From a6e14085046c7cf24f8ed27673a9c365d1565bf1 Mon Sep 17 00:00:00 2001 From: jaseg Date: Tue, 13 Jul 2021 15:58:30 +0200 Subject: Give source on motor power estimate compare to large sunon fan --- paper/Makefile | 12 +++++++----- paper/ihsm_paper.tex | 10 +++++++--- 2 files changed, 14 insertions(+), 8 deletions(-) (limited to 'paper') diff --git a/paper/Makefile b/paper/Makefile index 051e628..e230536 100644 --- a/paper/Makefile +++ b/paper/Makefile @@ -15,16 +15,18 @@ brief_tex ?= ihsm_tech_report sub_stem ?= cant-touch-this-ihsm-paper VERSION_STRING := $(shell git describe --tags --long --dirty) +SHORT_VERSION_STRING := $(shell git describe --tags) all: ${main_tex}.pdf ${brief_tex}.pdf .PHONY: submission-outputs submission: diff cover-letter ${main_tex}.pdf - cp ${main_tex}.pdf ${sub_stem}-${VERSION_STRING}.pdf - cp ${main_tex}_diff.pdf ${sub_stem}-${VERSION_STRING}-diff.pdf - cp tches-22-01-changes.pdf ${sub_stem}-${VERSION_STRING}-cover-letter.pdf - rm -f ${sub_stem}-${VERSION_STRING}-supplementary.zip - zip -r ${sub_stem}-${VERSION_STRING}-supplementary.zip ${sub_stem}-${VERSION_STRING}-diff.pdf ${sub_stem}-${VERSION_STRING}-cover-letter.pdf + cp ${main_tex}.pdf ${sub_stem}-${SHORT_VERSION_STRING}-revised.pdf + cp ${main_tex}_diff.pdf ${sub_stem}-${SHORT_VERSION_STRING}-diff.pdf + cp cant-touch-this-ihsm-paper-v2.0.pdf cant-touch-this-ihsm-paper-v2.0-original.pdf + cp tches-22-01-changes.pdf ${sub_stem}-${SHORT_VERSION_STRING}-cover-letter.pdf + rm -f ${sub_stem}-${SHORT_VERSION_STRING}-supplementary.zip + zip -r ${sub_stem}-${SHORT_VERSION_STRING}-supplementary.zip ${sub_stem}-${SHORT_VERSION_STRING}-diff.pdf ${sub_stem}-${SHORT_VERSION_STRING}-cover-letter.pdf ${sub_stem}-${SHORT_VERSION_STRING}-revised.pdf cant-touch-this-ihsm-paper-v2.0-original.pdf .PHONY: cover-letter cover-letter: tches-22-01-changes.pdf diff --git a/paper/ihsm_paper.tex b/paper/ihsm_paper.tex index 851da46..f4cea28 100644 --- a/paper/ihsm_paper.tex +++ b/paper/ihsm_paper.tex @@ -420,9 +420,13 @@ motor requires more power than the mesh monitoring circuit of a traditional HSM. Uninterruptible Power Supply (UPS) can be used, but in practice a productized IHSM might have a smaller backup battery integrated into its case. Conservatively assuming an average operating power consumption of $\SI{10}{\watt}$ for an IHSM's motor, a single large laptop battery with a capacity of $\SI{100}{\watt\hour}$~\cite{faa2018} could already power -an IHSM for 10 hours continuously. If a built-in battery is undesirable, or if power outages of more than a few seconds -at a time are unlikely (e.g.\ because the IHSM is connected to an external UPS or generator), the IHSM's rotor itself -can be used as a flywheel for energy storage. +an IHSM for 10 hours continuously. $\SI{10}{\watt}$ is a reasonable high estimate given that there are large industrial +fans rated at lower wattages. For example, \texttt{CF2207LBL-000U-HB9}, a $\SI{250}{\milli\meter}$ diameter +$\SI{7.8}{\meter^3\per\minute}$ industrial axial fan made by Sunon is rated at only +$\SI{6.6}{\watt}$\footnote{\url{https://www.digikey.com/en/products/detail/sunon-fans/CF2207LBL-000U-HB9/9083282}}. If +a built-in battery is undesirable, or if power outages of more than a few seconds at a time are unlikely (e.g.\ because +the IHSM is connected to an external UPS or generator), the IHSM's rotor itself can be used as a flywheel for energy +storage. \paragraph{Spurious alarms.} Even with all components working to their specification, an IHSM could still catastrophically fail if for some reason -- cgit