There have been many field trials with a moving robot,
http://spectrum.ieee.org/automaton/robotics/industrial-robots/bosch-deepfield-robotics-weed-control
10mm round bar hitting weed into ground has been found effective.
Stupid enough they started with a bladed like tool. Why bash breaks more of the plants cells so large infection area for items in soil to infect plant and make it critical sick. Yes using a meat hammer on weed plants is surprising effective other than the soil compaction issue.
Issue with chop is clean cut areas plant can heal off better.
Basically you don’t want a sharp knife edge. You want something nice and dull to do the worst cutting job possible. I use bash because you are after either pure bash like boschs tool or you want something fairly blunt. Knife edge is basically totally wrong as it cuts way too cleanly. To put it in prospective wood cutting tools you are after a block splitter blade or back not a cutting axe.
bagginsdada 2-10mm totally blunt is known to work as long as weed is driven deep enough. There is a reason for 3cm in so you bring the broken bits of plant into contact with the higher area of bacteria and other things to make it life miserable and hopefully kill it in case happens to be some resistant plant to being broken up.
Do note the bosch machine does not mess around 1.75 weeds per second bashing rate. One thing about bash if it like a solenoid it can retract through a cleaning plate, Lot more resistant go being blocked up due to soil type.
Yes Palomineo you understood exactly what I meant by bash. Chop/knife is less effective than bash against weeds by all field trials. Its funny the things that turn out to be effective.
Even when cutting weeds tops off a blunt tool does a better job than a nicely sharp tool. You use nice sharp tools when cutting plants you want you use blunt horible tools when handling the plants you don’t want. Its all about how well will this cause infection. Yes you clean tools when cutting plants you want and you don’t clean weeding tools that much because you are hoping to introduce infection. If you have weed tea dipping your weeding tools in that also helps kill rate. Nice coating of organisms plant does not want. Bash/cutting weeds is not just about running them out of steam its also about attempting to allow infection to attack them.