diff --git a/assignments/DirectedStudy/Tobias/Scenes/BoxPositionInterpolator.x3d b/assignments/DirectedStudy/Tobias/Scenes/BoxPositionInterpolator.x3d
index 82e9be349291bcec01a7ff00c0c0cfc5d50af988..b07d52662a731bbdb0b9dcf3723eb86a0281a983 100644
--- a/assignments/DirectedStudy/Tobias/Scenes/BoxPositionInterpolator.x3d
+++ b/assignments/DirectedStudy/Tobias/Scenes/BoxPositionInterpolator.x3d
@@ -39,6 +39,22 @@
   </Shape>-->
 
 
+<!-- Authoring hint: these axes are aligned within local coordinate system -->
+    <Transform DEF='CoordinateAxesAdjustedScale' scale='4 4 4'>
+      <Inline DEF='CoordinateAxes' url='"../../X3dForWebAuthors/Chapter03Grouping/CoordinateAxes.x3d" "../../../Savage/Tools/Authoring/CoordinateAxes.x3d" "http://X3dGraphics.com/examples/X3dForWebAuthors/Chapter03Grouping/CoordinateAxes.x3d" "https://savage.nps.edu/Savage/Tools/Authoring/CoordinateAxes.x3d" "../../X3dForWebAuthors/Chapter03Grouping/CoordinateAxes.wrl" "../../../Savage/Tools/Authoring/CoordinateAxes.wrl" "http://X3dGraphics.com/examples/X3dForWebAuthors/Chapter03Grouping/CoordinateAxes.wrl" "https://savage.nps.edu/Savage/Tools/Authoring/CoordinateAxes.wrl"'/>
+    </Transform>
+
+
+    <!-- Grid overlay authoring hint:  first adjust grid scale to convenient large size, then adjust overall scale for your scene model. Default block size 1m t 1m. -->
+    <Transform DEF='GridYZ_20x20Fixed_AdjustScale' scale='1 20 20'>
+       <Inline DEF='GridYZ_20x20Fixed' url='"GridYZ_20x20Fixed.x3d"
+          "../../../Savage/Tools/Authoring/GridYZ_20x20Fixed.x3d"
+          "https://savage.nps.edu/Savage/Tools/Authoring/GridYZ_20x20Fixed.x3d"
+          "GridYZ_20x20Fixed.wrl"
+          "../../../Savage/Tools/Authoring/GridYZ_20x20Fixed.wrl"
+          "https://savage.nps.edu/Savage/Tools/Authoring/GridYZ_20x20Fixed.wrl"'/>
+    </Transform>
+
 
 <TimeSensor DEF='BoxTimeInterval' cycleInterval='60' loop = 'true'/>
 <PositionInterpolator DEF='Entity' key = '0.0 0.006547418950783975 0.008185345084165307 0.010156249201367895 0.01179876759221886 0.013433768520499673 0.015071065577515301 0.016712947028545994 0.01867372301626076 0.020305924554714194 0.02161361704991965 0.023480361847870935 0.024886685653764076 0.026615269554897805 0.028254037077918265 0.03422338989280303 0.03919198443476348 0.04353634649903669 0.04358343286500957 0.06336436960218075 0.06561250767374874 0.08283609171524511 0.08850522569805262 0.09318260506341994 0.0933699282782172 0.1024758401255888 0.10322680003714696 0.10902212673891452 0.12641120504531828 0.13870689578571518 0.14436074321283612 0.16173386656991473 0.17900548845538714 0.1921524138800353 0.19219877680818762 0.19467783308669606 0.19612806642291533 0.19925754834628798 0.20519606069234414 0.205383942212416 0.21220850075611047 0.21875580961853044 0.21922416483625104 0.23631116067184413 0.23635910415436528 0.23883410289031495 0.24586215191140529 0.2459089316026499 0.25291199056511265 0.25914799312450987 0.27659097541199984 0.2791613578518992 0.29332480777588715 0.30424943444068864 0.31624233499936344 0.3181331105144846 0.3197952875417638 0.3211294326981471 0.32280194230473297 0.3241305830429163 0.32582437115757207 0.33758322385438705 0.3376299642283588 0.34422384046875 0.34470697898106456 0.3461828471791862 0.3614176456077849 0.3788458917814082 0.39621750535520917 0.41179036155928217 0.4313845727042035 0.4484559595824726 0.45065471515933286 0.45556486850691946 0.475159205467114 0.4925653946506649 0.5054232044410905 0.5076212758974029 0.514261617290856 0.5178716113327164 0.518666803176238 0.5281590701370609 0.5336333870328646 0.5510284022474697 0.5558065989638955 0.5573098083935615 0.5589454462616626 0.5612349696946393 0.5628720544383814 0.5648375249084753 0.5664804128816912 0.568070474167097 0.5719632773526139 0.5726695885691163 0.5739379087472832 0.5753039087581349 0.579845651395602 0.5857971148513371 0.5869228155539445 0.5999469374085529 0.6032677529085543 0.6107684270031973 0.6108618920242317 0.6283438691829406 0.6284358244206973 0.642827125804343 0.6435744763902529 0.6528501130410912 0.6599229680263288 0.6599700622557562 0.6740258300328449 0.6740732781177281 0.7025331647094135 0.7060441421313124 0.7234440720050244 0.7247538325887821 0.727941307489618 0.7366026825231655 0.7374040235881619 0.7389464873830478 0.7413368124401738 0.7436311954880757 0.7501289331328781 0.7526981124642281 0.7701041758325059 0.7781951594618157 0.7782887896153962 0.780489385240626 0.783198699195891 0.790583929913973 0.7952650051029888 0.8072914747492286 0.8078982739481312 0.8192247467318894 0.8235294298043958 0.8320889966916089 0.8355500569038891 0.8382141009511871 0.8487299537935545 0.85807800499754 0.8629973743138841 0.8857193216952634 0.8877313123626009 0.8893695844879833 0.8910047662757193 0.8926442886903786 0.8939558500052331 0.8955919989978813 0.8972276604563462 0.8985827853095256 0.9032123784614632 0.9060326143069108 0.9085595826141222 0.9144628666836989 0.9160571820980279 0.926212621363575 0.9355779092599805 0.9491337343223357 0.9631450421272784 0.9652143495149861 0.982623031413636 1.0 ' keyValue = ' 0 0 0