You may need to combine different materials to get all the qualities you're looking for. Here are some ideas:
Canvas and denim are strong, abrasion-resistant fabrics. Another option is ripstop nylon, which is manufactured to be strong, lightweight, and resist rips and tears. The weight of your fabric will determine how strong it is. For additional strength, make sure to reinforce your seams (and again at stress points).
For protection from sharp edges, consider a quilted lining, or leather (pleather, vinyl) sewn in corners or other stress points.
You can waterproof canvas-like fabrics by waxing, or buy already waxed canvas. You can also buy commercial waterproofing spray, typically sold in outdoor stores. Even with waterproof fabrics, you'll need to seal the seams after sewing to make sure it is fully waterproof.
- Other waterproof fabrics include oilcloth and laminated cotton, but these are probably not sturdy enough on their own to carry a heavy device. Instead, you could consider sewing an inner case out of the sturdy fabric, and an outer waterproof case out of the oilcloth.
- You could consider vinyl / PVC for this as well (personally, I think it'd be difficult to get a good seal on the corners, but I've never sewn with it)
- Ripstop nylon is generally at least water-resistant; check the particular brand to be sure and spray where necessary
All of these materials are sewable on your standard machine!
- Make sure to use a sharp, appropriately sized needle, and don't sew too fast
- Denim and canvas will be fine as long as you don't sew too many layers at once
- Same for garment-weight leather (although small bits would be easy enough to do by hand if you're worried)
- Oilcloth, laminated cotton, and nylon tend to "stick", so it's recommended to use a teflon foot. You can also place a piece of tissue paper underneath the fabric if it is sticking to the feed dogs.
After researching these options, I would probably try ripstop nylon, leather-like corner reinforcements, and waterproofing spray. Camping forums ("make your own gear") are good sources of info and product recommendations for ripstop nylon, as it is often used in camping gear and hammocks.