Build a multi-camera hardware device

Vecna is looking for a hardware partner on its hemispheric imaging system research. The legacy design utilizes 17 cameras with a 640x480 (VGA) resolution that run at 30fps in 8b Bayer mode. This requires 156.7 MB/s transfer speeds. Max USB3 speeds allow for up to doubling this rate. By replacing the current VGA sensors with 1080p sensors and replacing the integrated Camera Cubes with discrete lenses, we seek to improve the quality both globally and locally. Using binning, we seek to run all sensors in VGA mode to replicate the current functionality. Turning off binning on up to 4 cameras should then enable clocking out a high-resolution region of interest. With 4 cameras running 1440x1080/30fps and the remaining 13 at 720x540/30fps, the required data rate is 338MB/s, which is at the upper end of USB3 bandwidth. Some units from the current design also suffer from inadequate overlap at the top of the hemispheric view. This is due to slight variation in placement of the camera modules. For this proposed revision, we seek an increased the field of view (FOV) to be used to ensure that the top sensor always has adequate overlap. This should also ensure the bottom ring of sensors also sees beyond the full 180 degree hemisphere. The challenges and risks of this update include: ● Size: The size of the unit will likely need to increase to accommodate a larger image sensor and discrete lens. ● Differential Signaling: The number of high speed lines will increase from 2 per camera to 4 as the signals go from single ended to fully differential. There are only a total of 10 differential clock inputs available in the FPGA. In order to accommodate 17 signals, we propose sharing one clock per 2 cameras. Skew between data lines can be calibrated during start up. Since a common clock drives all cameras, this should not be an issue. In order to reduce the risk of this solution, we propose a developing a simple prototype board to prove this concept works. In the event it does not work, the backup plan will be to use a Lattice MIPI bridge chip to merge datalanes. ● USB3 bandwidth varies from PC to PC. Sustaining 300MB/s and higher requires a high performance computer. DELIVERABLES Vecna is seeking two working prototypes with the following features: ● 17 image sensors with at least 1440x1080 resolution. Up to 4 of these sensors will stream at full resolution while the remaining 13 stream at 2x binned mode. ● USB3 for data transfer and power. ● Total size will be minimized based on size of the imager sensor and lens.