Bumpers zifite imirimo yo kurinda umutekano, gushushanya ikinyabiziga, no kunoza ikirere kiranga ikinyabiziga. Duhereye ku mutekano, iyo habaye impanuka yo kugongana byihuse, imodoka irashobora kugira uruhare runini mu kurinda imibiri yimbere ninyuma; irashobora kugira uruhare runini mukurinda abanyamaguru mugihe habaye impanuka nabanyamaguru. Kubireba isura, irashushanya kandi yabaye igice cyingenzi cyo gushushanya isura yimodoka; icyarimwe, bumper yimodoka nayo igira ingaruka runaka yindege.
Muri icyo gihe, mu rwego rwo kugabanya imvune ku bari mu modoka mu gihe habaye impanuka yo ku mpande, ubusanzwe hashyirwaho icyuma cy’umuryango ku modoka kugira ngo imbaraga zirwanya impanuka z’umuryango w’imodoka. Ubu buryo ni ngirakamaro, bworoshye, kandi bufite impinduka nke kumiterere yumubiri, kandi bwakoreshejwe cyane. Kwishyiriraho urugi rwumuryango nugushira ibiti byinshi byimbaraga zikomeye murwego rutambitse cyangwa muburyo butagaragara mumuryango wumuryango wa buri rugi, rukaba rufite uruhare rwimbere yimbere ninyuma yimodoka, kuburyo imodoka yose ifite bumpers "kurinda". imbere, inyuma, ibumoso, n'iburyo bw'imodoka. , gukora "urukuta rw'umuringa", ku buryo abari mu modoka bafite ahantu h'umutekano ntarengwa. Birumvikana ko gushiraho ubu bwoko bwa bumper yumuryango nta gushidikanya ko bizongera ibiciro kubakora imodoka, ariko kubatwaye imodoka, umutekano numutekano biziyongera cyane.