type

type
reference

Core services

Part of Project Yukart, making an old 2008 Mitsubishi Z27AG a bit smarter with modern technologies.
This file serves as the minimalist portal to other docs

What this repo is about

The acquisition and processing cluster on the Orin, developed and deployed as one unit: recorder, decoder, gnss, imu, orin-status and obd-poller now; can-bridge as it is needed.

Binary	Installed as	Does
recorder	yukart-recorder.service	Raw CAN + GNSS to disk, in sessions, under a storage bound; every yukart/vehicle/* value (decoded and OBD-II) beside them
decoder	yukart-decoder.service	The car's own broadcast frames to named signals (yukart/vehicle/*): every z27ag signal in contracts' signals.json, laid out by its can block. Sent on change (booleans at once, numbers at most every 50 ms); a value that has not changed is re-sent once a second, so svc-gw never marks a steady one stale; reads only
bus-bench	not installed: a test tool	Raw CAN and decoded-signal load over MQTT, measured: loss, latency, broker CPU (report)
obd-poller	yukart-obd-poller.service	OBD-II mode 01 on the K-line through the Bluetooth ELM327 (address in /etc/default/yukart-elm), the single writer to the car; never on CAN. The obd_* signals, calibration references (yukart/vehicle/*): rpm, speed, throttle, load, MAF, timing, O2 every round; temperatures and trims every 5 s. Lets go of the adapter after a minute of ECU silence
gnss	yukart-gnss.service	gpsd's fix as single values on yukart/gnss/*: fix, speed, heading, position, altitude, satellites
imu	yukart-imu.service	The WT61 (plus) on any USB-UART adapter, found by itself (adapter and speed), turned into the car's frame (--forward, --right): roll, pitch, gravity-free longitudinal and lateral g, yaw rate on yukart/imu/*, at most every 40 ms. Never writes to the module
orin-status	yukart-orin-status.service	The Orin's health on the bus, once a second: temperatures, CPU/GPU load, memory, power, fan, WiFi (with SSID)/LTE/tablet links, the CAN interface, the ELM's Bluetooth link, UPS battery (yukart/host/*). Powers the Orin off cleanly when the UPS pack stays below 11.0 V while discharging for 30 s

scripts/deploy-recorder.sh                 # build, glibc check, install on the car Orin
scripts/deploy-native.sh BIN               # build BIN on the development Orin, glibc check, install;
                                           # deploy-{decoder,gnss,obd-poller,orin-status}.sh wrap it.
                                           # Redeploy after any contracts signals.json change
yukart-decoder --list                      # the signals it decodes, and where
zstdcat can-*.log.zst | yukart-decoder --replay   # what it would publish for a recording
scripts/replay-session.sh SESSION_DIR [SKIP_S]   # on the Orin: replay a session's frames through a
                                           # decoder on vcan_replay, live to displays; never recorded
yukart-obd-poller --elm ADDR --once        # on the Orin, service stopped: adapter, protocol,
                                           # supported PIDs and one value each
yukart-gnss --once                         # the next fix as JSON, no broker
yukart-imu --once                          # find the WT61, 3 s of readings as JSON, no broker
yukart-orin-status --once                  # on an Orin: one reading as JSON, no broker
yukart-recorder ctl status                 # on the Orin
yukart-recorder ctl start "cold start"     # manual session, ends only on stop
yukart-recorder ctl mark "indicator left on"
yukart-recorder ctl stop

Recordings live in /var/lib/yukart/recordings/, one directory per session — layout in the initial plan.

• For implementation practice guidelines, refer to the guidelines;
• For implementation plans and history, refer to them;