I found this nice summarizing PDF, so this blog post is simply about hardware.
You can disregard the "(c) 2007" at the bottom; it sure is Rheinmetall copyright, but the presentation was surely written later than in 2007.
The presentation file shows that - including designs taken from subsidiaries - Rheinmetall covers a wide range of innovative hand grenade designs:
- flash bangs
- offensive hand grenade
- mini offensive hand grenade
- defensive hand grenade (preformed fragments)
- smoke hand grenade
- flash bangs with screw-on module for extra effect
- airburst hand grenade
- enhanced blast (thermobaric) hand grenade
- stackable blast hand grenade
- shaped charge hole cutter hand grenade
- multispectral smoke hand grenade
not in portfolio, but under development elsewhere:
not in portfolio, but existing:
- modular hand / rifle grenade (such as the old Polyvalent MDF)
- modular defensive/offensive hand grenade with separate preformed fragments (such as competitor's Diehl DM 51 that's the Bundeswehr's standard hand grenade)
not in portfolio, may not exist anywhere:
- linear cutting charge formed with stackable hand grenades
- mini enhanced blast (thermobaric) hand grenade
This shows how diverse and complicated in design a munition of war with roots in the 11th century has become. The development is ongoing.
It may very well be that the air burst hand grenade** and the blast enhanced hand grenade*** will be introduced into the Bundeswehr in the future, departing from the traditional offensive and defensive (or hybrid as DM 51) pattern. The stackable type looks like a military engineer munition. I sure hope there will be plenty of those multispectral (red phosphorous) smoke hand grenades in stocks.
*: when set to defensive it explodes with fragmentation effect, when set to offensive (blast-frag) hand grenade mode it likely first sheds its frag shell with low energy, then explodes as offensive (blast) hand grenade.
**: which directs its fragments such that safe distances not much greater than with offensive hand grenades can be achieved
***: It would likely not called "blast enhanced" if introduced in the Bundeswehr, for NGOs caught up with this being a code for "thermobaric".