Equation 3 · Part 5 · From Origins to Frontier: A History of Robotics and Embodied AI
subscript
subscript
What this part means
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
Its job in the formula
A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.
Full expression→subscript→Article meaning
The passage around this formula
The arithmetic behind that result is worth making explicit, because it explains why the next eighteen months mattered more than the raw distance suggests. If a course of length L miles must be driven without a mission-ending error, and a vehicle’s probability of such an error is q per mile and roughly independent from one mile to the next, the probability of finishing the course is approximately . Over a 142-mile course, even a per-mile reliability of 99 percent yields a finishing probability under 25 percent, and the 2004 fleet did not come close to that bar. This is illustrative arithmetic rather than a number drawn from any cited study, but it frames what changed by…
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
Open the illustrated subscripts: which member of a family? guide →
Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.