用ns2模拟aodv运行otcl的时候总是出现这样的问题

(o13 cmd line 1)
invoked from within
"o13 cmd random-motion 0"
invoked from within
"catch "$self cmd $args" ret"
invoked from within
"if [catch "$self cmd $args" ret] {
set cls [$self info class]
global errorInfo
set savedInfo $errorInfo
error "error when calling class $cls: $args" $..."
(procedure "o13" line 2)
(SplitObject unknown line 2)
invoked from within
"$node($i) random-motion 0"
("for" body line 3)
invoked from within
"for {set i 0} {$i <$val(nn) } {incr i} {
set node($i) [$ns node]
$node_($i) random-motion 0
}"
(file "aodv_0.tcl" line 46)