Robot Mower Communications Standard

Describes message format used to externally control a robot mower (e.g. Ardumower-based).

Requirements

• Serial interface (or serial USB)
• ...

Message format

NMEA 0183 compatible format (ASCII encoded)

message structure: $IDMSG,data,<cr><lf>

message components:

• $: start of message symbol
• ID: RM (robot mower), DW (DW1000 beacons), ...
• data: message data (see below)
• <cr><lf>: end of message symbol

example: $RMSEN,1,1,0,0,0,0,1,0,0,179,0,0,0,0<cr><lf>

Messages

• $RMMOW: Set mowing state (start mowing, stop mowing, go to docking station)
• $RMSTA: Robot state event (robot state, errors, battery, charger)
• $RMSEN: Robot sensor data event (sensor values)
• $RMTRG: Robot sensor trigger event (sensor trigger counters)
• $RMCFG: Robot mower configuration (available sensors)
• $RMMOV: Move robot until sensor trigger
• $RMKOA: Keep ongoing action (mower communications saftety)
• $DWDAT: DW1000 beacons ranging

Set mowing state (start,stop,dock)

$RMMOW,s<cr><lf>

• s: stop mowing (0), start mowing (1), go to docking station (2)

Robot state event (robot state, errors, battery, charger)

$RMSTA,s,e,b,c,h,d<cr><lf>

• s: robot state: stopped (0), mowing (1), busy (2)
• o: docking state: not docked (0), docked (1)
• e: error
• b: battery percent
• c: charging percent
• h: absolute compass heading in degree
• l: left odometry counter
• r: right odometry counter

Robot sensor data event (sensor values)

$RMSEN,bl,br,bc,pfl,pfr,pfc,prl,prr,prc,ih,ip,ir,ga,go<cr><lf>

• bl: bumperLeft
• br: bumperRight
• bc: bumperCenter
• pfl: perimeterFrontLeft
• pfr: perimeterFrontRight
• pfc: perimeterFrontCenter
• prl: perimeterRearLeft
• prr: perimeterRearRight
• prc: perimeterRearCenter
• ih: IMUcompassHeading
• ip: IMUpitch
• pr: IMUroll
• ga: GPSlatitude
• go: GPSlongitude

Robot sensor trigger event (sensor trigger counters)

$RMTRG,bl,br,bc,pfl,pfr,pfc,prl,prr,prc,ip,ir<cr><lf>

• bl: bumperLeft
• br: bumperRight
• bc: bumperCenter
• pfl: perimeterFrontLeft
• pfr: perimeterFrontRight
• pfc: perimeterFrontCenter
• prl: perimeterRearLeft
• prr: perimeterRearRight
• prc: perimeterRearCenter
• ip: IMUpitch
• pr: IMUroll

Robot mower configuration (type of sensors)

$RMCFG,d,pfl,pfr,pfc,prl,prr,prc,ih,ip,o,g

• d: Docking station available (1/0)
• pfl: perimeterFrontLeft available (1/0)
• pfr: perimeterFrontRight available (1/0)
• pfc: perimeterFrontCenter available (1/0)
• prl: perimeterRearLeft available (1/0)
• prr: perimeterRearRight available (1/0)
• prc: perimeterRearCenter available (1/0)
• ih: IMU compass available (1/0)
• ip: IMU pitch/roll available (1/0)
• o: Odometry available (1/0)
• g: GPS available (1/0)

Move robot until sensor trigger

$RMMOV,l,r,p,i,d,o<cr><lf>

• l: left motor target ticks per frame
• r: right motor target ticks per frame
• p: PID_Kp
• i: PID_Ki
• d: PID_Kd
• o: PID_Ko

Keep ongoing action (mower communications saftety)

$RMKOA<cr><lf>

DW1000 beacons ranging

$DWDAT,t,b1,b2,b3,b4,...<cr><lf>

• t: timestamp
• b1,b2,b3,b4,...: beacon ranging in meter

Proprietary

• Any proprietary messages not defined by this protocol