Problems with sleep and our body’s internal clock can influence mood and trigger relapses in bipolar disorder. Traditional ways of measuring this are complicated and only capture short snapshots of time. In Ambient-BD, we are testing radar sensors that quickly track sleep and circadian timing at home over 3 months. By comparing these to gold-standard methods, we aim to better understand how daily rhythms affect mood and wellbeing to find better ways of supporting people with bipolar disorder.