m$machine <- ifelse(m$level!=0, "on", 0)

tlag <- 2
# check to see if timeout period has elapsed
for (i in seq_along(m$machine)){
    if(m$machine[i]!="on") {
        nback <- i - tout
        if (nback <=0 ) nback <- 1
        if (sum(m$level[nback:i]) == 0){ #light should be off
            m$machine[i] <- "off"
        }
    }
}

for (i in seq_along(m$machine)){
    if(m$machine[i]==0) m$machine[i] <- "on"
}