Remote Control (Remote Control Unit)
Handheld or wearable devices with stringer bars, buttons, or switches.
Operates on industrial-grade 2.4GHz frequencies (or other licensed bands for remote control).
There may be proportional control (for smooth grapple on/off) or on/off toggle.
Receiver unit
Mounted on a grab machine (e.g., crane grab, excavator grab).
Receives signals from the transmitter and relays commands to hydraulic/electric control valves.
It usually has a fail-safe mechanism (automatic stop if the signal is lost).
