My Projects

Cone icon by Fornax, CC-BY-SA 3.0, wikimedia commons 1)

Published 28 Mar 2023


This radio controller toy from Maisto looks like a great candidate for converting into a Mars explorer type cross country, autonomous, robot. I think it is functional, but without a battery or remote control. From the circuit board it appears to have been made about 18/11/2014.

Rock Crawler XL overview
Cross country radio controlled Rock Crawler XL




Hardware description

The Rock Crawler has three electric motors, two of them drive the front and rear axles, the third drives the front wheel steering. Each wheel has independent suspension allowing it to negotiate relatively large obstacles. The wheels have large, soft, tyres which should give good traction. The system is designed for a 6.4V battery, and is normally controlled by a 2.4GHz remote control.

The front and rear motors are driven together, so it is in continuous 4 wheel drive mode. The steering is driven by a separate motor which has a potentiometer feedback so you can determine the direction of the front wheels.

The electronics consists of a single board with five ICs and a 12.000MHz crystal. U1 0330 (3 pin 3V LDO regulator?), U2 TA6586, (8 pin, bi-directional DC motor driver), U3 TA3567 1628 (8 pin), U4 AAIAT (5 pin), U5 RX97A-2 (16 pin).

Tear down

Body removed, top view

Body removed, side view

Cover removed

Circuit board top Circuit board bottom

References and Additional Resources

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