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  <xs:element id="coch_ScheduleOfFairValueMeasurementsOfTheForwardPurchaseAgreementWarrantLiabilityAbstract" name="ScheduleOfFairValueMeasurementsOfTheForwardPurchaseAgreementWarrantLiabilityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="coch_EstimatedCostOfWarrantLiabilityPerUnit" name="EstimatedCostOfWarrantLiabilityPerUnit" type="dtr:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xs:element id="coch_AverageBatteryLife" name="AverageBatteryLife" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="coch_AnnualIncreaseInProductPriceDueToInflation" name="AnnualIncreaseInProductPriceDueToInflation" type="dtr:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="coch_October2025InvestorWarrantsMember" name="October2025InvestorWarrantsMember" type="dtr:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="coch_ScheduleOfPropertyAndEquipmentNetAbstract" name="ScheduleOfPropertyAndEquipmentNetAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="coch_ScheduleOfLiabilitiesMeasuredAtFairValueOnARecurringBasisAbstract" name="ScheduleOfLiabilitiesMeasuredAtFairValueOnARecurringBasisAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="coch_FairValueMeasurementsScheduleofLiabilitiesMeasuredatFairValueonaRecurringBasisDetailsTable" name="FairValueMeasurementsScheduleofLiabilitiesMeasuredatFairValueonaRecurringBasisDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="coch_FairValueMeasurementsDetailsTable" name="FairValueMeasurementsDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
</xs:schema>
