Value chain · CLM-1407
In plain terms
Most designs turn their solar panels to face the Sun and their antenna to face the Earth, and pass the power across a turning joint between the two. CASSIOPeiA is meant to fix its panels and its antenna together and steer the beam electronically, so it needs no such joint.
The claim as recorded
CASSIOPeiA is designed with no rotating joint between its Sun-facing and Earth-facing parts. SRC-026 sorts solar power satellite concepts by how they overcome "the rotational mismatch between the satellite's Sun-pointing and Earth-pointing sub-systems". The 1979 NASA reference system and CAST's multi-rotary-joint design pass "Electrical power over articulated joint(s)". The Modular Symmetrical Concentrator and SPS-ALPHA pass "Optical power over articulated joint(s)". CASSIOPeiA is placed in "Solid-state other". The patent says "A rotating joint is generally less reliable than a static structure", and that in its power beaming apparatus "The relative orientation of the solar array and the phased antenna array may be fixed, so no moving joints are needed between the solar array and phased antenna array" (also its claim 37).
Evidence behind this: Two sources by the concept's inventor: a T2 journal paper (SRC-026) and a T3 patent (SRC-088); the weaker sets the tier. Both describe the intended design; neither reports a built or flown craft.
Scope and limits
NO JOINT BETWEEN ARRAY AND ANTENNA, NOT NO MOVING PARTS. The patent's array has hinged joints and linkages for folding and unfolding (SRC-088 PDF 21 [9], PDF 30 [18]). It may rotate once a year to follow the Sun (CLM-1174), and CLM-1175 has attitude control by switchable reflectors. The patent's "may be fixed" is a disclosed option; claim 37 is a dependent claim. "Solid-state other" is the paper's category label, not a parts list. The phrase "slip ring" appears in neither source. SRC-026 PDF 3's "eliminated complexity of articulated joints" is said of the Tin Can SPS, not of CASSIOPeiA, and must not be cited for it. This is design intent, not a built or flown result.
What it assumes
That the patent's power beaming apparatus is the SRC-026 design; both are by the same inventor (as CLM-1174 assumes).
Where it comes from
PDF 3 [172], normalised: "a means to overcome the rotational mismatch between the satellite's Sun-pointing and Earth-pointing sub-systems"; raw: "i) Electrical power over articulated joint(s): NASA 1979 Reference System, CAST Multi Rotary Joint (MRJ) [9]", and "iv) Solid-state other:" with "CASSIOPeiA SPS [11]" (two text-layer spans; the Fig. 1 caption "Fig. 1. Nasa 1979 reference system." falls between them, so they are joined on the page render, not in the text layer). SRC-088 PDF 14 [2], raw: "A rotating joint is generally less reliable than a static structure." SRC-088 PDF 23 [11], raw: "The relative orientation of the solar array and the phased antenna array may be fixed, so no moving joints are needed between the solar array and phased antenna array." SRC-088 PDF 40 [28], claim 37, raw: "wherein the relative orientation of the solar array and the phased antenna array is fixed so no moving joints are needed between the solar array and phased antenna array".
Basis: categories of power transfer between a satellite's Sun-pointing and Earth-pointing parts
Cite this
energyaperture.com/c/clm-1407
CLM-1407, Energy Aperture, as of 2019.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-026
- CLM-0004The author of the 2019 CASSIOPeiA paper states the beam's strongest point is about 230 watts per square metre, and says that figure was...CLM-0006None of the five main studies mentions the international radio-frequency exposure limits, or any safety standard, or a restricted area...CLM-0013The paper that modern UK studies rely on for the beam figure calls anything below 1 kilowatt per square metre safe, with 230 watts per...CLM-0336Different design studies over four decades have each simply assumed a different working lifetime for a solar power satellite, from about 15...CLM-0339A 2019 paper said solar power satellites are often assumed to need visits in orbit for repairs and refuelling, but that no system yet...CLM-0441A normal geostationary satellite needs a small, regular fuel-based nudge every year to stay in place. One 2019 design proposes cutting most...CLM-0504None of the main CASSIOPeiA-related documents in the register mentions any named safety or exposure standard, or describes any restricted...CLM-0660The 2019 CASSIOPeiA paper does not discuss electric propulsion for getting the satellite to its orbit. It only prices delivery using...More on the source page.
- Also from SRC-088
- CLM-0896The patent describes measuring the incoming steering signal at scattered sensors, not at every antenna, and working out the values in...CLM-0897The satellite aims its beam by listening for a low-power signal sent up from the receiving station, measuring the shape of that arriving...CLM-0899The patent never says the steering signal is protected in any way. There is a difference between scrambling that signal so nobody can read...CLM-0900The satellite can point its beam far further than there is Earth to point at, so moving power from one receiving station to another is not...CLM-0903The shared clock tells every sensor to take its reading at the same moment. How precise that clock must be depends on how fast the thing...CLM-0905Sharing a clock is not the same as being told what to do. The clock and the carrier tell the antennas nothing about where to send the power...CLM-0913When the satellite corrects its own bending by listening to the ground signal, what is left over is not how far the antennas moved. It is...CLM-0942Three documents held here give three different sizes for the same satellite's transmitting antenna. The patent says 1 to 1.5 km across and...More on the source page.