Former world champions Williams hope their new FW38 Formula One car, presented online on Friday, will address last year's problems and be quicker on the slower tracks and in wet conditions.
"The FW37 was a pretty effective car and so we concentrated on understanding the areas where we could improve it without losing the attributes which made it effective," said engineering head Pat Symonds in an interview conducted by the team.
"It is no secret that the low speed performance of the FW37 didn’t match its high-speed performance so a lot of time was spent looking into why this was and subsequently making changes, which we hope will improve the situation."
Williams finished third overall last year in the constructors' championship for the second season in a row but again failed to win a race.
The British-based team, whose last world championship title was with Canadian Jacques Villeneuve in 1997, have not won a grand prix since Venezuelan Pastor Maldonado triumphed in Spain in 2012.
The new season starts in Australia on March 20
With Brazilian veteran Felipe Massa and Finland's Valtteri Bottas, Williams took four podium finishes in 2015.
Team founder and principal Frank Williams said retaining third place would be a challenge but the aim was to return to the ranks of race winners in a series dominated by engine partners Mercedes for the past two years.
"We will have to wait until Melbourne to find out exactly where we stand in the pecking order but I’m confident that our hard work over the winter will stand us in good stead," said Williams.
"As a team we need to be able to win races, which is what we are always trying to do," said Bottas, now in his fourth season with the team and linked to Ferrari last year as a possible replacement for compatriot Kimi Raikkonen.
"I’m sure we have made improvements everywhere as a team, so we’re definitely looking to fight for better results this year."
Deputy principal Claire Williams said the team had started design work earlier than usual and the car launched on Friday would have further updates before racing in Melbourne. It will make its track debut at Barcelona's Circuit de Catalunya on Monday at the start of pre-season testing.