LengthLock

• ECB Recreational Cricket Safety Regulations (Dec 2025) say machines should be run only by experienced adults, never by U18s, and BOLA says short legs for under-12s and a playable speed per player → rev A2 NetKey pod: the DialDrive moves only after an adult coach card, each batter card sets a speed ceiling the SightCam checks every ball, a short-legs prompt for U11/U12, and a session record for the welfare officer
• Manuals say ball consistency drives accuracy and residue builds on the wheels after about a dozen leather balls → the loop closes on measured length, so it corrects drift whatever the cause, and flags the wheels when the correction keeps growing
• Dial numbers are not speeds (light balls come out faster; two machines differ by 5–10 mph) → the SightCam learns each machine's dial-to-speed map per ball type
• A radar gun gives speed only, at about ±1 mph → the CAD report shows a 2 km/h drift moves the bounce 150–210 mm while the camera resolves length to 9–31 mm, so the loop holds length, the thing the batter feels
• Modifying a machine that throws at people is a warranty and liability worry → the DialDrive straps on, is never wired into the machine, announces every move, respects a coach speed ceiling and goes limp on any fault
• Newer machines use membrane keys or tablets → rev A is honest that the DialDrive fits rotary knobs only; other machines get SightCam advice, and a maker partnership is the route to the loop

Coach / feederBatterAcademy owner

1. 01Trigger: the coach sets good length (6 m), off stump, 110 km/h and swaps in a new set of balls
2. 02Detection: the SightCam fits each ball's arc and finds the last 3 bounces 0.4 m short of target
3. 03Action: the DialDrive beeps twice, lights amber and turns the speed knob 3.8 degrees between balls
4. 04Outcome check: the next balls land on the 6 m band; the log shows 31 of 36 balls in the band and a wheel-health trend for the owner

Outcome: A full session at the length the batter needed, without the coach chasing the dial (est.)