They resemble the Battle Jackets.
In Age 761 a RR Mech Soldier called the Rampaging Robot was rampaging in Spinach Wastes. It was noticed by Android 8, who informed Goku about it upon meeting him. Goku dealt with the Rampaging Robot as per Eighter's request.
A distinct RR Mech Soldier called the Rampaging Robot appears as an early enemy in Dragon Ball Z: Kakarot.