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Skild Robotics Operations

Battery and charging

Scope

Battery handling, swap procedure, charging hygiene, and thermal-management thresholds for the GO2W.

Purpose

Battery and temperature are two of the three monitor-continuously variables (the third is localization). Inattention to any one leads directly to robot failure, hazardous conditions, or loss of mapping progress. [SOURCE: SOP V3 §III Rule 2]

Required inputs / tools

  • Hardware: primary battery (in robot), spare battery, charging brick, robot top shell (must be re-attached after battery operations).
  • Software: Skild tablet/browser metrics view.

Battery — basics

ActionHow
Power onDouble-click the round button on top of the battery pack [SOURCE: SOP V3 §V "Battery Location and Insertion"]
Check charge without powering onSingle-tap the same button
Power downHold the battery power button [SOURCE: SOP V3 §XVIII]
Insert batteryRemove top shell → seat battery on top of torso (connector down) → press firmly → replace shell

Battery — always keep a spare charging

Whenever the robot is operating, a second battery should be on the charger. Battery swaps are the fastest way back into the field — but only if the spare is ready. Treat the charger as part of the active deployment setup, not an afterthought. [SOURCE: SOP V3 §V "Always Keep a Spare Battery Charging"]

Before swapping: confirm the spare is fully charged. Single-tap the spare’s power button to verify. A half-charged swap defeats the purpose. [SOURCE: SOP V3 §V "Check Before You Swap"]

Top shell re-assembly (after battery access)

  1. Orient the shell so the LiDAR arrow faces backward (toward the rear of the robot).
  2. Align over the four screw holes.
  3. Secure with all four screws.

Do not over-tighten. Screw holes are 3D-printed. Excessive torque strips the threads or cracks the casing. Tighten until snug — no further. [SOURCE: SOP V3 §V "Top Case (Shell) Reassembly"]

Thermal & battery thresholds

Automatic (autonomous mode only)

MetricThresholdSystem response
Battery20%Automatic sit / return-to-base [SOURCE: SOP V3 §XVI]
Motor temperature75°CAutomatic sit [SOURCE: SOP V3 §XVI; April 2026 ABM SOP §XVI]

Automatic thresholds apply only in autonomous mode. In teleoperation, there is no automatic intervention. The operator is the sole safety mechanism — check the metrics screen at regular intervals. [SOURCE: SOP V3 §XV "No Automatic Safety Cutoff in Teleop"]

Operator-initiated (both modes)

MetricThresholdOperator action
Battery25%On-site operator notifies remote operator and prepares for battery swap. Proceed only after remote operator acknowledgement. [SOURCE: SOP V3 §XVI]
Motor temperature> 75°C (in teleop)Sit the robot and let it cool. Use the cooldown window to check whether it is a convenient time to swap the battery. [SOURCE: SOP V3 §XV + §XVI; April 2026 ABM SOP lines 552, 598]

The 25% rule — plan ahead

Do not wait for the 20% auto-return to trigger. At 25%, ship a heads-up to the remote operator on Slack and stage a spare battery. The swap happens only after explicit remote acknowledgement so a run is not interrupted mid-critical-goal. A half-prepared swap is worse than running the battery down to auto-return. [SOURCE: SOP V3 §XVI "The 25% Rule"]

Other operating guidance

  • Maintain battery above 25% as best practice. [SOURCE: SOP V3 §XVI "Operator Monitoring Responsibilities"]
  • Operate well below 75°C whenever possible. [SOURCE: SOP V3 §XVI; April 2026 ABM SOP line 604]
  • Mapping must begin at 100% battery — if the robot dies mid-map, all progress including glass marking is lost. [SOURCE: SOP V3 §XI]

Battery swap — procedure (LGA-style)

  1. On-site operator pings remote operator on Slack: “Battery at 25% — preparing swap.”
  2. Wait for remote operator acknowledgement before proceeding.
  3. Move the robot to a safe staging spot (not blocking walkways).
  4. Sit the robot.
  5. Power down (hold battery button).
  6. Remove top shell → swap battery → replace shell (4 screws, snug only).
  7. Double-click new battery to power on.
  8. Verify boot (cooling fan + green status LED on front face).
  9. Ping remote operator: “Swap complete, robot back online.”

Battery swap during a run is on-site responsibility. The on-site operator initiates and completes the swap with explicit remote acknowledgement. [SOURCE: ABM Operations Manual §"On-Site Oversight and Safety Intervention"]

Quality checks

  • Spare battery is on the charger whenever the primary is in the robot.
  • Metrics screen is checked at regular intervals in teleop (no auto-thresholds apply).
  • Battery never starts a mapping run below 100%.
  • Top shell screws are snug, not over-tightened.

Common failure modes

IssueLikely causeAction
Robot auto-sits unexpectedly during autonomous runHit 75°C motor temp or 20% battery thresholdVerify metrics. If thermal, wait for cooldown. If battery, swap.
Robot dies mid-mappingBattery not at 100% at startRestart mapping from scratch with full battery. [SOURCE: SOP V3 §XI]
Top shell cracked or threads strippedOver-tighteningReplace top shell. Report.
Spare battery only half-charged at swap timeSpare not staged when run beganAdjust deployment habit: stage spare at run-start, not run-mid.

Conflict resolution log

  • [RESOLVED 2026-05-18 — C1: Motor auto-sit = 75°C confirmed.] April 2026 GO2 ABM SOP lines 587, 604, 803.
  • [RESOLVED 2026-05-18 — C6: mislabeled duplicate of C1.] C6 was recorded as a “battery cutoff temperature” conflict but the underlying text refers to motor temperature, not battery. C6 collapses into C1 and is retired from the conflict ledger.
  • [RESOLVED 2026-05-18 for GO2 — C3: 75°C uniform across all modes.] April 2026 ABM SOP does not define a lower “delivery max” threshold; the 75°C motor threshold applies uniformly (lines 588, 604). The 68°C value from the older Robot Delivery SOP is either stale GO2 or applies to a different robot — see /robots/go2/operation/delivery/ for the robot-identity question.

Escalation

  • Persistent thermal events not explained by ambient conditions → engineering Slack with timestamps and motor-temp panel screenshots.
  • Battery hardware concerns (rapid drain, won’t hold charge, won’t power on after a single-tap charge check) → flag immediately; do not deploy with a suspect battery.

Source notes

  • [SOURCE: GO2_Standard_Operating_Procedure_V3.docx] — §V (Hardware Reference), §XI (Mapping — full-battery rule), §XV (Teleop — no auto cutoff), §XVI (Continuous Monitoring), §XVIII (Shutdown).
  • [SOURCE: GO2_Standard_Operating_Procedure_ABM.docx] (April 2026, Tyler Kugima) — confirms motor 75°C auto-sit, “operate well below 75°C”, cooldown “sit and let cool” without prescribed duration. Authoritative for ABM-LGA.
  • [SOURCE: GO2_General_Operating_Instructions_V3.docx] — older companion, source of C1/C6 conflict (now resolved).
  • [SOURCE: ABM Operations Manual.docx] — battery-swap remote-acknowledgement protocol.