R格子包，auto.key边框的边距

Question

图例周围的边框（auto.key）底部太紧了。如何增加它？

library(lattice)
    arr<- array(replicate(10, rnorm(10)), dim =c(10,10,10) )
dotplot(arr, type = "b", horizontal = F, col = techColor
        , main =list( " Centrality", cex=1.5), xlab.top="",as.table=T,
        ylab =list( "Centralities", cex=1.3), 
        xlab = list("Proportion Cutpoints"), 
        scale=list(y=list(cex=1.2,  alternating =1), cex =1),
        auto.key=list(  points = F, border= "grey",
                          space = "top", lines = T, columns=4,height=10,
                          title = "Technologies"),
        par.settings = list(superpose.line = list(col = techColor, lwd=2, lty=1:6 ),
                            layout.heights= list(xlab.key.padding = 1), 
                            layout.widths = list(key.ylab.padding = 1)),
        par.strip.text = list(cex=1.5))