{"id":485,"date":"2020-02-26T18:25:53","date_gmt":"2020-02-26T23:25:53","guid":{"rendered":"https:\/\/increasec.com\/?p=485"},"modified":"2020-03-02T00:23:20","modified_gmt":"2020-03-02T05:23:20","slug":"vehicle-to-vehicle-communications-v2v","status":"publish","type":"post","link":"https:\/\/increasec.com\/?p=485","title":{"rendered":"Vehicle to Vehicle Communications (V2V)"},"content":{"rendered":"\n

In 2017 the US government requested comments to build a V2V standard see here<\/a> . The benefits being that other vehicles can communicate their state, intentions, observed road conditions, etc BETTER than vehicle resident technologies that rely on line-of-sight. Their recommendation was to use the 6Mhz frequency which would require special radios, and have VERY limited data bandwidth. And be susceptible to HALL effect.<\/p>\n\n\n\n

My recommendations and some description why:<\/p>\n\n\n\n

Use LoRa 1km\/50Kbps And\/OR Bluetooth 4+ class 2 ~10m\/3Mbps or class 1.5 ~20m Uses currently developed technology. Will require antenna to increase range. Allows rapid prototyping on Raspberry Pi 0w. No custom hardware.<\/p>\n\n\n\n

Allows integration and expandibility; + camera = dashcam, possibly lane departure alerting, bad driver reporting, find stolen vehicles by plate#. +Carbon Monoxide detector +OBD2 integration = self diagnostic, good driver reporting +wifi=auto update, data upload. Multiple cameras\/mirrors = blind spot detection.<\/p>\n\n\n\n

Low cost of entry; Manufacturers can wire USB power near rear view mirror and leave rest to customer. RasPi0w $10 + Camera $10 + ODBC module $15 + LoRa hat $25<\/p>\n\n\n\n

Government writeup recommended 2 algorithms to start with; Intersection Movement Assist (IMA) and Left Turn Assist (LTA)<\/p>\n\n\n\n

IMA; possible algorithm; <\/p>\n\n\n\n

V2V vehicles beacon their plate # to determine who is present. Signals to non-V2V vehicles; Switch between running lights and low beam (OR 4way flashers? Red\/Y\/Green leds behind RV mirror=easiest to implement) V2V vehicles compare 1st to 0kph. tie=play Rock\/Paper\/Scissors. Winning vehicle changes to low beam lights and proceeds. <\/p>\n\n\n\n

LTA; possible algorithm; <\/p>\n\n\n\n

Listen for speed of oncoming V2V vehicles. Refer to history if you have enough time to proceed given safety margin of ? 2 vehicle lengths? 10%? Is temperature below 1degC? +10%sm, have you or other V2V vehicles reported traction control past 1hr? +10%sm<\/p>\n\n\n\n

What to beacon? plate#\/VIN# = unique ID last 7 digits=49bits. speed 5kph increments 0-150kph 32options=5bits, Acceleration +3 hard accel to -3 hard brake -4=wheels locked still moving 4bits, turn signal status 0=off 1=left 2=right 3=4way 2bits, traction control engaged\/road debris last hour #times 2bits , direction N\/S\/E\/W 2bits, Transmission 0=park 1=reverse 2=fwd 3=cruise control engaged 2bits , (66bits total) GPS is typically 24bits but this can be reduced seeing as it is physically impossible to communicate with a vehicle in a different hemisphere (most of the time) LoRa has a max packet size of 255bytes(2040bits)\/ sf12 max is 51bytes(408bits) , header=13bytes(104bits) =104+90<\/p>\n\n\n\n

City\/County police provide a list of no more than 100? of each item to find; Licence plate #’s, Wireless MAC addresses, Bluetooth MAC addresses, QR codes. Why? a find list allows versitility to emergeny services without privacy concerns of broadcasting every plate#.<\/p>\n\n\n\n

OBD2 relevent info:<\/p>\n\n\n\n

Service 1 <\/p>\n\n\n\n

0D 13 1 Vehicle speed 0-255km\/h<\/p>\n\n\n\n

0F 15 1 Intake air temperature -40 215 \u00b0C<\/p>\n\n\n\n

11 17 1 Throttle position 0-100%<\/p>\n\n\n\n

2F471Fuel Tank Level Input0100%<\/p>\n\n\n\n

33511Absolute Barometric Pressure0255kPa<\/p>\n\n\n\n

A41644Transmission Actual Gear<\/p>\n\n\n\n

A61664Odometer<\/a>hm<\/a><\/p>\n\n\n\n

Service 09<\/p>\n\n\n\n

0217Vehicle Identification Number<\/a>\u00a0(VIN)17-char VIN, ASCII-encoded and left-padded with null chars (0x00) if needed. ea ASCII char=7bits x17=119bits<\/p>\n\n\n\n

Additional sensors required:<\/p>\n\n\n\n

Accelerometer; to determine braking level<\/p>\n\n\n\n

Compass<\/p>\n\n\n\n

Microphone? turn signal status, horn<\/p>\n\n\n\n

? Antilock & traction control status<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

In 2017 the US government requested comments to build a V2V standard see here . The benefits being that other vehicles can communicate their state, intentions, observed road conditions, etc…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-485","post","type-post","status-publish","format-standard","hentry","category-uncategorised"],"_links":{"self":[{"href":"https:\/\/increasec.com\/index.php?rest_route=\/wp\/v2\/posts\/485","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/increasec.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/increasec.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/increasec.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/increasec.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=485"}],"version-history":[{"count":13,"href":"https:\/\/increasec.com\/index.php?rest_route=\/wp\/v2\/posts\/485\/revisions"}],"predecessor-version":[{"id":657,"href":"https:\/\/increasec.com\/index.php?rest_route=\/wp\/v2\/posts\/485\/revisions\/657"}],"wp:attachment":[{"href":"https:\/\/increasec.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=485"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/increasec.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=485"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/increasec.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=485"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}