SHOOTING ON THE MOVE: HOW MUCH AIM A ROBOT LOSES BY IGNORING ITS OWN VELOCITY, AND WHETHER A VIRTUAL-TARGET CORRECTION RECOVERS IT

Abstract

A robot that launches a projectile while driving inherits its own velocity, so a firing solution computed for a stationary machine misses. Competitive robotics teams handle this with a virtual-target correction, aiming at a shifted point rather than at the goal, but the size of the error being corrected, and whether the correction survives aerodynamic drag, are rarely quantified. This study builds a point-mass trajectory model of a FIRST Tech Challenge DECODE launcher with quadratic drag and evaluates it over the competition's own launch zones, 0.86 to 3.90 metres, using a real robot's measured flywheel calibration, hood range and top speed. Three results follow. First, drag alone is not a detail: a firing solution computed without it falls short by 0.27 metres at 1.75 metres and by 0.85 metres at 3.90 metres, that is 15 to 22 per cent of the range. Second, ignoring the robot's own motion costs roughly half a metre of range per metre per second of robot speed, reaching 1.48 metres at the machine's top speed of 2.73 metres per second, which is more than twice the width of the goal opening. Third, the virtual-target correction works: aiming at a point 0.5 to 1.5 metres nearer than the goal brings the residual error to within four millimetres at every range where a solution exists. The correction has one boundary, and it is geometric rather than aerodynamic: with a turret 0.30 metres above the floor and a hood limited to 60 degrees, targets closer than about 1.5 metres cannot be entered from above at all, moving or stationary, and raising the turret to 0.60 metres removes the restriction. The practical ranking for a team is therefore drag first, own velocity second, and flywheel-speed error a distant third, since a 5 per cent speed error costs 0.22 to 0.36 metres, less than driving at one metre per second and ignoring it.

Keywords: projectile motion, aerodynamic drag, robotics, FIRST Tech Challenge, trajectory simulation, shooting on the move

References

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How to cite

Iliyas A. SHOOTING ON THE MOVE: HOW MUCH AIM A ROBOT LOSES BY IGNORING ITS OWN VELOCITY, AND WHETHER A VIRTUAL-TARGET CORRECTION RECOVERS IT // Central Asian Scientific Journal. – 2026. – No. 4(32), Vol. 1. – Pp. 223–228.