I always end up having a 'USB device not recognised' error while I fix my external harddisk to my laptop. Even a slight disturbance causes this error due to the weight of the disk, and I find it really difficult to move around with my laptop fixed to the hard disk.
I was thinking of making an enclosure which could be 3D printed and fixed as a cap to the USB port of the hard-disk so that it could then be clamped onto the laptop. However, for clamping onto the laptop's flat surface there should be a mechanism that makes it sturdy, so that there is no movement of the USB which leads to the connection error.
The enclosure should also be able to be firm when the cable is yanked in any direction.