You have been assigned to write filters to reduce noise in the data coming from a LIDAR sensor attached to your robot. The LIDAR generates scans at a certain rate. Each scan is an array of length N of lloat values representing distance measurements. Nis typically in a range of ~[2Dl]. 1000] measurements, and it is fixed. Measured distances are typically in a range of [0.03, 5D] meters. Each time a scan is received. it will be passed on to the filters. Each filter object should have an update method, that takes a length-N array of ranges and retums a filtered length-N array ot ranges.

We want you to write two different filter objects: a A range filter

The range filter crops all the values that are below range_min (resp. above range_max), and replaces them with the range_min value (resp. range_max)

. A temporal median filter The temporal median filter returns the median of the current and the previous D scans: }' Em =median(x.(r), 116— 1), . xfcx — DJ) where x and y are input and output length—N scans and i ranges from D to N—1. The number of previous scans D is a parameter that should be given when creating a new temporal median filter. Note that, although the update method will receive a single scan, the retumed arrayr depends on the values of previous scans. Note also that the for the first D scans, the filter is expected to return the median of all the scans so far.