Williams have finally joined in the 2013 fun and launched their car for the coming season, unveiling the FW35 in the Barcelona pit lane ahead of the second week of testing. The new car comes with a modesty panel to hide the stepped nose, and an unusual looking front, but is so far causing more controversy at the rear.

With a new exhaust design, Williams have opted to go the same way as Caterham in trying to direct the flow at the rear. The FIA aren't looking too kindly on this so we could see a design tweak in the near future.

Regardless, the car made its debut in the Barcelona paddock and was soon out on track for a shakedown in the hands of Pastor Maldonado.

I felt happy after the first run this morning and we then completed a busy day of testing. It was great to get out on track in the new car. There is still a lot to discover with the new car, but this is a good starting point for us for the season.

- Pastor Maldonado, Williams

Williams also broke some sponsorship news today, confirming an extension of their partnership with Randstadt and a brand new deal with Experian - good work in these tricky financial times.

The team claim their new car is 80% new bits and pieces, despite still being an evolution of the 2012 challenger. With the regulation stability, it's an impressive feat to have changed this much, and technical director Mike Coughlan explained what they are focusing on for the year ahead.

The Coanda effect is going to be a big thing for us. There’s been no rule clarification concerning this area of the car, so we’ll work closely with Renault to maximise the available gains. Use of the DRS is more restricted this year, so we’ll take some resource away from that and focus on other areas.

- Mike Coughlan, Technical Director, Williams

Williams F1 saw something of a resurgence in 2012, after a series of very disappointing seasons. With one surprise victory at the hands of Pastor Maldonado, and decent pace in qualifying on Saturdays, the team will be hoping for further progress in 2013.