk, 63" in diameter, was cast at the General Electric plant and served as the main heliostat mirror until 1966 when it was replaced with a larger 82" diameter quartz mirror.
nsokp.nso.edu /mp/history.html   (1077 words)

  
 EGIS - Heliostat
The term "Heliostat" has its origin in the astronomical science and circumscribes the technique required to track moving stars (especially the sun, Greek: helios) with an astronomical telescope automatically.
The Heliostat in effect consists out of three constructional- und functional groups: The reflector (mirror), the twin-axis-rotor, which holds and moves the mirror, and a computer with an astronomical program.
The advantage of this characteristic is the ability, to hide the Heliostat deep in the background and not to disturb the aesthetic actualities at the location.
www.egis-rotor.de /h_faq_us.html   (1739 words)

  
 Automatic heliostat track alignment method
New coefficients are established for the heliostats' track alignment system to automatically correct for errors in the system, this eliminates the need for resurveying and field work normally associated with aligning heliostats.
A heliostat tract alignment method as recited in claim 1 wherein determining the sunbeam centroid position error generally consists of detecting the sunbeam centroid on the reference target utilizing a digital image radiometer to determine the actual sunbeam centroid position and comparing the actual sunbeam centroid position to the reference position.
A central control means connected to the heliostat control means for automatically selecting a heliostat to be supervised, comparing its track alignment data to the track alignment reference data stored in the memory means, and commanding the heliostat control means to reposition the heliostat to correct for alignment errors.
www.processpatrol.com /chelator_compositions_comprising_oxime_compounds/automatic_heliostat_track_alignment.html   (415 words)

  
 Solar Telescope Design   (Site not responding. Last check: )
It consists of three primary parts, the heliostat, the telescope, and the spectroscope.
The heliostat tracks the sun, or any observable object, and directs the light to the telescope.
The heliostat consists of a two flat mirrors, one 10” and an 8”; one mirror tracks and the other redirects the light into the telescopes 6” f/15 objective lens.
www.bu.edu /astronomy/facilities/solar_telescope/details.html   (411 words)

  
 Tech Undergrads Earn Grant For Solar Collector
A heliostat is a device that uses mirrors to reflect a beam of sunlight in a fixed direction.
Slingsby described the team’s device as “a bunch of mirrors in an array that reflect light to a specific point.” The purpose is to create electric energy by focusing the sunlight on a central receiver where the collected heat is used to power electrical generation equipment.
Among project goals are that the natural energy system be easy to maintain, defined as “all parts can be replaced within one hour”; and, that it be maintenance-efficient (able to operate up to 25 years with minimal maintenance, defined as only replacing a major component every 10 years with regular maintenance and inspection).
www.mymountainmail.com /stories/nmttechundergrads10-19-0620061019.php   (1035 words)

  
 heliostat   (Site not responding. Last check: )
This type of heliostat, along with the secondary directional mirror on the left, was sold by the John A.
The nameplate is lacking on this instrument, and it is not clear if the Brashear Company made this heliostat or was acting as a dealer.
The cover plate of the heliostat with the key used to wind the clock on one of the two shafts used for that purpose.
www.uvm.edu /~dahammon/museum/heliostat.html   (229 words)

  
 Weekly Team Progress Report Blog   (Site not responding. Last check: )
The steel needed to assemble the mirror housing and the base structure of the heliostat will also be evaluated with the FEA results and verified with hand calculations.
Included in the attendees were a number of prominent members of the “heliostat community” as well as a number of other engineers associated with solar energy programs.
Work is ongoing for the control system of the heliostat, but erection of the prototype can begin prior to the control system completion.
infohost.nmt.edu /~helio/progress/progress.htm   (2111 words)

  
 STPNS - Tech Undergrads Earn Grant For Solar Collector, Socorro, New Mexico   (Site not responding. Last check: )
A heliostat is a device that uses mirrors to reflect a beam of sunlight in a fixed direction.
Slingsby described the team’s device as “a bunch of mirrors in an array that reflect light to a specific point.” The purpose is to create electric energy by focusing the sunlight on a central receiver where the collected heat is used to power electrical generation equipment.
Among project goals are that the natural energy system be easy to maintain, defined as “all parts can be replaced within one hour”; and, that it be maintenance-efficient (able to operate up to 25 years with minimal maintenance, defined as only replacing a major component every 10 years with regular maintenance and inspection).
www.stpns.net /view_article.html?articleId=21841079819722099   (1057 words)

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