Community volunteers have been helping officers in the Darley Dale area to monitor speeding traffic.
The Community Speed Watch scheme has been launched to help address residents concerns about speeding.
Volunteers received training on how to use the detection equipment and now spent around five hours checking the traffic in four different sessions on Eversleigh Rise (B5057) at South Darley.
Fourty-one motorists were found to be travelling above the 30mph speed limit.
They will now receive a letter to inform them about the check and that if they continue to speed they risk a fine and penalty points on their driving licence.
PCSO Granville Nixon of the Darley Dale Area Safer Neighbourhood Policing Team said: “After receiving complaints from local residents, a number of people said they would be happy to volunteer for Community Speedwatch and help target the issue.
“The initiative is all about reminding and encouraging drivers to have respect for the wider community and to keep within legal speed limits. We will be continuing to carry out checks at various times and days over the coming months.”